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Apple Cluster Controller 

and Appleline 

Sales Reference Guide 


The following people at Apple Computer were principal contributors to this guide: 

Jim Armstrong, Ferhan Cook, Dennis Demos, Barney Dewey, Bruce Friesen, Arnie 
Lapinig, Jane Silverstein, and Dave Sus arret. 

Some of the information contained in this guide is from communications hardware and 
software manufacturers liturature and industry trade publications, and therefore subject to 
updating. This Guide is informational in content and products mentioned do not constitute 
endorsement by Apple Computer, Inc. Apple Computer cannot be responsible for 
changes in information given here regarding pricing, rates, availability or suitability of 
products for any purpose. If you find incorrect information in this guide, please let us 
know, and we will attempt to include them in future updates. 

Notice of copyrights, trademarks, service marks, and registrations: 

Apple, Apple n, //e, Access //, Access ///, Access 3270, Lisa, Lisa Terminal, Macintosh, 
and MacTerminal are registered trademarks of Apple Computer, Inc. 

IBM is a trademark of International Business Machines Corporation 

This guide was prepared on an Apple /// with /// E-Z Pieces and a Macintosh with 
Mac Write, and typeset with an Apple Lisa and a CompuGraphic MCS 8400 
phototypesetter and a new printing product. 

Table of Contents 

Selling and Reference Guide for: 
Synchronous Communications Products 

Introduction Pagei 

Chapter 1 Communications Market Overview Page 2 

The 3 Worlds of Communications - Figure 1 

Chapter 2 Introduction to Data Communications Page 6 

The IBM Big Picture - Figure 2 

A Brief Introduction to the IBM 3270 World 

Protocols and Protocol Converters 

Customer Requirements 

Apple Personal Computers as Terminals 

Terminal Types 

Chapter 3 Apple Synchronous Products Overview Page 15 

Apple Solutions - Figure 3 

Apple Cluster Controllers 

Chapter 4 Qualifying the Prospect Page 18 

Selling Appleline and Apple Cluster Controller 

Chapter 5 How to Demonstrate the Products Page 28 

Chapter 6 Communications Software Products Page 



Chapter 7 Competitive Product Listing Page 48 

Chapter 8 Appendices Page 51 

Figures 5-10 
Reading List 
IBM by the Numbers 



Purpose of the Sales and Reference 
Guide on Synchronous Communications 

The purpose of this selling guide is to quickly familiarize an Apple Authorized Dealer or 
Salesperson with the Appleline and Apple Cluster Controller products. This guide will also explain 
the concepts of terminal emulation and protocol conversion. Furthermore it will serve as a useful 
reference source and provide background material for seminars and demonstrations. 

A glossary of data communications terminology is provided at the back of this guide. If data 
communications terms are unfamiliar to you, you may want to look at the glossary before you read 
the rest of this guide. 

The Organization of this Guide: 

covers synchronous and asynchronous communications worlds. 

is an introduction to data communications and an overview 
of customers needs. 

tells how Apple products meet customers needs. 

covers sales scenarios qualifying the prospect. 

covers the demonstration of Apple synchronous 
communications products. 

lists compatible and competitive software products. 

lists competitive hardware products. 

is a Glossary, a Guide to IBM Numbers, a Reading List and Figures 5-10. 


Chapter 1 


The 3 Worlds of Communications 

One could say that there are three independent, yet interrelated worlds of data communications. The 
American Telephone and Telegraph world is by far the biggest with yearly revenues of over $165 billion 
dollars. This world comprises the highways and by-ways of voice and data communications. Wherever there 
is a communications wire between two points, chances are that AT&T owns it. 

The next biggest world is IBM. With yearly revenues of over $40 billion dollars, and about a 65% share of 
the mainframe computer market, it is nearly as big as everyone else in the computer business put together. 

IBM's communications are primarily EBCDIC character based and synchronously transmitted, with either a 
bisync or SDLC protocol. 

When standards regarding communications are set, generally they are patterned after either AT&T or IBM. 

The third communications world is everyone else in the business of moving information electronically. This 
world is primarily ASCII character based and asynchronously transmitted. This world has its origins in 
equipment that has evolved since the 1800's - well before the first electronic computer. 

The Micro-to-Mainframe Marketplace 

The exciting and demanding new micro-to-mainframe marketplace for communications products is just now 
starting to explode. In the early days of computers, the market was primarily technology driven. But the 
micro-to-mainframe market is primarily customer driven. Early users of personal computers in major 
corporations have helped generate a pent-up demand for methods to access existing data stored in their 
companies' mainframe computers. As the number of installed personal computers in large businesses doubles 
and quadruples, so too will the products that connect them to the corporate mainframe computers. International 
Resource Development has projected the size of this market and it is graphed in Figure 2. 

The Objective of this Guide: 

The objective of this selling guide is to explain the IBM communications world and to tell how Apples' 
synchronous communications products enable Apple personal computers to fit into that world. First we will give 
an introduction to the 3270 communications environment, then we will tell who the customers are that will be 
buying these products and for what reasons, and then we will explain how Apple products meet these needs. 


The 3 Worlds of Communications 

AT& T - Analog Voice Circuits/ Digital / X.25 
IBM - EBCDIC / Synchronous / SNA / SDLC 
Everyone Else - ASCII /Asynchronous 

Figure 1 

Growth of the Micro to Mainframe 










Total Installed Base: $7.97 billion 
at a 43% average growth rate 


Micro to Mainframe Communications Products 
Hardware and Software sales for the next 5 years 

Source: International Resource Development, Inc 

Figure 2 






HOST CPU (370, 303X 

, 308X) 


IBM Cluster Controller 

3278 3279 3178 3179 









81 XX 

System 3X 












The IBM Big Picture 

Figure 3 


Chapter 2 


A Brief Introduction To The IBM 3270 World 

In order to express the significant benefits offered by Appleline and Apple Cluster Controller to the potential 
corporate customer, it is necessary to understand the nature of that customer's environment. This brief 
introduction to that environment is intended to provide that understanding. For those who desire additional 
depth, a glossary of IBM software and hardware terminology and a guide to IBM product numbering is 
provided in Chapter 8. 

The great majority of large corporations today use large-scale IBM or IBM plug-compatible mainframes as the 
central computer in their data processing systems. Typically, hundreds or even thousands of CRT terminals and 
printers are in use on these systems. If all of these had to be handled directly by the mainframe little capacity 
would remain for actual computing. IBM had therefore chosen to distribute this terminal-handling burden to 
intelligent control devices (called, simply enough, controllers). Thus, a mainframe rarely communicates directly 
with a user's terminal or printers, but instead does so through a number of controllers arranged in some form 
of communications network. 

The most widely used communications network type utilizes an interrelated group of controllers, terminals, 
printers, and miscellaneous devices called, collectively, the 3270 or 327X family. When an IBM mainframe 
system is installed or expanded, members of this family are arranged building-block style into a 3270 
Communications Network. Many such configurations are possible, and a fairly representative one is 
diagrammed on Figure 3 . You may wish to refer to this diagram as the individual components are briefly 
described below. 

The heart of any computer system is, of course, the central or host computer. IBM has divided its various 
models of computers into families (also called series). The main memory size and processing power of 
different machines within a family may vary widely. Significantly, software written for one machine in a 
family can run with little or no modification on any other machine in the family. This feature makes upgrading 
of computer systems within a family much more simple and cost effective. It is this concept that catapulted 
IBM into its prominent market position in the mid-60's. 

In an IBM 3270 Terminal Network, the host is a member of the IBM 370, 303X, 308X, or 43XX family. 
(Note that the X's represent actual digits in model numbers of family members. For instance, the 43XX family 
includes, among others, 4331 and 4341 models.) 

As mentioned earlier, the host communicates with terminals and printers through a network of controllers. The 
type and arrangement of the controllers vary according to whether the controllers are handling local or remote 
terminals and printers. Thus, there exist two classes of terminal controllers - local and remote. 

Local controllers attach directly to a mainframe channel (a channel is roughly analogous to a connector into the 
system bus on a microcomputer). They are, therefore, often referred to as channel attached controllers. 


Remote controllers, as the name implies, are located anywhere from a few miles to several thousand miles 
away from the host computer site. Remote terminal controllers are not managed directly by the host, but are 
instead supported by an IBM Communications Controller (sometimes called a "front-end processor" or simply a 
"front-end"). It is typically a model 3705, though a newer version called the 3725 is starting to appear. Like 
a local terminal controller, a Communications Controller is channel-attached directly into the host. Remote 
terminal controllers communicate with the 3705 or 3725 via modems and communications lines (such as 
standard dial-up phone lines or dedicated transmission lines). A single 3705 or 3725 can be configured to 
support up to 32 remote terminal controllers in this way. 

Local controllers in a 3270 network are typically model 3274's. Remote controllers are typically either 3274's 
or 3276 's. You should note that a local 3274 and a remote 3274 are slightly different models and are not 
interchangeable. Either one, however, can be configured to support up to 32 peripheral devices (i.e., terminals 
and printers). On the other hand, a 3276 can only support up to eight peripheral devices. The Apple Cluster 
Controller emulates an IBM 3274/76 to the IBM host, but can have either 3 or 7 ports. A 3276 does have a 
CRT terminal built into it, while a 3274 does not. 

Each terminal controller (also called a cluster controller) acts as a communications hub for the peripheral 
devices clustered in its vicinity. Each peripheral device is connected to the cluster controller with a coaxial 
cable (similar to that used in cable television connections, and often called just "coax") which may be up to 
5,000 feet long. The attached peripheral devices are most often terminals or printers, but various other 
input/output devices such as card readers and bar code readers are also supported. 

A number of different models of IBM printers are used with 3274 and 3276 cluster controllers. The 3287, 
3288, and 3289 are fairly common models. 

The 3270 series CRT terminals, called terminal workstations in the IBM world, are available in both 
monochrome (model 3278) and color (model 3279) versions. Screen size options are available for both models. 
These options are (columns x rows): mod 1 (80x12 or 40x24), mod 2 (80x24), mod 3 (80x32), mod 4 (80x43), 
and mod 5 (132x27). The mod 1, mod 4, and mod 5 options are only available for the 3278. The 3278 and 
3279 are each also available in either full-graphics or character-only versions. This is indicated with a suffix as 
follows: B or G suffix = full graphics, A or no suffix = character only. 

As an example, the most common terminal workstation, the 3278 mod 2 (or mod 2A), is a monochrome, 
80x24, character-only terminal. This is often represented simply as a model 3278-2 or 3278-2A. The color 
equivalent of this, which is fairly common, is the 3279-2 (or 3279-2A). The less common 3279-2G 
(or 3279-2B) is a color, 80x24, full-graphics terminal. 

The 3278 and 3279 terminal workstations are "dumb" terminals; that is, they have no stand-alone computing 
capabilities. Replacing them with an "intelligent" terminal which has full stand-alone computing capabilities is 
very attractive to IBM 3270 Network users. 

You will sometimes encounter an older class of 3270 devices which are represented by the 3271 and 3272 
cluster controllers and 3277 terminals. These are now not nearly as common as the newer 3274 and 3276 
cluster controllers and 3278 and 3279 terminals. 


You should note that a 3274 controller can support both newer 3278/3279 terminals and older 3277 terminals. 
(3276 controllers do not support 3277's) The 3274 accomplishes this through the use of terminal adapters; 
Type A adapters work with 3278's and 3279's and Type B adapters work with 3277's. 

You will often hear the terms BSC and SNA/SDLC applied to a 3270 environment. These are software 
protocols, one or the other being used for the transmission of data through a given 3270 Network. BSC, 
which stands for Binary Synchronous Communications (often called bi-synch), is an older protocol, but remains 
popular. SNA/SDLC, which stands for System Network Architecture/Synchronous Data Link Control 
often called just SNA or SDLC), is more powerful, but also much more expensive. These protocols differ 
substantially at points in the network. However, the protocol used between a cluster controller and a 3278 or 
3279 terminal is essentially the same in the BSC and SNA/SDLC environments. 

Protocols and Protocol Converters 

Protocols are established rules governing communications. Whenever two pieces of equipment are connected 
together, certain rules must be preset in order for communications to take place. Transmission speed, how to 
verify connection, the organization of one's and zero's to identify characters, which characters are control 
characters, and which are data, and so forth, are just a few of these rules. 

Therefore, a protocol provides a method for the orderly and efficient exchange of data by establishing rules for 
the proper interpretation of controls. 

ASCII asynchronous communications are one type of protocol and EBCDIC synchronous BSC and SNA/SDLC 
are other types of protocols. 

Some of the key tasks of a communications protocol are: 

• Specify the Code Set - i.e. ASCII or EBCDIC 

• Specify Data Format - Asynchronous or Synchronous - Full or Half Duplex 

• Initiate and Verify a Communications Connection 

• Identify Persons or Equipment on Each End 

• Establish Order of Transmission and Precedence 

• Handle Error Situations and Re-transmissions 

The purpose of a protocol converter is to change from one protocol to another. From ASCII to EBCDIC, from 
Asynchronous to Synchronous, and from the control functions of environment to that of another. 

It is hoped that this discussion has provided you with sufficient background to enhance your Appleline and 
Apple Cluster Controller sales efforts with the IBM 3270 user. For more detailed information you can refer to 
the information given in Chapter 8. 



^ Start 1 2 3 4 5 6 7 8 Stop 
0 Space I I I I Tl J"T 

ASCII - Character Code for "A" 

1 2 3 4 5 6 7 8 

1 Mark r— i r— i r— i 

0 Space I LJ I I |_ 

««- EBCDIC - Character Code for "A" 

Start Character Stop Start Character Stop Start Character Stop 

n^-l I Tl«-l l Tl 

Asynchronous Transmission 

Sync Sync SOH Header STX Data ETB BCC BCC Sync Sync SOH Header 
I I I I I I I I I I 

Bisynchronous Transmission 

Begin Frame End Begin Frame 

Flag Address Control Information Check Flag Flag Address Control Information Check 

8 Bits 8 Bits 8 Bits Multiple of 8 Bits 16 Bits 8 Bits 

Synchronous Data Link Control (SDLC) Transmission 


Customers' Requirements: 

The integration of microcomputers, either as personal computers or as intelligent workstations, into the data 
processing environment of major organizations-corporate, governmental, and institutional-became a key issue 
of the data processing industry during 1983. The question is not whether microcomputers should be integrated 
into mainframe environments, but rather how this integration can best be accomplished for the most efficient 
utilization of an organization's computing resources. 

The first generation of personal computers communicated through very slow 300 

bit-per-second modems and were used primarily to link to the new information utilities. After 1980, however, 
as VisiCalc revolutionized the corporate professional's working methods, a major change began to occur. A 
demand for access to corporate information stored in mainframe data bases began to grow. It was led by 
managers and professionals who found that re-entering data from printed spreadsheets wasted time and effort 
when the same data was already stored in digital form on the corporate mainframe. During the past two years, 
the demand for access to mainframes through micros has reached a crescendo. 

In making an attempt to replace DEC and IBM terminals with microcomputers, it is important to understand the 
different types of users and what their needs are. Following is a brief profile of the various terminal users and 
how we best answer their needs. 

The 4 Types of Users: 

1 . Casual - The casual user is usually a professional, who has minimal requirements for accessing the 
mainframe. He/She may query a database once or twice a day, he/she may use an electronic mail system, and 
check the prices of securities. Even though the requirements are small it is important to have this capability at 
his/her fingertips. These users are perfect candidates for the kind of capabilities Apple offers in the area of 
data communications. They usually do not want a lot of equipment on their desk; therefore, the concept of the 
integrated workstation is very attractive. 

2. Clerical - POWER ENTRY! This user probably spends about 7 1/2 out of 8 hours in a day at his/her 
terminal inputting data. Therefore the user is always in terminal mode. He/she may input inventory 
information, purchase order information, or some other type of major database information. More often than 
not this user is trained on a particular terminal type. It is possible to go after this type of terminal replacement. 
However, considering the differences between the Apple computer in terminal mode and the 3278, you may 
find resistance to change. Keep posted on future characteristics added to the software and hardware that give 
us the characteristics we emulate. Also, if this user is always in terminal mode and has no use for the rest of 
the functionality of the personal computer it makes it a tougher sell. Not impossible but not our perfect target. 

3. Professional - Not dissimilar to the casual user above, the professional has some requirements for 
terminal mode. He/she may access a corporate database a few times a day, may have access to a securities 
database, and perhaps use electronic mail. The professional probably has a greater requirement for things like 
spreadsheets, personal databases, minimal wordprocessing, and Mac or Lisa drawing packages. As with the 
casual user, the professional often wants the ability to tie into a mainframe but wants one integrated workstation 
that is easy to use instead of a cumbersome, complicated terminal in addition to his/her personal computer. 
Often, the professional requests the ability to leverage off of the information contained in the database by 
copying it and pasting it into a spreadsheet. This ability saves the user from having to copy the data on paper 


when he/she is terminal mode and then re-keying the data into the spreadsheet. This powerful integration 
provides all the processing power right on the desktop. The professional is an ideal candidate for the sale of 
Mac's and Lisa's, which integrate the personal computing functions required by the individual and the terminal 
software with Appleline or Apple Cluster Controller to give him/her access to the mainframe. 

4. Programmers - IBM environment programmers are usually used to the functionality of the 3278 with all 
of its special keys and attributes. If they have spent a long time on this kind of terminal, they may be quite 
resistant to the changes when using a personal computer for this function. There are a few considerations here. 
First, are they used to a true terminal and are they resistant to learning variations? Second, do they have a 
need for the other applications on a personal computer? There are various levels of programmers. Some have 
the need to design projects, in which case they may use one of the project programs, they also may have the 
need to use word processing. Selling Apples as terminals is much easier when the user has other personal 
computer needs besides mainframe access. 


Apple Personal Computers as Intelligent Terminals 

Since Apple computers are programmable, they can emulate many different types of terminals, the most 
common being the DEC VT-100. 

The IBM 3278 and 3279 display stations are dumb terminals. Replacing them with 

an intelligent terminal which has full stand-alone computing capabilities is a very attractive solution to IBM 
3270 Network users. The most common of the IBM 3278 's and 3279 's can be replaced by an Apple Computer 
and a terminal emulation device. In particular, the IBM 3278 model 2, monochrome, character-only terminal, 
with a typewriter-style keyboard, is easily replaced by an Apple personal computer. 

The biggest advantages and benefits for using personal computers as intelligent terminals instead of using 
dumb terminals are: 

• Cost Advantages 

• Ease of use with Lisa Technology, Mice and Pull-Down Menus 

• Downloading and Remote Storage of Information 

• Remote Processing 

• Creating, Editing and Uploading of Information 

• Elimination of Duplicate Equipment 

• Eliminate Re-keying of Information 

• The Capability of End-Users Writing Their Own Programs 

• Remote Mainframe Program Creation, Testing, Updating. 

• Running Applications Not Available on Mainframe Computers 
Such As: 


Integrated Software Products 
Graphics Programs with Output to Plotters 
Project Management Software 
Some of the other major terminals in the market are listed on the next page: 


Terminal Types: 

The following is a list of the most popular terminal types, beginning with IBM models and followed by mode. 

3178 Models CI and C2. Replacements for the 3278 

3179 Color replacement for the 3279 

3180 Monochrome replacement for 3278 

3275 Discontinued Models 1,2,11,12, 

3276 Control Unit Display Station. Models 1,2,3,4 11,12,13,14. 

3277 Model 2 Display Station 

3278 Models 2 3 4 5 Display Station 
3278 Personal Computer Adapter 

3278 Attachment Option. An adapter in the IBM PC to interface w/ 3278 keyboard 

3279 Color terminal Models S2A, S2B, S3G, 2X, 3X 

3280 Display Station replacement for 3278 
3290 Plasma Information Panel Display 

5150 Personal Computer. 3770, 3101 3278 emulation 

5160 Personal Computer XT/370. Models 568 and 588. 3277 and 3101 emulation. 

5251 Model 11/12 Terminal for the System 34, 36 and 38 

5271 3270 Personal Computer 

Terminals from other manufacturers: 

ADDS Regent 25,60, Viewpoint 60, 78, 90, Executive 80, V210 
Ampex 80,81 

Anderson Jacobson 510,520, APL 
Beehive DM5, DM78, Topper 

Burroughs SR 110, TD830, MT983, ET 1100, ET 2130/2230 
Data General Dasher D-100, D-200, D-400, 6052, 6053 
DEC VT52, VT-61,VT100,101, 102,125, 131, 132, VT200 
Esprit 78,51 

Hazeltine 1400's and 1500's, Esprit 

Hewlett-Packard 86, 125, 2621, 2622A, 2624, 2626, 2641, 2645A 
Honeywell VIP 7700, 7800 

Lear Siegler ADM-3A, ADM-5, ADM 11, ADM 12, ADM 24E, 31 

NCR 501, 796, 7900, Model 3, NCR-1, NCR-4 

Microdata Sequoia and Reality 

Perkin Elmer 1251 

Prime PT45, PST100 

Renex 278, 378,379 

Soroc IQ-120 

Sperry Uniscope 100, U200, UTS 20 

Tektronix 4010 Series 4010,4012,4014,4016 and 4662 Option 31 

Televideo 900 Series 

Teletype Corp TTY KSR 33, 43, 5420 

Texas Instruments 911 

Visual 50,100,200,400,450,550 

Zenith/Heath Z-19/H-19 










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y y y y y y y y y s y y y y y y y y j 
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Figure 4 


Chapter 3 


Following is a description of two solutions, Appleline and Apple Cluster Controller (ACC), for 
using your Apple computer as an IBM 3278-2 terminal. Refer to Figure 4 for a visual 
representation of where they fit in the IBM environment. 

What is Appleline? 

Appleline is a powerful, cost effective solution to terminal emulation and protocol conversion 
device that allows Apple computers to communicate in an IBM mainframe environment. Appleline 
allows Apple computers to emulate the functions of the 3278-Model 2 (3278-2) terminal (with 
typewriter- style keyboard). 

Where does Appleline Fit? 

Appleline is installed at a controller site via a direct coaxial cable connection to an IBM 3274, 3276, 
or integral terminal controller with Type "A" adapters. 3274 controllers can have either Type "A" 
or Type "B" adapters but 3276 controllers will have only Type "A". The protocol used between the 
IBM 3274/76 and the 3278-2 terminal is essentially the same in BSC and SNA/SDLC 
environments. Appleline operates with BSC or SNA/SDLC linked 3274 controllers that are either 
channel-attached or remote. The Apple computer communicating with the 3274 controller via the 
Appleline can be either remotely attached to the Appleline using a full-duplex modem or directly 
attached to Appleline by an RS-232 cable. 

The two configurations described above for Appleline are described in Figure 4. 

Corporations with large 3270 installations will find this solution attractive because it allows them to 
preserve their investment in coaxial cable. Customers who already have existing 3270 controllers 
can simply replace a 32 7 8 display with an Apple and Appleline without changing host software or 
network configuration. 

The Appleline solution expands the potential market for Lisa's and Macintosh's because it allows 
access to channel-attached 3270 controllers. It is estimated that 50% of the installed 3270 
controllers are connected to the IBM mainframe via its channel (direct to host). 

How does Appleline Work? 

Appleline' s on-board, high-speed microprocessor (8x305) handles the 3270 coaxial protocol. A 
second microprocessor handles the RS-232 protocol independently. 

When rhe terminal emulator (VT-100 emulator i.e. LisaTerm or MacTerm) has been activated and 
the user has successfully logged-on to Appleline, the 3270 system protocol will be accepted and 


Appleline's 3278-2 emulator package includes a menu-driven configuration routine. This routine is 
used to establish the communications requirements for the attached device and to select the 
passwords for Appleline. There is no additional software or special network configuration needed 
to accomodate Appleline. 

To aid in the security of the network, multi-level password selection is provided in the 
configuration process. 

Appleline Feature/Benefit Summary: 

Coaxial cable protocol connector which works with IBM 3270 controllers (3274/6). 

Allows Apple Computers to attach to BSC to SNA/SDLC networks. 
Preserves coaxial investment. 

Allows Apple Computers to emulate IBM 3278-2 terminals. 

Transforms a Macintosh, Lisa, Apple II, or Apple /// into a multi-functional 
workstation. Network flexibility. 

Muti-level password scheme: one supervisor and 4 users. 

Built-in security. 


Feature : 

Benefit : 


What is an Apple Cluster Controller? 

The Apple Cluster Controller (ACC) is a stand-alone device manufactured by Protocol Computers, 
Inc. (PCI). This unit allows up to 7 serial devices- Apple Personal Computers, Imagewriters, 
Daisy Wheel Printer, or Scribe Printer to be attached to an IBM 3270 network. These devices are 
connected to the ACC via serial (RS-232C) ports. The ACC "looks like" an IBM 3274 or 3276 
cluster controller to the IBM network. 

How does the Apple Cluster Controller work? 

The ACC communicates to the IBM mainframe with either IBM Binary Synchronous 
Communication (BSC) protocol, or IBM System Network Architecture/Synchronous Data Link 
Control (SNA/SDLC) protocol, (different ACC versions are required) It, in turn, communicates to 
Apple systems using a DEC VT-100 asynchronous ASCII protocol, instead of the 3278 
high-speed coaxial protocol. In simple terms, the ACC acts like an IBM 3271/ 3274/ 3276 cluster 
controller to the IBM mainframe. On the terminal side, the ACC connects to almost any 
asynchronous serial terminal device. The Apple personal computers communicate to the ACC with 
VT- 100 type protocol. 

The ACC is an 8 bit Z-80A-based microcomputer configured with 16KB of ROM and 32KB of 
RAM. Each unit is equipped with its own internal power supply. 

Apple Cluster Controller 
Feature/Benefit Summary: 

Feature: Enables Apple Computers to emulate an IBM 3278-2 terminal and 3287-1 printer 
attached to a 3271,3274, or 3276 cluster controller, either locally or remotely 
attached with either BSC or SDLC protocols. 

Benefit : Allows users access to mainframe database information. 

Feature: Has diagnostic testing built-in for power-up and line monitoring. 

Benefit: User is assured equipment is functioning properly when it is turned on and while it 
is operating. 

Feature: Xon/Xoff flow control for printer operation. 

Benefit: Printer functions at maximum speed without loosing characters. 

Feature: Communication speed up to 9600 bps. 

Benefit: Fast communication between mainframe computers and Apple personal computers. 


Chapter 4 


Selling Appleline and the Apple Cluster Controllers 

Wherever IBM mainframes, Apple personal computers, and 3270 peripherals are found, Appleline and Apple 
Cluster Controllers are a great potential sale. Because of IBM's considerable marketing power, the list of 
qualified organizations includes the vast majority of governments, universities, financial institutions, utilities, 
and the coveted Fortune 1000 companies. The list doesn't stop there, however. The recent popularity of 
IBM's low-cost 4300 series mainframes has delivered 3270 Networks into the hands of tens of thousands of 
smaller concerns as well. In short, 80% of all medium to large corporations are probably prospects for 
Appleline, Apple Cluster Controller and the Apple personal computers it allows to attach. 

Further qualifying should guide you towards the people in these organizations who can benefit most directly 
from Apple personal computers. Current Apple application programs support two major groups of users: 
executives and data processing professionals. 

The executives are decision-makers whose jobs depend upon information. Often the information can be found 
on the organization's mainframe. The ability to access and process that information on their own Apple 
personal computer is extremely attractive to these people. They are prime candidates for Appleline sales. 

The DP people create and use tools to access mainframe information. Though their own needs may not be 
great, they are still tremendously valuable to your sales campaign since they are developing tomorrow's tools 
for the executive. Their support is invaluable, and your greatest successes will come from customers whose 
DP shops are sold on Apples as terminals. 

Once you have qualified the prospects in your area, visit them. If you believe corporate customers will walk 
into your place of business and ask to buy, you will lose out on the majority of corporate customers. These 
people expect to be courted. Despite what some trade publications claim, most corporate purchasing agents are 
not walking into stores to buy their personal computers. 


The most important selling points of Apple computers connected to Applelines 
or Apple Cluster Controllers are: 


1 . Combines easy-to-use Apple personal computers with the IBM mainframe 
environment. (BSC or SNA/SDLC) 

2. Transforms your Macintosh, Lisa, Apple ///, or Apple II into a multi-functional 

3. Network flexibility through dial-up capability (which cannot be done with an IBM 

4. Preserves investment in coaxial cable. 

5. If customer is currently tying ASCII terminals to IBM mainframes through the use of 
NTO software on the front-end controller. (NTO is very expensive and usually 
leased by customer— refer to discussion on NTO in the following section on WHEN 

Apple Cluster Controller: 

1. Combines easy to use Apple personal computers with the IBM mainframe 
environment (BSC or SNA/SDLC). 

2. Provides less expensive solutions to users of IBM mainframe computers. 

3. Provides IBM mainframe users with more flexible network hardware solutions. 

4. Dial-up capability allows users access to the IBM network from remote locations. 

5. If customer is currently tying ASCII terminals to IBM mainframes through the use of 
Network Terminal Option (NTO) software on the front end controller. (NTO is very 
expensive and usually leased by customer—refer to discussion on NTO in the 


When To Sell Appleline: 

Customer has an existing (or is about to purchase) a 3274 or 3276 cluster controller with type A adapters. 

Customer has a channel-attached controller (approximately 50% of IBM mainframe world is 
channel-attached-Refer to Figure 2). ACC's do not connect to 3274's. 

Customer wants a coaxial connection. 

Customer has a fully loaded 3705 or 3725 and wants to connect a personal computer to the IBM network. 

Customer has NTO (defined in glossary) on front-end to handle protocol conversion of ASCII terminals. 
NTO is a very expensive software extension to NCP, which customers lease and Appleline eliminates the 
need for NTO. If an organization has NTO on their front end, they are an excellant prospect for the sale of 
Apple systems. 

When To Sell Apple Cluster Controller: 

Customer is cost-conscious and wants cheapest connect cost per attachment. A 3 port ACC cost's $2,900, 
compared to 3 Appleline 's, which would cost $3,885. 

Customer has 3 or more personal computers in a remote location (not near an IBM 3274/76) and needs to dial 
into an IBM network asychronously. 

Customer wants to replace IBM 3274/76 to have personal computers as terminals on the network. 

Customer has various types of personal computers and wants to hook them all up to the same protocol 

Customer has NTO (defined in glossary) on front-end to handle protocol conversion of ASCII terminals. 
NTO is a very expensive software extension to NCP, which customers lease and Appleline eliminates the 
need for NTO. If an organization has NTO on their front end, they are an excellant prospect for the sale of 
Apple systems. 

Customer needs to hook up printers directly to the converter or Apple computer. 
The following is an APPLE/IBM pricing comparison: 





Hardware (256K) $2420 

IrmaCard $1195 

Total $3420 

Hardware (256K) $4395 

IrmaCard $1195 

Total $5395 
IBM 3270 PC 

Hardware (256K) $3785 

Hardware (512K) $4650 

Hardware (512K/10MB) $6210 



Replacing IBM 
Communications Equipment 

Assumed System Configuration with IBM Equipment: 

Host CPU 

3705 F.E.P. 

6 IBM Cluster 

Same Configuration with Apple Equipment: 

7 3278 Terminals, 
1 3287 Printer 
per Cluster Controller. 
Total: 42 terminals, 
6 printers 

Host CPU 

3705 F.E.P. 

7 Apple Cluster 

6 Macintoshes, 
1 Printer 

per Cluster Controller. 

Total: 42 terminals, 
7 printers 



Incremental Cost Comparison * 

(Software not Included) 

IBM Solution 

Apple Solution 






Fr. End Processor (3705) n/a 



6 Cluster Controllers 

$ 36,000 
($6000 x 6) 

$ 34,300 
($4900 x 7) 

$ 1 ,700 

Terminals (3278's, Mac's) 

$ 96,600 
($2300 x 42) 

($2500 x 42) 

$< 8,400 > 

Printers (IBM's, ASCII) 

$ 36,000 
($6000 x 6) 

$ 4,900 
($700 x 7) 


Total Incremental Cost 

Added Convenience of 
Having a P.C. 






NOTE: Average savings per Apple Cluster Controller: 
$24,400 - 7 = $3,485. (Worth 1 additional PC 
plus software and printer.) 

* Items used in both solutions not included (e.g., 4800 baud modem included in both 
solutions; therefore, no incremental charge for Apple). 



Using AppleLine & Macintosh 

IBM PC & Irmacard 


IBM 3278 


IBM PC (256K) 








IBM 3274 








3278 Emulator 

(Irma, AppleLine) 





Incremental Cost 




NOTE: PC solution is more expensive in comparison to terminal solution. 

But added flexibility of owning a PC will make up for the difference. 



IBM Front - End Processor $46 , 600/ 1 0 lines 

. Comes with 10 to 312 lines. 

IBM 3274 Cluster Controller $ 6,000 

. Can accomodate up to 32 terminals. 
. Typically contains 7 terminals, 1 printer. 
. Cost per port: $750 

IBM 3278-2 Terminal $ 2,300 

IBM 3287 Printer 

Model 1 (80 cps) $ 4,830 

Model 2 (120 cps) $5,150 

* Obtained from IBM product center. Prices do not include 
service or maintenance charges. Lease charges vary by specific 


Comparative Pricing of Personal Computer Systems 
with 3278 Terminal Emulation Capability 

Remote Configuration 

IBM 3178 IBM PC 3270 PC Macintosh 

Terminal $1650 $2505 $5285 $2495 

3278 Emulator $240 $1295 

PC Attachment $2400 

Comm Software $700 $700 $99 
Modems & Cables 

Total $4750 $3950 $5285 $4384 


The Following are the current prices for Appleline and Apple Cluster Controller: 

Appleline: $1,295 
Apple Cluster Controller: 

3 port 
7 port 

$2,900 = $966/port 
$4,900 = $700/port 

Total System Prices - Appleline 

APPLE //e 




$2,495 Apple //e 

$ 100 Super Serial Card 

Access // 
$1,295 Appleline 


$1,295 Lisa 2/10 $5,495 

$ 140 Lisaterminal $ 295 

$ 75 Office System $ 295 

$1,295 Appleline 


$3,890 TOTAL 

$2,795 TOTAL 


Total System Prices for Apple Cluster Controller 
- Per port price using price of 7 port ACC 


APPLE lie 






$ 100 

$ 700 


Apple lie. 

Super Serial Card 



$ 140 

$ 700 


Lisa 2/10 $5,495 

Lisaterminal $ 295 

Office System $ 295 

ACC $ 700 



IBM 3278-2 terminal is currently priced at: $2,382 
IBM 3274 controller is currently priced at: $5,587 
price per port: $ 699 


Chapter S 


The following is a guide to assist you in demonstrating the Appleline and Apple Cluster Controller. 
Preparation and set up procedures are covered to assure your success. Appleline will be covered 
first followed by the Apple Cluster Controller. 


Pre-demo preparation at custodier site 

There are various ways to demo Applelines to your customer. The most effective way is to tie the 
Appleline into the customers existing mainframe environment so that he/she can be assured that the 
two work together. It has a great effect on the customer see his IBM mainframe screens appear on 
the Apple computer. The other way is to subscribe to a timeshare service and tie into it. There is a 
section to follow on tieing into a timeshare service. 

At this point, we will assume you are hooking up to the customers mainframe. There are two 
things you must ensure before you decide on an Appleline demo, they are: 

1. There is a 3274/76 IBM cluster controller with type "A" adapters. 

2. The IBM controller has a port generated for a 3278 model 2 terminal with typewriter keyboard. 

If the answer is no to this question then you must work with the systems programer in charge of 
communications to gen a line for a 3278 model 2 in order to assure proper functioning of the 

When both of the above are ensured you may go on to the actual preparation of the equiment at the 
customer site. 

Setting up the equipment for demo at customer site 

If you will be replacing an existing 3278-2 on the customers system and if the 3278-2 is in 
operation at the time of your set up, ask the customer to properly log-off and power off his/her own 
system to assure that his/her system is not disturbed by you. If the customer has a port properly 
configured but does not have a true 3278-2 plugged in, all the better, you can just plug directly in 
without having to disconnect his/her terminal. 


There are two possible set ups for the Appleline: 

1) . With the Appleline near an Apple computer (Refer to Figure 4) and; 

2) . With the Appleline away from an Apple computer (Refer to Figure 5). 

The configuration with the Appleline near your Apple is covered first and the latter covered 

Equipment needed: 

1 . Appleline 

2. Apple serial cable 

3. Gender changer provided with the Appleline 

4. Coaxial cable up to 5000 ft. (customer usually provides this) 

5. Wall mounting transformer, provided with Appleline 

6. Self-test plug (loop back plug), provided with Appleline 

7. Communications software; the following is a recommended 
software list to be used with the various Apples: 

LISA - Lisaterminal 

Macintosh - Macterminal 

Apple // - Access // 

Apple /// - Access 3270 or Access /// 

In addition to the above items, the following equipment is needed when hooking up Appleline 
away from your Apple: 

1. Set of full duplex, asynchronous modems (Apples modems work 

Installation steps for an 
Appleline near an Apple computer 

1 . Connect coaxial cable to Appleline connector labeled controller. 

2. Connect the other end of the coaxial cable to the 3274/76 configured 
for a 3278-2 terminal with a typewriter keyboard. 

3. Connect wall mounting transformer to port labeled 24V AC and to 
power source in wall, (when Appleline is on it consumes 50 watts 
of power, as much as an electric clock) 

4. Turn on Apple computer and create a document from the appropriate 
terminal software. 

5. Configure terminal software. The following figures demonstrate 
the way set up must look using Lisaterminal and Macterminal. 
Figure 6 is Lisaterminal and Figure 7 and 8 are Macterminal. 
Reference the appropriate terminal manuals if necessary. 


Appleline away from an Apple computer: 

If an Appleline and an Apple computer must be more than 5 meters away from each other (in order 
for the Appleline to reach the IBM Control Unit), they can not be connected with ordinary cable. 
They must communicate by means of telephone lines and a pair of asynchronous modems, like the 
Apple Modems. In this case, attach one Apple Modem to the serial connector on the back of 
Appleline and a second Apple Modem to the serial connector on the back of your Apple computer. 

The Appleline is still connected to the IBM 3274/76 controller via coax cable the same way it was 
described above. For instructions on operating the Apple Modem 300/1200, consult the 
appropriate manual. Once the installation of the modems is complete, the rest of the set up is the 
same as in local connect, eliminating step 3 of installation procedures. 

7. At this point there are a few avenues to take; we will make the assumption the Appleline has 
never been used and therefore there are two procedures which must be performed These are: 

a. Sending the autobaud message 

b. Using the supervisor program 

Once this has been done it is not necessary to do it again. 

Power on the Appleline (switch is located on right side, switch to 1 ) 

Initially the red, green, and yellow LED's (on front) all blink. 

The red LED then goes out. 

Finally, the yellow and green blink alternately; 

Appleline has gone through its self test sucessfully. 

8. a. Press the BREAK key (labeled ENTER to the right of the space bar) 
then press the RETURN key. This is the autobaud message. 

b. Your Appleline will respond by displaying an identification line across the top of your 
screen, followed by this message: 

Press RETURN to begin log-on sequence. 

9. a. Press RETURN. Your Appleline will reply with this prompting: 

Enter Password: 

b. Type APPLES and press RETURN. 

This is the default password to the Appleline's supervisor program. Your Appleline will reply 
with the prompting message: 

AppIeLine has been reset to "factory" settings. 
Please log-on as Appleline SUPERVISOR using the 
supervisor password "APPLES" to get Appleline to your 
particular configuration. 


A terminal type must be selected before you continue. 

Possible selections: 

A - Lisaterminal 
B - Macterminal 
C - Access 3270 
D - VT100 

Your selection [Lisaterminal]: 

The Lisaterminal in brackets means that it is the default setting. For practice we'll change the 
terminal to Macterminal, assuming we are using a Macintosh to communicate and not a Lisa. 

c . Press B and RETURN. 

This tells the Appleline that you are using Macterminal to communicate with it. 
Your Appleline will reply with this prompting message: 

Current terminal type is "Macterminal". Is this correct [Y]? 

d. Press RETURN. 

Pressing RETURN accepts the default response shown inside the brackets 
(in this case the default is Y, which stands for yes). 
Your Appleline will reply with this prompting message: 

Appleline Supervisor Logged-ON 

Possible selections: 

A - Display terminal type and modem settings 
B - Modify terminal type and modem settings 
C - Change USER or SUPERVISOR passwords 
D - Log-off and hang up modem 
E - Log-off and return to logon screen 

Your selection [Log-off and return to log-on screen]: 


At this point you can make any of the above 5 selections to: 

A - Display the communications parameters stored in Appleline 

for the communication between the Apple and Appleline. 
B - Modify the communications parameters stored in Appleline 

for the communication between the Apple and Appleline. 
C - Change the default passwords (supervisor or any of 4 user). 
D - Log-off the supervisor program. 
E - Log-off the supervisor and return to Appleline screen. 

Select option "A" to make sure the default settings meet with your requirements. If the default 
settings do not match your needs, select option "B" and run through all of the currently stored 
options by pressing return to accept or by selecting the proper option and then pressing return to 

Refer to the Appleline User's Manual (Chapter 3 part 1) for specific information about Appleline 
parameter definitions. 

9. At this point you can make selection "E" and log-on to Appleline and 
begin demonstration. 

Demonstrating Appleline: 

1. Press RETURN to begin log-on sequence. Appleline responds by asking 
for your password: 

Enter password: 

2. Type your user password. If no special password has been established through the 
supervisor program you can use any of the 4 provided by the default settings of Appleline; they 


3. When the Appleline recognizes your password, the screen will go blank and then a new 
message will appear on it, transmitted from the IBM mainframe. NOTE: If the Appleline does not 
recognize your password, it will ask to enter it again After 3 attempts, the Appleline will ignore 
further password attempts for 20 seconds. 

4. You are now ready to log-on to the IBM system. To best demonstrate the Apple-to- 
mainframe connection, hand the keyboard over to the customer and let him/her sign-on to the 
mainframe and use his/her own system. 


Using Your Apple Computer Like an IBM Terminal 

Now you can start using your Apple keyboard and monitor screen as if they were the keyboard and 
screen of an IBM Model 3278-2 terminal. The Operator Information Area, by which the IBM 
system informs you of its status, will appear as the bottom line on your (24 line by 80 column) 
Apple screen. (To see the twenty fifth line of the IBM 25 line by 80 column display, press the 
ESCAPE key twice. 

Special IBM Keys 

The Model 3278-2 terminal has keys with special labels on them ("ATTN," "SYS REQ," etc.) 
which do not exist on your Apple keyboard. However, all their functions are still available. To 
achieve the same result with your Apple as you would by pressing these keys on a 3278-2 
terminal, you use a combination of keystrokes. These combinations are listed in Figure 9. In 
addition, Macterminal has a built-in pictoral keypad which allows you to select the IBM keys (also 
referred to as PF keys) by pointing and clicking with the mouse. (Refer to Figure 10). 

5. Logging-off: 

A. Have customer log-off of his/her IBM environment. 

B. There are 3 different log-off procedures you can use 
to terminate a work session with your Appleline, 
depending on what you have been doing and what 
you want to do next. They are as follows: 

a. If you have been working with the mainframe 

and want to quit, just break off communication with 
your Appleline. How you break off communication 
depends on how your Appleline is connected: 

b. If the Appleline is connected directly to your Apple 
computer, simply quit the communication program 
you have been using. If you are not sure how to do 
this, consult the user's manual for your 
communication program. 

c. If it is connected through a pair of asynchronous 
modems like the Apple Modems, tell the modem 
connected to your Apple computer to "hang up"; 
the modem at the other end will then disconnect 
itself from your Appleline. 


If you have been working with the mainframe and want to switch to your Appleline's supervisor 
program, log the mainframe first and then press ESCAPE and then hold down CONTROL and 
press Z. Your Appleline will display the message: 

Appleline User Logged OFF 

but will not discontinue communication. Twenty seconds later, it will automatically return to the 
start of its log-on sequence. At this point you can log back on the Appleline with the supervisor 

Subsequent Demonstrations of Appleline: 

Assuming the default parameters have been defined, subsequent use of Appleline does not require 
resetting the parameters. Therefore, when Appleline receives power, the user will be prompted to 
enter the password. Enter the user password. If the password is acknowledged by Appleline, 
communication with the mainframe is established. 

Problems During and After Installation 

If you have any problems with Appleline in bringing it up during and after installation, there are a 
few things to be aware of. 

Baud Rates: 

1. If a line of garbage appears on the screen, the baud rates on Appleline and the terminal emulator 
do not match. 

Solution: Appleline will autobaud by pressing the break key for several seconds and then hitting 
the enter key. If it doesn't work the first time, try again. 

Framing Error: 

2. Again the baud rates do not match. Try autobauding first. If this does not work, reset 
Appleline with the loopback plug (comes with the Appleline). This will set the baud rate to 4800. 
Set the terminal software to 4800 and try connection again. Following is the procedure for using 
the loopback plug: 

a. Turn your Appleline's power switch to OFF. 

b. Unplug its connection to your apple computer. 

c. Replace the plug that went to your Apple with the loop-back plug. 

d. Turn the power switch ON. 

e. Your Appleline's yellow light should blink slowly to indicate that it is OK. 

Errors on the Mainframe 

After the connection is made, you may still have problems talking to the mainframe. Some 
common problems are: 

X O 2% % - Appears on the status line, the keyboard is locked. 

Solution: The port you're hooked up to is not gen'd for a 3278 mod 2 with typewriter keyboard. 
The typewriter keyboard is the problem. Have your mainframe support re-gen your controller port 
for typewriter keyboards. 


To get around the problem in the meantime, a reset will clear it. This should be CONTROL-R. 

Other strange numbers may appear on the status line. First check and make sure you are connected 
to port 'gened' for a 3278 model 2 or 3279 model 2A with typewriter keyboard. 

Anytime you get a -F, you've typed on the keyboard before the controller is ready for you. A reset 
(control and R) should clear it. 

If your screen is blank with a blinking cursor even after depressing the escape key twice. You are 
not getting a connection to your controller. Controller connection will always give you a 4A, 4B, 
6 A or 6B in the bottom left corner of the screen. 


A - Check coax connection 

B - Check coax wire for breaks 

C - Change coax 

D - Check RS-232 connections 

E - Check RS-232 for breaks 

F - Repair or change RS-232 cable 

Apple Cluster Controller: 

Pre-demo preparation at customer site: 

The following discussion assumes that you will be tying the Apple Cluster Controller (ACC) into 
the customers existing network. If you will be tying into your own system or a timeshare service 
then you will work out your own set-up for the ACC based on your services requirements. Tying 
into your own system has one advantage in that you need only set up the hardware once, however, 
it is not as convincing to the customer as tying into the customers existing network. 

Before installing your Apple Cluster Controller, you should have a discussion with the operator of 
the IBM host computer. He/she will need to inform the host Network Control Program (NCP) of 
the addition of your ACC. Tell the host operator which ACC model you are going to install so that 
he/she can properly SYSGEN the host computer. Changes to the NCP when a Model 76 is added 
are the same as those required when an IBM 3276/12 or 3274 is added. Changes when a Model 
71 is added are the same as those required when an IBM 3276/2 is added. 

You also need to indicate to the systems programmer the type of devices which will be hooked up 
to the ACC. If your computer will be emulating a 3278-2, you indicate to the programmer that the 
device to be attached to the ACC is a 3278-2. If you are hooking up a printer, then you indicate to 
the programmer which ports on the ACC should be reserved for the printer. 

The host operator will inform you of your user ID and password, and of any operating 
characteristics you need to know about in order to properly set up and configure your ACC to 
communicate with the IBM host. 

If the customer is disconnecting an existing, functioning, IBM 3274/6 controller and replacing it 
with an ACC you need not do a gen on their system. In this case you need only set a couple of 
switches on your ACC. Refer to the subsequent discussions on defining the configuration and 
configuring the hardware. 


If the customer has only a channel attached IBM controller, you cannot disconnect their controller 
and hook-up an ACC, the reason being that there is not channel cable connectors on the ACC. 
(If this is the case perhaps the solution is an Appleline). 

Setting up the equipment for demo at customer site 
Equipment Needed: 

1 . Apple Cluster Controller 

2. RS232 cables (one for each computer or printer hooked up) 

3. 2 RJ- 11 phone cords 

4. Power cord 

5. Terminal software; the following list is recommended to be 
used with the various computers: 

Lisa - Lisaterminal 
Macintosh - Macterminal 
Apple // - Access // 
Apple /// - Access /// 

There are three possible set ups for the ACC. 

Deciding on Your Set Up 

Your next step is to decide how you are going to physically set up your ACC and Apple computers 
and/or printers. You need to think about where they will be located and how you will assign 

Device Location 

You can locate your ACC either in the same computer room as the IBM mainframe host to which it 
is connected or in a remote location. The former set up permits the fastest communication with the. 
IBM host. You can connect your ACC to as many as seven Apple computers or six printers, 
either directly or through individual asynchronous modems if you want to place your computers 
and/or printers in remote locations. 

These options give rise to three possible set ups. The IBM mainframe host, the ACC, and the 
Apple computers and/or printers can all be located in the data center. In this situation the ACC is 
directly attached to the front end processor (3705, 3725, etc.). (Refer to Figure 12). 

Alternatively, the IBM host and the ACC can be located in the data center while the Apple 
computers and/or printers can reside in remote locations and be linked to the ACC through 
asynchronous modems. (Refer to Figure 13). 

Apple computers connected through individual modems need not all operate at the same speed; their 
speeds can range from 300 or 1200 bps. 

The ACC with Apple computers attached directly can reside in a location remote from the IBM host 
and be linked to it through a synchronous modem. (Refer to Figure 14). 

Defining The Configuration 

To properly configure your ACC, you need to answer a few questions in advance. 
(Refer to the back panel of you ACC during this discussion) 


SNA/SDLC (or BSC) Port 

The first set of questions pertain to the SNA/SDLC (or BSC) port. 

1 . How will the ACC be connected to the IBM front-end 
processor-directly, or through a modem? 

2. Does the IBM host use NRZI format coding? 

3. What is the polling address of the ACC? (This is normally a 
two-letter hexadecimal code, and should be the same address 
code as that of the IBM front-end processor). 

4. At what speed will the IBM host be operating? (This speed is 
normally specified in bps, and can be 1200, 2400, 4800, or 9600). 

Asynchronous Ports: 

The second set of questions pertain to the asynchronous ports. 

1. Will the ACC be connected to the Apple computer/printer directly, or through a modem? 

2. Do you want to set the port to autospeed? (Automatic speed detection) Autospeed allows the 
incoming data to set the speed of the ACC port. It is used when a port is connected to a 
modem whose data rate may change; usually between 300 and 1200 bps. 

3. At what speed will the port be operating? (This speed can be 300, 1200, 2400, 4800, or 
9600 bps; however, if a port is set to autospeed, then it must be set to 1200 bps). 

4. Will a printer be connected to the port? 

5. If so, what is the delay requirement of the printer? 

This delay allows time for the paper and the print head to move after a carriage return or a line feed. 
This information should be provided in the table of specifications in your printer manual. If you 
connect more than one printer to your ACC, answer this question for the printer requiring the 
shortest delay. 


Configuring The Hardware 

Once you and your customer have determined the configuration requirements, you must configure 
the ACC hardware itself to meet your specifications. Ideally the hardware configuration itself 
should be done before the day of the demo. The set up is not difficult, but it looks a little messy; 
therefore, you may want to spare the customer from this task. 

Refer to the Cluster Controller User's Manual (A9L0301) Part 1: Reference, pages 16-23 for the 
details on the ACC configuration. Configuring the hardware requires you to take off the cover of 
the ACC and set quite a few switchs, etc. The ACC manual diagrams the internals very well. 

NOTE: If you will always be demoing your own ACC via a timesharing network to which you 
have subscribed, you need only set up the ACC once to meet that system's requirements. 

Installation Steps 

1. Place the ACC in its operating position. Make sure that all the cables 
you are planning to use can reach the rear of the unit. 

2. Connect the cable coming from the IBM front-end processor (either directly or through a 
synchronous modem) to the SNA/SDLC (or BSC) port on the rear of the ACC. 

3. If you are planning to use an asynchronous modem to connect either printers or Apple 
computers to the ACC, make sure that the modem is set as follows: 

Orginate mode 
Full duplex 

Speed set to match the printer or computer. 

4. Connect the cables coming from your Apple computers, printers, or modems to the 
asynchronous ports. Secure the cable connectors to the ACC. 

NOTE: There is no need for modem eliminator cables in this set up. 

5. Make sure that the POWER switch is turned OFF. Then plug the power cord into the 
connector marked 1 15 VAC 60 HZ at the rear of the ACC. Plug the other end of the cord 
into the wall outlet. 

6. Set up terminal software. Refer to the diagrams for the terminal set up modes. The only 
variation may be the baud rate used. The location of your ACC and the recipient baud rate 
will determine the baud rate for the terminal software. 


Demonstration of the 
Apple Cluster Controller: 

1 . Power on appropriate computer and create a terminal document with the proper settings. 
(Refer to diagram) (If the ACC is linked to the Apple computer via an asynchronous 
modem you must establish communications with the ACC at this point). 

2. Power on the ACC and wait for self test to finish (green light on front panel will go on when 
complete). The following ACC banner message is displayed on your screen: 

This banner message gives information about your ACC's configuration: 
Message Component Meaning 


SNA for Model 76 

BSC for Model 71 


Number of ports recognized 

by the ACC 


Internal software version number 

Y is a number Z is a letter 


SWO address setting of SNA/SDLC 

or BSC polling address 


SW1 terminal type setting 


SW2 prompting and autospeed 

detection settings 


SW3 printer optionsetting 


Current retransmission count 

from host to ACC 


Current retransmission count 

from ACC to host computer 


Refers to local address of the terminal 

3. The terminal type must be identified to the ACC. Press ESCAPE CONTROL-B and the 
ACC displays a list of terminal types and asks you to choose one. Your response will 
depend on what type of Apple computer you have. 

4. Press ESCAPE CONTROL-D, you will get a prompt: 

«Enter XID:» 

Enter your XID number in response to this prompt 
(this command is for dial-up mode). 


5. If you are communicating from the ACC to the front end via a synchronous modem you 
must establish communication at this time. (Sync modem set-up: plug modem to AC line (set 
switch on front plate to talk, phone line goes to connector on back of modem labeled DIAL 
LINE, plug phone into connector labeled TEL SET on back of modem, power on modem 
and check for dial tone). 

6. Dial phone number if using modem. When you hear tone set modem front plate switch to 
NORMAL mode. 

7. At this point you should get the host's banner screen transmitted to your computer. 

8. Your Apple computer is now an IBM 3278 terminal. If you are logged-on to the customer's 
system you should allow the customer to experiment using his/her own system. 

Special IBM Keys 

Refer to Figure 1 1 for the appropriate Lisa and Mac 3278-2 keyboard equivalents when using the 
ACC. Refer to the Apple Cluster Controller User's Manual for greater detail on the use of the 

Using Timesharing Services for Demos 

Following is a partial list of timesharing services to which you can 
subscribe in order to demonstrate the Apple Cluster Controller and Appleline: 

Boeing Computer Services 


Electronic Data Systems (EDS) 

The greatest advantage to using a timeshare service is that you can control the demo to a greater 
extent. However, it is more believable to the customer if he can tie into his/her existing network. 

Important Demoing Tips and Hints: 

The best demos of Macintosh and Lisa Terminals show the ease of use and consistency of user 
interface, in addition to the integration capability. In order to emphasize these critical selling points, 
the following outlines a demo for Macterminal and Lisaterminal which you can duplicate on your 
respective systems. 


First, create a data-set on your IBM mainframe within the environment that you will be tying into. 
For example, under TSO, you can create a data set under the ISPF editor. Your technical support 
person should be able to do this either by using the help facility under ISPF or by purchasing the 
appropriate user's guide from IBM. In some cases your timeshare service will create a data-set for 
a fee. The data-set should contain a small model (approximately 5x5 matrix) of numbers. It should 
also contain titles over the columns. Once the data set is stored you can use it as the permanent 
information to be copied and then pasted into a calc model. The data-set is on the mainframe and 
therefore can be accessed by Macintosh or Lisa using either the Appleline or ACC. 

To set up the demo refer to the following discussions on Demonstrating Macterminal or 
Demonstrating Lisaterminal in 3270 environment. 

Demonstrating MacTerminal 
in the 3270 Environment 

Create a multiplan model containing titles and formulas to receive the data-set which will be copied 
from the mainframe. Remember to leave enough columns and rows blank (5x5 matrix), in order to 
paste the data successfully. The formulas must be put into the model in advance so that the 
calculations will be performed as the numbers are pasted. 

Create a Macterminal document using the settings outlined in figures 7 & 8. Make your connection 
to the IBM mainframe, following the instructions for demonstrating Appleline or ACC depending 
on which one your using. 

If you are using TSO; 

Type " TSO" 
Type "your user ID" 
Type "your password" 
Type "ISPF" 

Type "your demo data-set name" 

Select the numbers you want copied (5x5 matrix) 

Use the menu keypad PF keys to back out of ISPF. Stress the importance of the user interface and 
ease of use. The keypad feature is unique to Macterminal. 

Logoff of TSO 
Quit Macterminal 
Open Multiplan model 
Select 5x5 matrix 

Paste numbers (columns are automatically formatted when copying from mainframe to 
Macterminal) Change a number or two to show the ability to calculate the pasted data-set. 


Demonstrating LisaTerminal 
in the 3270 Environment: 

The most important aspects to demonstrate on Lisa are the multiple window, multiple session 
capability as well as the ease of use and integration capability. Lisaterminal does not have PF keys 
on the menu, therefore, emphasize the above features. 

Create a LisaTerminal document and set the parameters as outlined in Figure 6. 

Create a Lisacalc document and add the same titles and formulas to fit the data set from the 

Connect to the mainframe using the instructions on demonstrating appleline or ACC, depending on 
which one your using. 

Access the data-set which you have stored on the mainframe in the same manner indicated for 
MacTerminal. LisaTerminal requires you to set tab stops in between columns on the mainframe 
before copying the data-set to be pasted into multiplan. Follow instructions in the Lisaterminal 
manual on copying numbers from mainframe to Lisaterminal. 

Copy the data-set using the copy command on Lisa. 

Open the LisaCalc model which you have previously set up. 

Select the upper left cell contained in your matrix. 

Paste the copied numbers into the model. 


Chapter 6 


The Desktop to Database Dating Decision or 
The Micro to Mainframe Software Marriage 

Typical uses of corporate databases exist in the accounting, design and engineering, distribution, 
manufacturing, sales and marketing, research and development and service departments. When 
considering software for the micro to mainframe marriage, people should consider those packages 
that are easy to use by non-technical personnel: this software should not require a programmer/ 
analyst to operate it. 

Here are a few important areas of software consideration: 

o Access to corporate databases 

Ability to do file transfers and extract partial reports 
Upload and download screens of information 
View and change information as needed 

o Accuracy, Integrity, Security, and Reliability of Information 

Systematic backup of information 

Passwords to restrict access to people with a need to know 
Error checking built into hardware and software 

o Auditibility - being able to trace transactions from input to update to output 
o Application Software - on the Mainframe and on the Micro 

Accounting - A/P, A/R, G/L, Payroll, Inventory 
Communications - Text File Transfer, Graphics Transfer 
Databases - 

Mainframe: IDB, EvIS/DB, EDMS-R, Nomad, Ramis 
Micro: dBase n,III, DB Master, QuickFile 

Decision Support Software / Financial Modeling 

SAS/ETS econometric & modeling software 

Graphics Packages 

Mainframe: SAS/Graph 
Micro: MacPaint, LisaDraw, 


Integrated software packages for multiple use applications 

Appleworks from Apple Computer 
Lotus 1-2-3 and Symphony 
Framework from Ashton-Tate 
3 EZ Pieces from Haba Systems 


Mainframe: IFPS 
Micro: Visicalc 



Specialized and Vertical Market 

Medical, Insurance, Banking, Construction, Legal 


Applewriter from Apple 
Wordstar from Micropro 
Microsoft Word 

Appleworks / 3 EZ Pieces from Apple and Haba Systems 

o Cost controls governing software purchase should be put in place 
o Documentation that is easy to read and comprehensive is a must 
o Operating Environment on Mainframe and on Micro: 

Mainframes and Minis: 



DOS 3.3, CP/M, UNIX, ProDOS, MS-DOS, UCSD p-System 

o Training and support from the dealers and vendors 

o User friendliness of software is of primary importance to first time users. 

On the following pages is list of major vendors of micro to mainframe software: 


Software Products for Micro to Mainframe Links 

The following is a list of compatible and competitive software products for use on either the mainframe end or 
the microcomputer end of a communications link. The reason that both compatible and competitive products 
are given is that products that are one day competitive are the next day compatible in this fast moving business. 
We are trying to get as many of the competitive companies, compatible as soon as possible. 

Apple Computer 
20525 Mariani Ave. 
Cupertino, CA 95014 

Apple Access // $75.00 

Digital Equipment Corportation VT-100, and VT-52 
terminal emulation. 110 to 9600 bps. Includes 
data capture to disk and file transfer. ProDOS 
Based. Macro Capability. Transfers Appleworks 

Apple Access /// $150.00 

Digital Equipment Corportation VT-100, and VT-52 
terminal emulation. 110 to 9600 bps. Includes 
data capture to disk and file transfer. 
Transfers all SOS files. 

Apple Access 3270 

Based on Access /// with PF and PA keys on 
numeric keypad. 

Apple MacTerminal 

Emulate VT-52, VT-100, IBM 3278 and TTY Terminals 
at 50-19,200 bps, 80 or 132 column width, XMODEM 
protocol, Pull down PF keys. Make files into 
tables for spreadsheet. 

Apple LisaTerminal Plus 

VT-52, VT-100 Emulation, Pull down menus, 
Simultaneous Sessions, Cut & Paste, 80 or 132 

ABW Corp. 

P.O. Box M 1047 

Ann Arbor, MI 48106 


Teksim - Tektronics Terminal Emulation 
Addison Wesley 

Applications Software Division 
6 Jacob Way 
Reading, MA 01867 

DSS/F Decision Support Software with Log -On 
communications program 

Applied Data Research 

Route 206 & Orchard Road, CN-8 
Princeton, NJ 08540 


Empire Decision Support Tool 

AT&T Technology Licensing 
P.O. Box 25000 
Greensboro, NC 27420 

BMDP Statistical Software, Inc. 
964 Westwood Dr. 

Cincom Systems 
2300 Montana Ave. 
Cincinnati, OH 45211 
513-661-6000 662-2300 

TIS 4th generation procedural language $250K 
Optional components: Intelligent Query, 
Comprehensive Retrieval, 
Intelligent Reporter, Decision Support. 
Manage User Series: 

Mancalc: $19,500, Mantext, Mangraf: $16,500, 

Computer Associates International 

125 Jerico Turnpike 

Jerico, NY 11753 



Owns IUS/Sorcim 

CA Universe /Relational DBMS $85K-102K 

Communications Research Group 
8939 Jefferson Highway 
Baton Rouge, LA 70809 

BLAST - Blocked Asynchronous Trans 

Computer Solutions Inc. - VisiCorp 
992 South Saratoga -Sunnyvale Rd. 
San Jose, CA 95129 

Comshare , Inc . 

3001 South State Street 

Ann Arbor, MI 48104 


Distributed W is a personal computer 
version of Comshare 's mainframe W Software. 

Context Management Systems 
23864 Hawthorne Blvd. 
Suite 101 

Torrence, CA 90505 

Context MBA integrated software, with built-in 
communications capability 

Cullinet Software 
400 Blue Hill Drive 
Westwood, MA 02090-2198 

IDMS/R Relational database 


On -Line Query 


Digital Equipment Corporation 

146 Main Street 
Maynard, MA 01754 
RSTS/E $6-12K 

Diversified Data Resources 
25 Mitchell Boulevard Suite 7 
San Rafael, CA 94903 

Acorn - Asynchronous Communication 
up to 9600 bps, CRC error checking, 
IBM PC file transfer. 
AcomHFT $3,000 
AcomFT $240 
Acorn $120 

D & B Computing Services 
187 Danbury Rd 
Wilton, CT 06897 
NOMAD 2 $135K 

Elcom Systems Peripherals 

439 Harrison St. Suite A 
Corona, CA 91720 

EPS Consultants 
1 Industrial Drive 
Windham, NH 

FCS-EPS modeling software 

Ergonomic Software, Inc. 
305 East 86th Street 
New York, NY 10028 

Execucom Systems Corp. 
3410 Far West Boulevard 
Austin, TX 78766 

Interactive Financial Planning System (IFPS) 

Goal Seeking, Monte Carlo (risk), Consolidation, 

Sensitivity and Impact Analysis 

Options: Graphics, Foreign File Interface, 

Multiple Linear Regression, 

Runs On: IBM, DEC, Prime, CDC, Honeywell, H-P, 


IFPS Decision Support Software $64K 
IFPS/SENTRY data entry and validation system 

IFPS/DATASPAN transfers data into IFPS files 

IFPS /Personal 

Ferox Microsystems, Inc. 
1201 North Ft. Meyer Drive 
Arlington, VA 22209 

IBM Corporation 
1133 Westchester Ave 
White Plains, NY 10604 

IMS/VS/DB/DC $1,310/Month+ 


0S/VS1, 0S/VS2 (SVS and MVS), 

SSX - Small System Executive/VSE $15-20K 

IE Systems, Inc. 

BiSync Emulation $1195.00 

P.O. Box 359, 98 Main Street 

Newmarket, NH 03857 

(603) 659-5891. 

Enables a CP/M based Apple /// to communicate 
with remote computers using bisynchronous 
protocols. When combined with bisynchronous 
software products from Micro- Integration, an 
Apple /// can emulate an RJE (remote job entry) 
terminal using either 3780, 3741, 2780, and 2770 
protocols or a 3271/77, 3274/78, 3275, and 3276 
bisynchronous device. Cost with serial I/O 
board and bisynchronous software product is 

Informatics General Corporation 

210 Ventura Boulevard 

Woodland Hills, CA 91364 


401 Park Ave. South 

New York, NY 10016 


Answer/DB - VisiAnswer 

TAPS Transaction Processor, Application 

Development Tool 

Relational Datamanager 

Information Builders, Inc. 

1250 Broadway 

New York, NY 10001 


FOCUS $66K $1680/Month Lease 

Intelligent Technologies 
151 University Ave 
Palo Alto, CA 94301 


10505 Sorrento Valley Road 
San Diego, CA 92121 

Lotus Development 
161 First Street 
Cambridge, MA 02141 

1-2-3 on IBM PC, XT, PCjr 3270 PC and PC 

Symphony Plus on Macintosh 
Symphony on 3270/PC 
Symphony on IBM PC, /XT, PCjr 

Management Science America (MSA) , Inc . 
3445 Peachtree Road 
Atlanta, GA 30326 

PeachLink, Executive Peachpak II, DIF Interface 
with Lotus 1-2-3, Multiplan, Visicalc 


A Martin Marietta Data Systems Company 

P.O. Box 2392 

Princeton, "NvTC8540 


RAMIS II $40K-80K 


Time Sharing: ADP, AVCO, Boeing Computer 

Informatics, Litton, Mellonics, Martin 

National CSS, Time Sharing Resources 

RamLink for IBM PC and XT 

DIF for Visicalc and Lotus 123 

McCormack & Dodge 
560 Hillside Avenue 
Needham Heights, MA 02194 
PC Link 

Mesa Graphics 

P.O. Box 506 

Los Almos, NM 87544 



1400A Providence Highway 
Norwood, MA 02062 

Microsoft, Inc. 
10700 Northrup Way 
Bellevue, WA 98004 

Microstuf, Inc. 
1845 The Exchange 
Atlanta, GA 30339 

Micro Tempus, Inc. 

4 Farnham Place Bonaventure 

PO Box 1339 

Montreal, Quebec H5A 1H1 

NCA Corporation 
388 Oakmead Parkway 
Sunnyvale, CA 94086 

On -Line Software International 
Fort Lee, NJ 
OmniLink, OmniMicro 

Oracle Corporation 
2710 Sand Hill Rd 
Menlo Park, CA 94025 
Oracle R - DBMS $12K 

Pathway Design 

177 Worchester Street 

Wellesley, Massachusetts 02181 



Pansophic Systems, Inc. 
709 Enterprise Drive 
Oak Brook, IL 60521 

Ross Systems, Inc. 
1860 Embarcadero Rd 
Palo Alto, CA 94303 

Management Aid for Planning Strategies (MAPS) 
MAPS/DB $12K-30K 

DEC PDP-11, VAX -11 with RSTS/E and VMS 

SAS Institute, Inc. 
SAS Circle, BOX 8000 
Cary, NC 27511 

SAS Statistical Analysis 
SAS/ Graph 

Seed Software 

2300 Walnut Street Suite 734 
Philadelphia, PA 19103 

Simware, Inc. 

Ottawa, Ontario, Canada 

SIM3278, AZPC 2 

Softronics, Inc. 

6626 Prince Edward Place 

Memphis, TN 38119 


Softerm 1 and 2 - Terminal emulation software 
for the Apple lie. 

Software AG of North America. 

11800 Sunrise Valley Drive 
Reston, Virginia 22091 

Natural - 4th generation language 
ADABAS - Adaptable Data Base System 
Runs on S/360, S/370, 303X, 4300, most 
compatibles. Runs under DOS, DOS/VS, 
D0S/VSE,0S, OS/ VS. 

SPSS, Inc. 

444 Michigan Ave. Suite 3000 
Chicago, IL 60611 

SPSS Data Analysis System 

Tominy, Inc. 
4221 Malsbary Rd. 

Cinncinati, OH 45242 


Data Base -Plus 

Tymnet /Tymshare, Inc 
2710 Orchard Parkway 
San Jose, CA 95134 

United Software Industries 
ASCII Express "Professional" 
1880 Century Park East Suite 311 
Los Angeles, CA 90067 


2726 S. Moline Ct. 
Aurora, CO 80014 


2895 Zanker Road 

San Jose, CA 95134 


VisiAnswer, VisiLink, Visiterm 

VM Personal Computing 
60 E. 42nd Street 
New York, NY 10165 
New York, N.Y. 
Please, Relay 


Chapter 7 


The following is a list of manufacturers of competitive hardware for connecting personal computers 
to mini and mainframe computers. 

AT&T Information Systems 
P.O. Box 13970 
Orlando, FL 32859 

Personal Computers with 3270 capability 

AT&T Communications 


Value Added Network 

3270 emulation in the phone lines 

Avatar/ 3R Computers 
18 Lyman Street 
Westboro, MA 01581 

PA-1000 PA-1500 Protocol Converters 

AST Research, Inc. 
Irvine, CA 

Protocol Converters for IBM PC 

Base 2 (PTY) LTD. 
P.O. Box 56126 

South Africa 
Telex 4-22183 S.A. 
Protocol Conversion Software 

Black Box Corp 
Protocol Converters 

Boeing Computer Services 
Data Network Services 
Value Added Networks 

Burroughs Corporation 
Burroughs Place 
Detroit, MI 48232 
3270 Terminals 

Braegen Corp. 

3340 East La Palma Ave. 

Anaheim, CA 92086 

3270 Emulation with PC added-on 

Carterphone Communications Corp. 
Dallas, TX 
Protocol Converters 

Computer Communications, Inc. 

2610 Columbia Street 

Torrence, CA 90503 



Protocol Converters 

C. Itoh Electronics 

CIE Terminals 

2505 McCabe Way 

Irvine, CA 92714-6297 


800-432-3687 in Calif. 

3270 Terminals with PC's added-on 


A Motorola Information Systems company 

20 Cabot Blvd. 

Mansfield, MA 02048 

High Speed Synchronous Modems 

Desktop computers with 3270, 3780 protocols 

206 East Park 
Lebanon, OH 45036 


5710 Paradise Drive 

Corte Madera, CA 94925 


Protocol Converters 

Control Data 

8100 34th Avenue South 

Minneapolis, MN 55440 


3270 Terminals 

Core Technology Corp. 
1000 University Drive 
Suite 109 

Rochester, MI 48063 



3606 W. Bayshore Rd. 
Palo Alto, CA 94303 

CXC Corporation 

2852 Alton 

Irvine, CA 92714 


PBX with 3270 emulation 

Data General Corp. 
4400 Computer Drive 
Westboro, MA 02090 

DataNetComm Inc. 

P.O. Box 881283 

San Francisco, CA 94188-1283 

Protocol Conversion Devices 


120 W Wieuca Road, N.E. 
Atlanta, GA 30042 
Protocol Converters 

Digital Equipment Corporation 
146 Main Street 
Maynard, MA 01754 
VT-100/200 Terminals 

Digital Communications Associates, Inc. (DCA) 

303 Technology Park 

Norcross, GA 30092 


Protcol Converters 

Elcom Systems Peripherals 
439 Harrision Street, Suite A 
Corona, CA 91720 
Protocol Converters 

Fibronics International Inc. 
218 W. Main Street 
Hyannis, MA 02601 

Forte Data Systems 
1500 Norman Avenue 
Santa Clara, CA 95050 
Protocol Converters 

Gateway Communications, Inc. 
16782 Redhill Ave. 
Irvine, CA 92714 

General Electric Information Services Company (GEISCO) 

401 North Washington Street 

Rockville, MD 20850 

Value Added Network with 3270 emulation 

GTE Spacenet Corporation 
1700 Old Meadow Road 
McLean VA 22102 

Value Added Network with 3270 emulation 


National Accounts Division 
1133 Westchester Avenue 
White Plains, NY 10601 
3270 Systems 


National Marketing Division 
4111 Northside Parkway 
P.O. Box 2150 
Atlanta, GA 30055 
3270 Systems 


Entry Systems Division 
P.O. Box 1328 
Boca Raton, FL 33432 
3270 Systems 

IDEAssociates, Inc. 

7 Oak Park Drive 

Bedford, MA 01730 

Protocol Converters for IBM PC 

Informer Computer Terminals, Inc. 
22936 Mill Creek Road 
Laguna Hills, CA 92653 
3270 Terminals 

InteCom, Inc. 
601 InteCom Drive 
Allen, TX 75002 

PBX with built-in 3270 emulation 

ITT Courier 

1515 West 114th Street 

Tempe, AZ 


3270 Terminals, IBM PC work-alikes 

JBM Electronics 

6020 N. Lindbergh Blvd 

St. Louis, Missouri 63042 

Lee Data Corporation 
7075 Flying Cloud Drive 
Minneapolis, MN 55344 
3270 Terminals 

Lemcom Systems, Inc. 
2104 W. Peoria Avenue 
Phoenix, AZ 85029 

Le Roux International 
3090 Acushnet Avenue 
New Bedford, MA 02745 

Local Data 
2701 Toledo St. 
Suite 706 

Torrance, CA 90503 


MA/Comm Data Communications Group 
11717 Exploration Lane 
Germantown, MD 20874-9989 
Modems, Multiplexers, Error Controllers 

Memorex Corporaton 

1125 Memorex Drive 

Santa Clara, CA 95052 

3270 Terminals, Cluster Controllers 

NCR Corporation 
Box 606 

Dayton, OH 45479 
Mainframes, Terminals, PC's 

NCR Comten 
2700 Snelling Ave. North 
St. Paul, MN 55113 
Communications Equipment 

Northern Telecom 

259 Cumberland Bend 

Nashville, TN 37228 

PBX's with built-in protocol conversion 

Northern Telecom 
Business Communications Systems 
1001 East Arapaho Road 
Richardson, TX 75081 

Northern Telecom 
Terminal Systems Division 
Data Park, P.O. Box 1222 
Minneapolis, MN 55405 

Phaze Information Machines, Corp. 
7650 East Redfield Road 
Scottsdale, AZ 85260 

Phaser Systems, Inc. 

24 California St. 

San Francisco, CA 94111 


PCI/ Protocol Computers, Inc. 
6150 Canoga Avenue 
Woodland Hills, CA 91367-3773 
800^23-5904 213-716-5500 in Calif. 

Personal Systems Technology, Inc. 

Persyst Products 

15801 Rockfield Blvd Suite A 

Irvine, CA 92714 


Protocol Converters 

Renex Corporation 
6901 Old Keene Mill Road 
Springfield, VA 22150 
Protocol Converters 


4900 Old Ironsides Drive, M/S 626 
Santa Clara, CA 95050 

PBX's with built-in 3270 emulation 

Rixon, Inc. 

2120 Industrial Parkway 
Silver Spring, Maryland 20904 
Synchronous Modems 

Sperry / Univac 
Township Line & Jolly Rd. 
P.O. Box 500 
Blue Bell, PA 19424 

Mainframes, Communications Equipment 

Teletype Corporation 

5555 Touhy Ave. Dept 3223-E 

Skokie, IL 60077 


3270 Terminals 

Thomas Engineering 
1040 Oak Grove Road 
Concord, CA 94518 
Protocol Converters 

Tymnet, Inc. 

Division of MacDonald-Douglas 
2710 Orchard Parkway 
San Jose, CA 95134 
Value Added Network 


Division of GTE 

Network Systems & International Services 

8229 Boone Boulevard 

Vienna, VA 22180 


Value Added Network 

Uninet, Inc. 

10951 Lake view Ave. 

Lenexa, KS 62219 


Value Added Network 

Universal Data Systems 

A Motorola Information Systems company 

5000 Bradford Drive 

Huntsville, AL 35805 

Synchronous modems 

Viking Associates 
2726 S. Moline Court 
Aurora, CO 80014 
Protocol Converters 

Wang Laboratories, Inc. 
One Industrial Avenue 
Lowell, MA 01851 

Minicomputers, Terminals, 3270 emulation 

Winterh alter, Inc. 

3853 Research Park Drive 

P.O. Box 2180 

Ann Arbor, MI 48106 


313-662-2002 in Michigan 

Protocol Converters 


Chapter 8 













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Glossary and Abbreviations 


Generally the obtaining of data, from a storage 
device or peripheral. 

Access Method 

The technique and/or program code for moving 
data between main storage and I/O devices. 
Existing access methods include: basic access 
method, basic direct access method, basic 
indexed sequential access method, basic 
partitioned access method, basic sequential 
access method, basic telecommunications access 
method, queued indexed sequential access method, 
queued sequential access method, queued 
telecommunications access method, 
telecommunications access method. 

Access Time 

The time interval between when data is called 
for or requested to be stored in a storage 
device and when delivery or storage is 

"Acknowledge Character" (ACK) 

A transmission control character transmitted 
by a station as an affirmative response to the 
station with which a connection has been set up. 
An acknowledge character may also be used as an 
accuracy control character. 


A word formed from the first letter (or letters) 
of the words in a phrase or name. 

Acoustic Coupler 

A type of low -speed modem frequently used with 
portable terminals. It sends and receives data 
using a conventional telephone handset and does 
not require a permanent connection to the line. 


A coded representation of the destination 
of data, or of their originating terminal. 
Multiple terminals on one communication line, 
for example, must have unique addresses. 
Telegraph messages reaching a switching 
center carry an address before their text 
to indicate the destination of the message. 

Advanced Communications 

Function /Telecommunications Access Method 


A high-level access method which supports a 
large selection of terminal (BSC, S/S, Local 
Attachment and SDLC) and offers support for 
most MVS and VS1 applications. 

Advanced Communications Function/Virtual 
Telecommunications Access Method (ACF/VTAM) 

Provides an "operating system" for the network. 
Its functions are analogous to the function of 
a host operating system in terms of resource 
sharing and logical handling of user requests. 

Advanced Data Communications Control Protocol 

A communications protocol endorsed by the 
American National Standards Institute. It is a 
bit -oriented protocol. 

Advanced Program to Program Communication (APPC) 

American National Standard Code for Information 
Interchange. (ASCII) 

(1) A coded character set consisting of 7 -bit 
coded characters (8 bits including parity 
check) , used for information interchange among 
data processing systems, data communication 
systems, and associated equipment. The ASCII 
set consists of alphanumeric characters, control 
characters, and graphic characters. (2) A wide 
ly used asynchronous protocol based on ASCII 


Referring or pertaining to a signaling tech- 
nique in which a transmission is conveyed by 
modulating (varying) the frequency, amplitude, 
or phase of a carrier. An analog signal is 
typified by a continuous wavelike pattern. 
Analog signaling is generic to the public 
switched telephone network, as well as to 
certain other audio frequency and radio 
frequency facilities. A digital baseband 
signal generated by a business machine must be 
converted to analog form in order to transmit 
that signal over an analog facility, e.g., a 
voice -grade telephone line. 

Applicaton Layer 

In SNA, the functional layer of each individual 
session in which the end user's application 
program is executed. 


Occuring without a regular or predictable time 
relationship to a specified event, e.g., the 
transmission of characters one at a time as 
they are keyed. Contrast with synchronous. 

Asynchronous Transmission 

Digital data transmission format in which start 
and stop bits identify the beginning and ending 
of each character. Also called start -stop bits. 


Auto -Answer 


A modem capability that allows automatic 
"pick-up" when the phone rings. 

Auto -Dial 

The ability to automatically make a connection 
with another modem. 

Automatic Send Receive 

A teleprinter terminal with paper tape or 
magnetic tape devices, or editable internal 
memory. Refers to any keyboard terminal with 
off-line storage capabilities that permits a 
message to be generated off-line for later 


A measure of data rate, often used to denote 
bits per second. A baud is equal to the number 
of discrete conditions or signal events per 
second. There is disagreement over the 
appropriate use of this word, since at speeds 
above the 2400bps, the baud rate does not equal 
the data rate in bits per second. 

Balanced Circuit 

A circuit terminated by a network whose 
impedance balances the impedance of the line 
so that the return losses are negligible. 


The frequency band occupied by information - 
bearing signals before they are combined with a 
carrier in the modulation process. 

Basic Telecommunications Access Method (BTAM) 

An access method that permits read/write 
communications with remote devices. 

Batch Processing 

A technique of data processing in which jobs are 
collected and grouped before processing. Data 
is collected over a period of time and then 
submitted to the host machine for processing. 

Batched Job 

A job that is grouped with other jobs as part of 
an input stream to a a computer system. 


A numbering system using 2 as its base and only 
the symbols 0 and 1. It is especially well 
adapted to computer use since 0 and 1 can be 
represented as on and off or negative charges 
and positive charges. The binary digits appear 
in strings of O's and l's. Most computers do 
their calculations in binary. 

The commonly used abbreviation for binary digit. 
A bit is the smallest unit of information 
recognized by a computer, and is a unit of 
information corresponding to a choice between 
two alternatives (such as one and zero) . 

Bits Per Second (bps) 

The basic unit of data communications rate 
measurement. Usually refers to rate of 
information bits transmitted. 

Bit Error Rate Testing (BERT) 

Testing a data line with a pattern of bits which 
are compared before and after the transmission 
to detect errors. 

Bit Rate 

The rate at which bits (binary digits) are 
transmitted over a communications path. 
Normally expressed in bits per second (bps) . 
The bit rate is not to be confused with the data 
signaling rate (Baud) which measures the rate 
of signal changes being transmitted. 


A group of characters, bytes, or words 
communicated as a unit. 


A condition in a switching system in which 
no paths or circuits are available to complete 
a call and a busy tone is returned to the 
calling party. In this situation there is no 
alternative but to hang up and try the call 
again. Also referred to as denial or busy 

Block Error Rate Testing (BLERT) 

Testing a data line with groups of information 
arranged into transmission blocks for error 

Burrough's Data Link Control (BDLC) 

A bit -oriented protocol. 

Binary Coded Decimal (BCD) 

A binary-coded notation in which each of 
the decimal digits is represented by a binary 
numeral, e.g., in binary -coded decimal notation 
that uses the weights 8-4-2-1, the number 
"twenty three" is represented by 0010 0011 
(compare its representation 10111 in the pure 
binary numeration system) . 


Binary Synchronous Communications 

A half -duplex, character-oriented data commu- 
nications protocol originated by IBM in 1964. 
It included control characters and procedures 
for controlling the establishment of a valid 
connection and the transfer of data. Also 
called bisync and BSC. Although still enjoying 
widespread usage, it is being replaced by 
IBM's more efficient protocol, SDLC. 

Bell Operating Companies (BOC's) 

The 7 Regional Operating Companies created since 
divistiture of AT&T. 


The act of going around the local central 
telephone company office, with customer premises 


A signal of known characteristics (for example, 
frequency) that is altered (modulated) to 
transmit information. Knowing the expected 
signal, the receiving terminal interprets any 
change in signal as information. Changes to the 
signal made by outside influences (noise) can 
cause the receiving terminal to misinterpret 
the information transmitted. 


A type of private branch exchange service 
where incoming calls may be dialed direct to 
extensions without operator assistance. 
Out -going and intercom calls are dialed by 
extension users. 


(1) In data communications, a one-way path along 
which signals can be sent between two or more 
points. Contrast with circuit. (2) In tele- 
communications, a transmission path (may be 
one-way or two-way, depending on the channel) 
between two or more points. Provided by a 
common carrier; also called a link, line, 
circuit, or facility. 


A language unit composed of a group of bits. 

Character Error Rate Testing (CERT) 

Testing a data line with test characters to 
determine error performance. 


A two-way path along which signals can be sent 
between two or more points. Also see channel. 


Time synchronizing of communications 


A group of user terminals co- located and con- 
nected to a single controller through which each 
terminal is afforded the opportunity to access a 
single communication line. 

Cluster Control Unit 

A device, such as the 3274 Control Unit, that 
can control the input/output operations of more 
than one terminal, such as a group (cluster) of 
3278 Display Stations. 

Common Carrier 

A company that furnishes communication ser- 
vices to the general public at public regu- 
lated prices. In data communications, a pub- 
lic utility company that is recognized by an 
appropriate regulatory agency as having a vested 
interest and responsibility in furnishing 
communication services to the general public; 
Bell, MCI, GTE. 


Transmission of intelligence between points of 
origin and reception without alteration of 
sequence or structure of the information 
content. See also data communication. 

Communication Controller 

A type of communications control unit whose 
operations are controlled by a program stored 
and executed in the unit. Examples are the IBM 
3704 and 3705 Communication Controllers. 

Computerized Branch Exchange (CBX) 

A telephone switch that controlled by a 

Computerized in -house telephone system. 

An electronic device which interfaces in a 
store -and -forward mode with multiple low -speed 
communication lines at a message level and 
then retransmits those messages via one or more 
high-speed communications lines to a processing 

Consultative Committee on International 
Telephone and Telegraph (CCITT) 

This United Nations group is currently setting 
up worldwide communication standards. 



Competition by users for the use of the same 
communications facilities; a method of line 
control in which terminals request or bid to 
transmit. If the channel is not free, the 
terminals must wait until the channel is free. 

Control Character 

A coded character which does not print but 
initiates some kind of machine function such as 
a carrier return. 

Conversational Monitor System (CMS) 

A component of VM/370 which provides a high 
performance, interactive computing system 
suitable for general problem solving and program 
development and which can serve as a base for 
interactive applications. 

Customer Information Control System (CICS) 

An IBM data base/data communication (DB/DC) 
program product that provides an interface 
between the operating system access methods and 
applications programs to allow remote or local 
display terminal interaction with the data base 
in the central processor. Different versions 
include Time Management facilities and support 
for bisync, dial-up, PL/1 support and expanded 
data base control items such as file browsing, 
dynamic file open and close. 


A device capable of converting impulses from one 
mode to another, such as analog to digital, or 
parallel to serial, or from one code to another. 

Cyclic Redundancy Check 

A powerful error detection technique. Using a 
polynomial, a series of two 8- bit block check 
characters are generated that represent the 
entire block of data. The block check characters 
are incorporated into the transmission frame, 
then checked at the receiving end. 


Any type of information, such as numbers, 
letters, or symbols that can be processed by 
a computer. 

Data Access Arrangement (DAA) 

A telephone -switching system protective 
device used to attach non- telephone- company - 
manufactured equipment to the carrier network. 

Data Communication Equipment (DCE) 

The equipment installed at the user's premises 
which provides all the functions required to 
establish, maintain and terminate a connection, 
the signal conversion and coding between the 
data terminal equipment and the common carrier's 
line, e. g., data set, modem. 

Data Communications 

A broad term covering any exchange of infor- 
mation between computers or similar systems 
over telephone lines. 

Data Compression 

A technique that saves storage space by 
eliminating gaps, empty fields, redundancies, 
or unnecessary data to shorten the length of 
records or blocks. For data transmission a byte 
string of data is transmitted as a count plus a 
string value. 

Data Integrity 

A performance measure based on the rate of 
undetected errors. See also integrity. 

Data Language II (DL/I) 

Used for reducing application program and file 
maintenance while allowing more sharing of data 
by multiple programs and users. 

Data Link 

The physical connection and the connection 
protocols between units that exchange data over 
a communication line. 

Dataphone Digital Service (DDS) 

An AT&T leased line service offering digital 
transmission at speeds ranging from 2400 bps to 
1.544M bps. 

Data Terminal 

Data processing equipment that is used for 
collection, use, or transfer of data. 

Data Terminal Equipment (DTE) 

Equipment comprising the data source, the 
data sink, or both that provides for the commu- 
nication control function (protocol) . Data 
termination equipment is actually any piece of 
equipment at which a communications path begins 
or ends. 

Decibel (dB) 

Power level measurment unit. 1/10 Bel. 



The opposite of modulation; the conversion of 
a signal from analog to its original (e.g., 
digital) form. 

Dial-up Line 

A communications circuit that is established by 
a switched circuit connection. 


A pair of bits treated as one information 
element. In modulation schemes with more than 
two states, multiple bits are represented by 
each state. The term "dibit" originally was 
used for the AT&T 201 series of modems, which 
used four phase states to encode information; 
each state could therefore represent two bits. 


A character used to designate a quantity. The 
decimal system uses the digits 0-9; binary 
sytem: 0-1; hexadecimal system: 0-F. See also 
binary digit. 


Referring or pertaining to a signaling technique 
in which a transmission is conveyed by gener- 
ating pulses of electromagnetic energy in 
a discontinuous (i.e., on/off) coded pattern 
representing, for example, bits in a data 
stream. Contrast with analog. 

Digital Data Communications Message Protocol 

A Digital Equipment Corporation data 
communications line protocol. 

Digital Service Unit or Data Service Unit (DSU) 

A device for amplifying, timing and converting 
unipolar digital signals into bipolar digital 
signals suitable for transmission to the Central 

Direct Access Storage Device (DASD) 

A device in which the access time is effectively 
independent of the location of 
the data. 

Direct Distance Dialing (DDD) 

A means for making long-distance telephone calls 
over the switched telephone network without 
operator assistance. 

Disk Operating System/Virtual Storage Extended 

Disk resident virtual storage operating system. 
Runs on S/370 (Model 115-158), 
3031 and 43XX. 

Distributed Office Support System (DISOSS) 

A collection of systems and software that is 
aimed at integrating the various pieces of the 
IBM office product. It is the foundation for 
much of the work in the DIA/DCA area. 

DPPX/Data Base and Transaction Management System 

An online transaction system which runs on the 
8100 under DPPX. Similar to CICS/VS for 370 
users . 

DPPX/ Interactive Productivity Facility 


A program product which provides a simplified, 
full -screen, interactive interface to the DPPX 
command facility. 

Document Interchange Architecture (DIA) 

An access protocol to allow the transmission 
of documents over an SNA type of network. It 
relies heavily on the Advanced Program to 
Program Communication (APPC) technique. 

Document Content Architecture (DCA) 

A method of defining the rules and format of 
documents which are known to programs and other 
systems. This scheme requires the program to 
format and store or transmit known formats 
between applications. 

Dual In -Line Package (DIP) 

The most common integrated circuit package 
having dual, or parallel rows of pins at 0.1 
inch intervals. 

Dumb Terminal 

A device with a keyboard for inputting data and 
a display screen for the output of data but 
lacking local processing capability. A dumb 
terminal provides remote access to a computer 
but can not itself be programmed. 


(1) (ISO) In data communication, pertaining to a 
simultaneous two-way independent transmission in 
both directions. Synonymous with full duplex. 

(2) Contrast with half -duplex. 


Electronics Industries Association (EIA) 

A standards organization specializing in 
electrical and functional characteristics of 
interface equipment. 

Electronic Switching System (ESS) 

A type of telephone switching system which uses 
a special -purpose stored program digital 
computer to direct and control the switching 
operation. ESS permits the provision of custom 
calling services such as speed dialing, call 
transfer, three way calling, etc. 


The use of programming techniques and special 
machine features to permit a computing system 
to execute programs written for another system. 
This form of imitation is primarily done via 
software. Emulation is generally used to 
minimize the impact of conversion from one 
computer system to another, and is used to 
continue the use of production programs- -as 
opposed to "simulation" which is used to study 
the operational characteristics of another 
(possibly theoretical) system. 

Error Detection and Correction 

A system employing an error detecting code and 
so arranged that a signal detected as being in 
error automatically initiates a request for 

Extended Binary -Coded Decimal Interchange Code 

A coded character set consisting of 8 -bit coded 
characters. EBCDIC is the usual code generated 
by synchronous IBM devices. 

Facsimile (FAX) 

A system for the transmission of images. 
The image is scanned at the transmitter, 
recontructed at the receiving station, and 
duplicated on some form of paper. 

Federal Communication Commission (FCC) 

A board of commissioners empowered to regulate 
all interstate communications between the U.S. 
and abroad. 

Foreign Exchange Service (FEX) 

A service that connects a customer's telephone 
to a remote exchange. This service provides the 
equivalent of local telephone service to and 
from the distant exchange. 

Forward error correction (FEC) 

The technique which provides for the transmittal 
of additional information with the original bit 
stream such that if an error is detected the 
correct information can be recreated at the 
receiving end without a retransmission. 

Four -wire Channel 

Provision of two wire pairs (or logical 
equivalent) for simultaneous two-way 

Four -wire Circuits 

Indicates the capability of the switching system 
to accomodate connections to special A -wire 

Framing bits 

In data transmission, noninformation carrying 
bits used to make posssible the separation of 
characters in a bit stream. Synonymous with 
sync bits. 

Frequency division multiplexing (FMD) 

Division of the available transmission frequency 
range into narrower bands eachof which is used 
for separate channels. 

Frequency modulation (FM) 

A method of transmission whereby the frequency 
of the carrier wave is changed to correspond to 
changes in the wave signal. 

Frequency shift keying (FSK) 

A method of frequency modulation in which 
frequency is made to vary at significant 
instants by smooth as well as abrupt 

Front end 

An auxiliary computer system which performs 
network control operatons, relieving the host 
computer system to do data processing. 

Full /full duplex 

A protocol which, when operating on a multidrop 
line, is capable of transmitting from the master 
location to one of the slave sites and, at the 
same time, the master location can receive a 
transmission from a different slave site on the 
same line. 

Front -end Processor 

A communications processor to regulate the flow 
of information between the host computer and 
other elements of a communications system. 


Full /full duplex 


A protocol which, when operating on a multidrop 
line, is capable of transmitting from the master 
location to one of the slave sites and, at the 
same time, the master location can receive a 
transmission from a different slave site on the 
same line. 

Front -end Processor 

A communications processor to regulate the flow 
of information between the hostcomputer and 
other elements of a communications system. 

Full -duplex 

Pertaining to the capability to transmit in two 
directions simultaneously. 


A communications satellite orbit at the correct 
distance from the earth and at the correct speed 
to appear fixed in space as the earth rotates. 

Half -duplex 

Pertaining to the capability to transmit in two 
directions but not simultaneously. 


An exchange of control sequences between two 
locations to set up the correct parameters for 

Houston Automatic Spooling Priority (HASP) 

A computer program that provides supplementary 
job management, data management, and task 
management functions such as control of job 
flow, ordering of tasks, and spooling. 

High level Data Link Control (HDLC) 

An ISO standard data communications line 

Information Management System/Virtual System 

IBM data base management software system that 
also provides communications monitor functions. 

Integrated Services Digital Network (ISDN) 

Intelligent Terminal 

A terminal that can do editing, error checking 
and is programmable. 

Interactive Processing 

The exchange of information and control between 
the user and a computer on a current basis; not 
in batch mode. Also called conversational. 

A shared boundary. An interface might be a 
hardware component to link two devices or it 
might be a portion of storage or registers 
accessed by two or more computer programs. 

International Standards Organization (ISO) 

An international federation of national 
standards organizations which also becomes 
involved in developing standards, including 
communication standards. 

Institute of Electrical and Electronic Engineers 

Job Entry Subsystem (JES) 

A system facility for spooling, job queuing, and 
managing I/O under MVS. 

Leased Line/Private Line /Dedicated Line 

A communications line for voice and/or data 
leased from a communcations carrier on a monthly 

Limited Distance Modem 

A short-haul modem or line driver that operates 
over a limited distance. Some limited distance 
modems operate at higher speeds than modems 
that are designed for use over analog telephone 
facilities, since line conditions can be better 

Line Driver 

An alternative device to a modem when trans- 
mitting via EIA cable over short distances, 
(e.g., a few hundred feet.) The line driver 
amplifies the signal and reshapes distorted 

Line Hit 

A disturbance causing a detectable error on a 
communications line. 

Line protocol 

A control program used to perform data 
communications functions over network lines. 
Consists of both handshaking and line -control 
functions which move the data between transmit 
and receive locations. 

Local Area Network 

A user -owned, user -operated, high -volume data 
transmission facility connecting a number of 
communicating devices (computers, terminals, 
word processors, printers, mass storage units, 
robots, etc.) within a single building or campus 
of buildings. 

Loop Current 

A teletypewriter to line interface and operating 
technique without modems. 


Management Information System (MIS) 

(1) Management performed with the aid of auto- 
matic data processing. (2) An information 
system designed to aid in the performance 
of management functions. 


The signal (communications channel state) 
corresponding to a binary one. The marking 
condition exists when current flows (current - 
loop channel) or when the voltage is more 
negative than -3 volts (EIA RS-232-C channel). 

Metallic circuit 

A physical wire between two points as opposed 
to microwave or fiber optics. 

Modem Eliminator 

A device for connecting two DTE interfaces 
physically and logically without requiring 
intervening modems. 

Multidrop or Multipoint 

A single line which can have one or more 
terminals connected. Communication is done 
on a time shared basis. 


Combines signals of multiple channels into one 
channel . 


A device to convert computer signals into a form 
that is suitable for transmission over telephone 


The application of information onto a carrier 
signal by varying one or more of the signal's 
basic characteristics (frequency, amplitude or 
phase) ; the conversion of a signal from its 
original (e.g., digital) format to analog 
format . 

Multiple Virtual Storage (MVS) 

An alternate name for 0S/VS2, release 2. 

"Negative Acknowledge" Character (NAK) 

A transmission control character that indicates 
a block of data was received incorrectly. 


A computer communications system consisting 
of one or more terminals communicating with 
a single host computer system, which acts as 
the network control component through internal 
programming or perhaps through a front end 
processor. The chief characteristic of a 
network is the single, controlling host computer 
system, which may include multiple processors. 
The general use of the word "network" to mean a 
collection of interconnected components is no 
longer precise, just as the word "system" no 
longer carries the connotation of close 
proximity of components. 

Network Address 

In SNA, the address, consisting of subarea and 
element subfields, that uniquely identifies a 
link or the location of a network addressable 
unit. The conversion from a local address to a 
network address, or vice versa, is accomplished 
as part of the boundary function in the node 
attached to a cluster controller node or a 
terminal node. 

Network Control Program (NCP) 

Resides in the 3705 Communications Controller 
and provides the physical management of the 
communicaton network. Its main function is to 
control attached lines and terminals, perform 
error recovery and route data through the 
network. NCP communicates with the host through 
VTAM, EXTM, ACP, TCAM or through another NCP. 

Network Terminal Option (NTO) 

A software protocol converter that resides in 
the front -end processor 

Non- Return -To -Zero (NRZ) 

Pertains to both magnetic recording and 

Non - Return - To - Zero - Inverted (NRZI) 
Non -Switched Lines 

A communications link which is permanently 
installed between two points. 

Off Hook 

Activated (in regard to a telephone set) . By 
extension, a data set automatically answering on 
a public switched system is said to go "off 
hook. " 

On-line System 

A data communications system associated with a 
computer which processes data as it is received 
by the computer. 


Open System Interaction (OSI) 

Layered data communication model, or 
architecture, developed by the International 
Standards Organization. 

Operating System/Virtual Storage 2 (0S/VS2) 

A compatible extension of the IBM System 360 
Operating System that supports relocation 
hardware and the extended control facilities 
of System/370. 

OS Disk Operating System/Virtual Storage 
Extended (OS/ DOS/VSE) 

Partitioned Emulation Program (PEP) 

Packet Assembler /Disassembler (PAD) 

A software module that receives characters 
from terminals, assembles them into packets 
and sends them down the line. The receiving 
end disassembles the packets and sends the 
characters to the terminal. 

Packet Switching 

A data transmission technique in which a long 
message is broken into smaller units called 
packets. These packets can be individually 
addressed and routed throughout the network 
using several different routes. The receiving 
end node ascertains that all packets are 
received and in the proper sequence before 
forwarding the complete message to the 


A constant state or equal value. Parity 
checking is one of the oldest error checking 
techniques. Character bit patterns are forced 
into parity (total number of one bit odd or 
even) by appropriately adding a one or zero 
bit as appropriate, as they are transmitted; 
the parity (odd or even) is then verified upon 
receipt by the receiving device. 

Parity Bit 

A check bit appended to an array of binary 
digits, to make the sum of all the binary 
digits, including the check bit, always off 
or always even. 

Phase Shift Keying (PSK) 

A method of modulation that uses the differences 
in phase angle to indicate a certain bit or 
dibit. A reference oscillator determines the 
phase angle change of the incoming signal, which 
in turn determines which bit or dibit is being 

Point -to -Point 

Pertaining or referring to a communications line 
where exactly two stations are connected. 
Contrast with multipoint. 


A procedure which asks a terminal on a network 
if there is any information to transmit; 
usually done on a multipoint line. 

Private Automatic Branch Exchange (PABX) 

An automatic switchboard for handling large 
concentrations of telephones (extensions) . 
Synonymous with PBX. 

Professional Office System (PROFS) 

A IBM VM based product that supports the func- 
tions of calendar management, electronic mail, 
project scheduling, and the execution of a 
variety of analysis tools. Its focus is the 
manager or the professional. 


A set of procedures for establishing and con- 
trolling transmissions. Examples include BSC 
and SDLC. 

Protocol Conversion 

The process of translating the protocol native 
to an end -user device (e.g., a terminal) into 
a different protocol (e.g., ASCII to BSC), 
allowing that end -user device to communicate 
with another device (e.g., a computer) with 
which it would otherwise by incompatible. 
Protocol conversion can be performed by a ded- 
icated device (a "protocol converter"), by a 
software package loaded onto an existing system, 
such as a general -purpose computer, front -end 
processor, or PBX system, or by a value-added 
network, such as Telenet. 

Pulse Modulation 

The modulation of the characteristics of a 
series of pulses in one of several ways to 
represent the information -bearing signal. 
Typical methods involve modifying the ampli- 
tude. (PAM) , width or duration (PDM) , or posi- 
tion (PPM) . The most common pulse modultation 
technique in telephone work is pulse code mod- 
ulation (PCM). In PCM, the information signals 
are sampled at regular intervals and a series of 
pulses in coded form are transmitted, represent- 
ing the amplitude of the information signal at 
that time. 

Public Data Network (PDN) 

A networking service which fulfills all com- 
munication needs between the host computer and 
other processors and terminals. 


Physical Unit (PU) 


Quadrature Amplitude Modulation (QAM) 

16 level encoded Amplitude Modulation. Speed is 
usually 9,600 to 14,400 BPS. 

Real Time 

Pertains to a computer application whose 
response is a time frame almost simultaneous 
or within milliseconds of the actual event. 


A physical and electrical interface between 
computers, terminals, modems, and communications 
lines. A recommended standard developed by the 
Electronics Industries Association. 

RS-422 and RS-423 

Recommended Standards published by the Elec- 
tronic Industries Association establishing the 
interface requirements between modems and ter- 
minals or computers. 

Remote Job Entry (RJE) 

An HP software program which allows you to sub- 
mit jobs grouped together. Also called batch 

Serial Transmission 

The transmission of a character or byte of data 
one bit at a time. Contrast with parallel. 


(1) The engaging of two end -user processes 
in a logical connection. (2) Layer 5 of the 
International Standards Organization (ISO) Open 
Systems Interconnection (OSI) reference model for 
network architectures. 

Signal -to -Noise Ratio 

The relative power of signal to the noise on a 
line. As the ratio decreases, it becomes more 
difficult to distinguish between information and 


Pertaining to the capability to transmit in one 
direction only. Contrast with half -duplex and 
full -duplex. 

Single -wire Line 

A transmission line that uses the ground as one 
side of the circuit. 

Smart Terminal 

A terminal that can input data, receive results, 
and be preprogrammed 

(1) An impulse which, in a neutral circuit, 
causes the loop to open or causes absence of 
signal, while in a polar circuit it causes the 
loop current to flow in a direction opposite 
to that for a mark impulse. A space impulse is 
equivalent to a binary 0. (2) In some codes, 
a character which causes a printer to leave a 
character width with no printed symbol. 


A network topology in which each station is 
connected only to a central station by a 
point-to-point link, and communicates with all 
other stations through the central station. 

Start Bit 

In asynchronous transmission, a signal used to 
signify the beginning of the transmission of a 

Stop Bit 

In asynchronous transmission, the quiescent 
state following the transmission of a character; 
usually required to be at least 1, 1.42, 1.5 or 
2 bit times long. 

Switch Hook 

A switch on a telephone set, associated with the 
structure supporting the receiver or handset. 
It is operated by the removal or replacement of 
the receiver or handset on the support. 

Switched Line 

One of a series of lines that can be inter- 
connected through a switching center; a line on 
the public telephone network. Contrast with 
"leased line". 


Having a constant time interval between suc- 
cessive bits, characters, or events. Synchronous 
transmission uses no redundant information (such 
as the start and stop bits in asynchronous 
transmission) to identify the beginning and end 
of characters, and thus is faster and more effi- 
cient than asynchronous transmission. The 
timing achieved by transmitting sync characters 
prior to data; usually, synchronization can be 
achieved in two or three characters times. 


Synchronous Communications Binary 


A set of operating procedures for synchronous 
transmission used in IBM teleprocessing net- 
works. With BISYNC, some system batch terminals 
automatically perform error checking on all 
incoming data and request retransmission of a 
message whenever it is not received exactly as 
sent. As a transmitting terminal, the system 
automatically retransmits messages when they are 
not accurately received by the remote station. 
Because of the reliability of data transmissions 
using binary synchronous methods, it becomes 
economical to collect and store large amounts of 
data at the processor using either cassettes or 
a mass memory subsystem and to later transmit 
the data to computers or terminals, including 
other systems. 

Synchronous Data Link Control (SDLC) 

An IBM communications line discipline or proto- 
col associated with SNA. In contrast to BSC, 
SDLC provides for full -duplex transmissions and 
is more efficient. 

Synchronous Transmission 

A mode of data communcations by which the bit 
stream and character stream are slaved to 
accurately synchronized clocks at the receiving 
and transmitting stations. Start and stop 
pulses are not required with each character. 


An organized collection of parts or pro- 
cedures united by regulated interaction and 
interconnected to perform a function. 

Systems Network Architecture (SNA) 

The total description of the logical structure, 
formats, protocols, and operational sequences 
for transmitting information units through the 
communication system. Communication system 
functions are separated into three discrete 
areas; the application layer, the function 
management layer, and the transmission subsystem 
layer. The structure of SNA allows the ultimate 
origins and destinations of information- -that 
is, the end users- -to be independent of, and 
unaffected by, the specific communication -system 
services and facilities used for information 

System Generation (SYSGEN) 

The process of using an operating system to 
assemble and link together all of the parts 
that constitute another operating system. 

The published rate for a specific unit of equip- 
ment, facility, or type of service provided by a 
communications common carrier. Also the vehicle 
by which the regulating agencies approve or 
disapprove such facilities or services. Thus 
the tariff becomes a contract between customer 
and common carrier. 


Transmission of electrical signals over long 
distances, such as by radio, telegraph or 
telephone lines. 


A communications system combining two tech- 
nologies, data processing and telecommu- 
nications. Originally, an IBM trademark. 


A generic name for the international network of 
teleprinter subscriber services. Western Union 
provides such services within the U.S. and 
abroad under its Telex and Telex II trademarks. 
International record carriers (IRC'S) are now 
permitted to extend their telex services to the 
domestic U.S. 


Hardware device connected to a computer, used 
for inputting and receiving data. See Dumb 
Terminal, Smart Terminal, Intelligent Terminal. 

Time Sharing Option (TSO) 

A full -function time sharing system that 
provides interactive computing for the large 
system environment. It is an integral part of 


A transmission mode in which control character 
recognition is "suspended", allowing any bit 
pattern to be transmitted without unexpected 
results. The rules for control code recognition 
are changed so that commands involving specific 
operations, for example, Escape sequences, are 
not acted upon, but simply transmitted as data. 
Even in transparency mode, certain commands 
remain active; otherwise, once in transparency 
mode, there would be no way to get out of it. 

Token Passing 

A local area network access technique in which 
participating stations circulatea special bit 
pattern (the token) that grants access to the 
network to each station in sequence, often used 
in networks with a ring topology. 



The logical or physical arrangement of stations 
on a network in relation to one another. See 
ring and star. 

Touch - Tone 

An AT&T trademark for tone signaling equipment, 
which is superseding rotary dial equipment. Use 
of tones simplifies the switching system design 
and greatly expands the potential for adding 
features to telephone systems. It also speeds 
up the dialing operation for a person making 
a call. 

Two -wire channel 

A circuit containing a single wire pair (or 
logical equivalent) for non- simultaneous (i.e., 
half -duplex) two-way transmission. 

Teletypewriter Exchange Service (TWX) 

A switched teletypewriter service in which 
suitably arranged teletypewriter stations are 
provided with lines to a central office for 
access to other such stations throughout the 
U.S. and Canada. 

Value Added Network (VAN) 

A common carrier service which has been upgraded 
by a communication service. 

Virtual Storage (VS) 

The national storage space that may be regarded 
as addressable main storage by the user of a 
computer system in which virtual addresses are 
mapped into real addresses. The size of virtual 
storage is limited by the addressing scheme of 
the computing system and by the amount of 
auxiliary storage available, and not by the 
actual number of main storage locations. 

Virtual Storage Access Method (VSAM) 

An access method for direct or sequential 
processing of fixed and variable -length records 
on direct access devices. The records in a VSAM 
data set or file can be organized in logical 
sequence by a key field (key sequence) , in the 
physicalsequence in which they are written on 
the data set or file (entry - sequence) , orby 
relative -record number. 

Virtual Telecommunications Access Method /Network 
Control Program (VTAM/NCP) 

A set of programs that control communication 
between terminals and application programs 
running under DOX/VS, 0S/VS1, AND 0S/VS2. 

Voice -grade Channel 

A channel with bandwidth equivalent to a 
telephone line obtained through the public 
telephone network. The maximum potential 
bandwidth of a voice -grade channel is approx- 
imately 20K hertz; however, most voice -grade 
channels in a transmission facility are usually 
spaced 4000 Hz apart, and not all of the band- 
width is generally available to a user due to 
the presence of noise -limiting loading coils; 
the telephone network itself is usually defined 
in terms of channels with frequencies of from 
300 Hz to 3400 Hz. 


300 bps duplex modem standard for use on the 
general switched network 


1200 bps duplex modem standard for use on the 
general switched telephone network 
and on leased circuits. 


600/1200 bps modem standard for use on the 
general switch network 

V.24 CCITT equivalent to EIA RS-232C standard 
Wideband channel 

Referring or pertaining to an analog circuit 
that provides more bandwidth than a voice -grade 
telephone line, i.e., a circuit that operates 
at a frequency of 20K Hz or greater. Wideband 
(also known as broadband) channels are used for 
high-speed voice and data communications, radio 
and television broadcasting, some local area 
data networks, and many other services. 


An intelligent terminal. 

Packet Assembly/Disassembly facility (PAD) in a 
public data network 


Interface between DTE and DCE equipment for 
synchronous operation on public data networks. 


A protocol developed by CCITT, the standards 
writing organization for international tele- 
phone carriers, for packet swtiching procedures 
(governing the exchange of data units between 
the public data network and the user) . 


IBM by the Numbers 

Series 1 Minicomputer Model 495X, 32K-512K, 

System 23 Datamaster / 8086 Microprocessor 64K-128K 

System/ 34 

General purpose minicomputer system for all types 
of smaller businesses. Uses the SSP operating 
system. Supports the 5250 Information Display 
System family of terminal and printers in local and 
remote environments. BSC or SDLC communications is 
supported. Supports programming in RPG II, COBOL, 
and BASIC. 

System/36 General Purpose minicomputer 
System/ 38 

Multi-user, general purpose SP sytem with a virtual 
design. Uses the CPF operating system. Supports 
the 5250 Information Display System family of 
terminals and printers in local and remote 
environments. Only SDLC data communications is 
supported. Supports programming in RPG and COBOL. 

360 Mainframe Computer 
370 Mainframe Computer 

Models 138, 148, 158, 168, 195 

XT/ 370 Mainframe in a micro box 68000 & 8088 

650 Discontinued Mainframe 

1401 Discontinued Mainframe 

1403 Printer 

1443 Printer 

2250 Display Unit 

2550 Single Cluster Feature 

2551 Dual Cluster Feature 

2704 Discontinued Front End Processor 
2770 Bisync batch workstation 
2780 Bisync batch workstation 

303X (1,2,3) Maniframe 

Full range of high performance processor for large 
system environements with 2-32 MB processor 
storage. 5 - 2 block multiplexor channels. 

308X (1,3,4) IBM's largest series of processors 

3178 Display Station Models CI, C2 - Less expensive 3278 

3179 Display Station - cheaper 3279 type color display 

3180 Display Station 

3203 Line Printer, up to 1200 1pm 

3211 Line Printer, up to 2000 1pm 

3230 Dot Matrix Printer, up to 350 cps 

3262 Line Printer, Model 1,5 - 650 1pm, Model -11 325 1pm 

3268 Printer 340 cps 

3270 PC - Communications Terminal & computer 

3271 Bisync cluster controller 

Device Control Unit - a controller for the 3270 
Information Display System family of displays and 
printers (type B devices) . 


1 - 480 -character buffer /BSC line control 

2 - 1920 -character buffer/BSC line control 

3 - 480-character buffer/SDLC line control 

4 - 1920 -character buffer/SDLC line control 


Remote cluster - up to 32 devices attachable 
Line speed up to 7200 bps for BSC (9600 via RPQ) 
Line speed up to 9600 bps for SDLC 

3272 Device Control Unit (type B devices) 


1 - 480-character buffer 

2 - 1920 -character buffer 


Local cluster - up to 32 devices attachable 
Data transfer to channel up to 650,000 bps 

3274 Models 21A, 21B, 21D, 31A, 41A, 41D (local) 

Floor standing Cluster Controller 

3274 51C, 61C Models A,B,C,D 

Model 51C - Features Attaches up to eight type A 
and four type B devices. Supports full range of 
3270 display and printer products. 

3275 Bisync workstation, terminal and printer 

3276 SNA cluster controller and terminal 

3276 Models 1, 2, 3, 4, BSC or SDLC 
Models 11, 12, 13, 14 SDLC protocol 

Control Unit Display Station 


1 - 960-character buffer/BSC 

11- 960-character buffer/SDLC 

2 - 1920 -character buffer/BSC 

12- 1920 -character buffer/SDLC 

3 - 2560 -character buffer/BSC 

13- 2560 -character buffer/SDLC 

4 - 3440 -character buffer/BSC 

14- 3440 -character buffer/SDLC 


Remote small cluster - up to 8 devices attached 
Lease line facility up to 7200 bps (BSC) or 9600 
bps (SDLC). Public switched network up to 4800 bps. 

3277 Batch Terminal 

3278 Display Station 



1 - 960-character buffer (12x80) 

2 -1920 -character buffer (24x80) 

3 -2560 -character buffer (32x80) 
4" -3340 -character buffer (43x80) 
5 -3564 -character buffer (27x132) 

Model 5 not attachable 


Attaches to 3274 and 3276. 
to 3274B or 3276. 

3279 Color Display Station 


2A - 1920 -character buffer (24x80) Four colors. 

3A - 2560 -character buffer (32x80) Four colors. 

2B - 1920 -character buffer (24x80) Seven colors. 

3B - 2560 -character buffer (32x80) Seven colors. 

3287 Printer 


1 - 80 cps, 132 print positions 

2 - 120 cps, 132 print positions 

11- 80 cps, 132 print positions 

12- 120 cps, 132 print positions 


Model 1 and 2 attachable to 3271, 3272, 3274, 3276, 

3289 Line Printer, up to 120 cps 

3290 Plasma Display Information Panel 
3299 Multiplexer 

3330 Disk Storage Unit 
3333 Disk Storage Unit 
3370 Disk Storage Unit 
3375 Disk Storage Unit 
3540 Diskette Input/Output Unit 

3600 Banking System 

3601 Finance Controller 
3650 Retail System 
3660 Supermarket System 
3694 Document Processor 
3701 EIA/CCITT Interface 

Communications Controller. Withdrawn from 
production in August 1978. Contains 64K bytes of 
storage and can handle up to 34 half -duplex lines. 


Communications controller that provides for the 
physical management of the communcatons network. 
It can be locally attached or can operate as a 
remote communications controller. The 3705 has a 
maximum storage capacity of 512K memory which is 
used to store the control program and to buffer 
incoming and outgoing traffic. The control program 
can be NCP (Network Control Program) or EP 
(Emulation Program -270X emulation). Provides 
attachment facilities for asynchronous, binary 
synchronous (BSC) , and synchronous data link 
control (SDLC) protocols. 
Can handle up to 352 lines. 



Communications Controller 
Daisy Wheel Printer 
8" Diskette Format 

Batch /Cluster Controller /workstation 

Batch Terminal 

Programmable Terminal 

Printer Model 1 and 3 

Storage Control Unit Models 2 and 3 

Mass Storage Facility 

Storage Control Unit 

Model 1 (2400/1200 bps) modem 

Model 1 (4800/1200 bps) modem 

Model 1 and 2 (9600/4800 bps) modem 

Model 1 (2400/1200 bps) modem 

Minicomputer - Pre -configured entry -level 4300 
processor with 1MB processor storage. 
Display/Printer Adapter which permits attachment of 
3278 Model 2A or 3279 Model 2C plus up to 15 
additional A -type devices such as 3262 line 1C and 
2C, or 3289 line printers Model 4. 


Mid -size minicomputer processor with 1-4MB 
processor storage. One standard byte multiplexor 
channel. One standard block multiplexor channel 
which can support up to 128 devices. 
Console/printer adapter for up to 15 A- type 
printers/displays . 


High performance and high function 
System/ 370 -compatible 4300 processor with 2 -16MB 
processor storage. 2 block multiplexor channels. 
Console/printer adapter. 

4381 4-16 Megabytes, 12 I/O channels, air cooling 
4701 Finance Controller 

4962 Disk Storage Unit 

4963 Disk Subsystem 

4964 Diskette unit 

4969 Magnetic Tape Subsystem 

497X Printers 

497X Display Stations 

4987 Programmable Communications Subsystem 

5110 Desktop Computer 

5120 Desktop Computer 

5150 IBM PC 

5160 IBM PC XT 

5203 Printer Model 3 

5210 Daisy wheel printer 

5211 Line Printers up to 300 1pm 
5213 Printer 

5224 Printers Model 1 - 140 1pm, Model 2 - 240 1pm 

5225 Printers 

Model 1 - 280 1pm Model 2 - 400 1pm, 
Model 3 - 490 1pm Model 4 - 560 1pm 

5234 Time Entry Station 

5235 Data Entry Station 
5251 -11 Display Station 

5251 -12 Cluster Controller /display terminal 

5252 Dual Display Station 


5256 Printers 

Model 1- 40cps, Model 2- 80 cps, Model 3- 120 

5280 Distributed Data System 
530X Workstation Controller 
5500 Modem 1200 bps, Nonswitched 
550X Modem 1200 bps, Switched 
5520 Administrative System 
564X Modem 2400 bps 
574X Modem 4800 bps 

5798 -RHE System 38 Front End Processor - Software 
6670 Information Distributor 

7426 Terminal Interface Unit - Protocol Converter 

7850 Teletypewriter Adpater 

81XX Distributed processing computer series 


9000 Instrumentation System 68000 - Xenix 

Reading List - Synchronous Products 

ComputerWorld Newsweekly 
CW Communications 
Box 880 Cochituate Road 
Framingham, MA 01701 

Data Communications 

1221 Avenue of the Americas 
New York, NY 10020 

Data Decisions 
20 Brace Road 
Cherry Hill, NJ 08034 

Data Communications - a users guide 
Kenneth Sherman 
Reston 1981 

Data Communciations For Microcomputers 

Nichols, Nichols, Musson 
McGraw Hill 1982 

Data Communications Concepts. 
Fourth Edition (June 1982) 
GC21-5 169-3 

IBM Corporation, Information Development, 
Department 245, Rochester MN 55901. 

Fundamentals of Data Communications. 
Jerry FitzGerald & Tom S. Eason 
John Wiley & Sons 1978 

IBM System 38 Data Communications 
Programmer's Guide 
IBM Corporation 

Micros and Modems: 

Telecommunicating with Personal Computers 
Jack M. Nilles 
Reston Publishing 1983 

The Network Revolution 

Confessions of a Computer Scientist 

Jacques Vallee 

And/Or Press, Inc. 1982 

RS-232 Made Easy 

Martin Sayer 

Prentice Hall, Inc. 1984 

Systems Network Architecture 
General Information Manual 
IBM Corporation 

Systems Network Architecture 
Reference Summary 
IBM Corporation 

The RS-232 Solution 
Joe Campbell 

Sybex Computer Books. 1984 

Telecommunications and the Computer 
James Martin 
Prentice-Hall, Inc. 1969 

Introduction to the IBM 3270 Information 
Display System Manual 
IBM Corporation 



Ripple computer 

20525 Mariani Avenue 
Cupertino, California 95014 
(408) 996-1010 
TLX: 171-576