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Micro-to-Mainframe Links Are Forged by Stream of Products.

Increasingly, users of IBM (International Business Machines Corporation, Armonk, NY, The world's largest computer company. IBM's product lines include the S/390 mainframes (zSeries), AS/400 midrange business systems (iSeries), RS/6000 workstations and servers (pSeries), Intel-based servers (xSeries)  and other popular personal computers are looking for Looking for

In the context of general equities, this describing a buy interest in which a dealer is asked to offer stock, often involving a capital commitment. Antithesis of in touch with.
 ways to communicate with mainframe computers, either to access centralized data files or to utilize powerful host resources such as high-speed print facilities. To satisfy this mushrooming demand, more than 400 firms have already come up with a variety of hardware and software products, making micro-to-mainframe communications one of the fastest-growing segments of the computer industry. According to according to
1. As stated or indicated by; on the authority of: according to historians.

2. In keeping with: according to instructions.

 International Resource Development of Norwalk, Connecticut, the market exploded from $50 million in 1982 to an estimated $500 million in 1984. Another research firm, Input of Palo Alto, California “Palo Alto” redirects here. For other uses, see Palo Alto (disambiguation).
Palo Alto (IPA: /ˌpæloʊˈʔæltoʊ/, from Spanish: palo: "stick" and alto: "high", i.e.
, projects that by 1988, almost a quarter of all computer operations in larger corporations will involve micro-to-mainframe links.

Micro-to-mainframe products range from protocol converters and emulators for IBM, Digital and other popular terminals, to sophisticated software that allows PC users to move data back and forth between micro and mainframe without compromising system security or data base integrity.

The simplest way to link micros with mainframes would be to use an asynchronous Refers to events that are not synchronized, or coordinated, in time. The following are considered asynchronous operations. The interval between transmitting A and B is not the same as between B and C. The ability to initiate a transmission at either end.  interface on the micro and connect to a front-end processor front-end processor - (FEP) 1. A small computer necessary to enable an IBM mainframe using SNA to communicate beyond the limits of the dinosaur pen.

2. A small computer controlling the screen and keyboard of a Symbolics 3600 LISP Machine.
 as an ASCII ASCII or American Standard Code for Information Interchange, a set of codes used to represent letters, numbers, a few symbols, and control characters. Originally designed for teletype operations, it has found wide application in computers.  device. Despite its simplicity, this approach may not be the most economica. Most micros come with an asynchronous interface, but users need to figure in the cost of lines and modems for each unit, not to mention typing up the processor ports. Asynchronous communications is also limited by the lack of error control and its poor efficiency for transferring files. Typical data rates of 2.4 kb/s or less reduce still further the link throughput. In addition, applications in the mainframe may not work with ASCII devices, so expensive conversion software may have to be installed in the mainframe.

A more cost-effecctive approach is to connect multiple micros to a protocol converter that communicates with the host over a synchronous link. Typically, such converters translate the code from ASCII to EBCDIC (Extended Binary Coded Decimal Interchange Code) Pronounced "eb-suh-dick." The binary code for text as well as communications and printer control from IBM.  and the protocol from asynchronous to bisynchronous or SDLC (Synchronous Data Link Control) The primary data link protocol used in IBM's SNA networks. It is a bit-oriented synchronous protocol that is a subset of the HDLC protocol. See SNA, DLC and Microsoft DLC.

. Besides permitting higher data rates and more efficient and accurate data transfer, the protocol converters give the micro users access to host applications written for 3270-type terminals. Remote dial-up access hot Dial-up access is a form of Internet access via telephone line. The client uses a modem connected to a computer and a telephone line to dial into an Internet service provider's (ISP) node to establish a modem-to-modem link, which is then routed to the Internet.  to the protocol converter from portable computers also allows occasional users to gain access to host computer programs and resources.

Another way to equip micros for bisync operation is to install a communications adapter board in the micro along with 3270 emulation software. In both cases, the user is limited by the ASCII keyboard, which differs considerably from the 3270 and has fewer keys, so that multi-key sequences must be used for some functions.

Some suppliers provide circuit boards that convert micros into 3278 or 3279 terminals, which connect to the 3274 controller via conventional coaxial cable links. While this approach does not overcome the limitation of the ASCII keyboard, it most closely maps existing 3270 operations and requires minimal changes.

Protocol converters Target IBM

Most suppliers of protocol converters target IBM mainframes Following are the mainframe architectures used in IBM mainframes since the original System/360 introduced in 1964.

Year Architecture Model numbers System/360 1964 System/360 2xxx (2020 to 2195) System/370
, which are reported to account for 70 percent of installed systems. Timeplex of Woodcliff Lake, New Jersey Woodcliff Lake is a borough in Bergen County, New Jersey, United States. As of the United States 2000 Census, the borough population was 5,745.

Woodcliff Lake is also the name of the reservoir that lies primarily within the town--a small part of it lies in neighboring
 calls its family of protocol converters "Tru-Blu." The Tru-Blu 78 allows a standard asynchronous ASCII terminal A simple input/output device that transmits and receives ASCII data. See dumb terminal.  to substitute for a synchronous 3278 terminal in SNA (Systems Network Architecture) IBM's mainframe network standards introduced in 1974. Originally a centralized architecture with a host computer controlling many terminals, enhancements, such as APPN and APPC (LU 6.  networks. The companion Tru-Blu 74 substitutes for a 3274 terminal cluster controller A control unit that manages several peripheral devices, such as terminals or disk drives.

, able to accommodate up to nine ASCII terminals, while the Tru-Blu 80 allows an asynchronous ASCII terminal and printer to perform the same functions as a 3780 RJE (Remote Job Entry) Transmitting batches of transactions from a remote terminal or computer. The receiving computer processes the data and may transmit the results back to the RJE site for printing.  workstation. Rounding out the family, the Tru-Blu 87 performs the protocol conversions needed to match the IBM type A coax adapter See 3270 emulator.  of the 3274 cluster controller to a printer.

Halcyon hal·cy·on  
1. A kingfisher, especially one of the genus Halcyon.

2. A fabled bird, identified with the kingfisher, that was supposed to have had the power to calm the wind and the waves while it nested on the sea
 of San Jose, California San Jose (IPA: /ˌsænhoʊˈzeɪ/) is the third-largest city in California, and the tenth-largest in the United States. It is the county seat of Santa Clara County.  claims to have been the first to introduce a multi-function protocol processor with its Model 3703, which allows users to incorporate a variety of non-SNA terminals into an existing SNA network. The 3703 may be configured with up to 12 ports, any of which is capable of interconnecting a different kinds of ASCII and/or bisync device, with all devices communicating with the host over a single SDLC link.

Micom's new 16-channel Micro7400 protocol converter emulates all standard IBM 3270 functions, allowing personal computers and asynchronous ASCII terminals to access IBM mainframes as 3270-class devices for a price of less than $355 per channel. As the smaller members of the Micro7400 family, the 16-channel model appears to the host computer as an IBM 3274 Model 61C cluster controller communicating in either bisync or SDLC protocol. Attached asynchronous devices can functions as IBM 3278 display stations, 3279 color display stations or 3287 printers. Special support is provided to allow printing terminals to interact with programs originally developed for display terminals.

In addition to full 3270 emulation, Micro7400s offer a number of enhancements to the 3270 environment, according to the Chatsworth, California firm. Extended capabilities include automatic log-on, inbound priority levels, banner and broadcast messages, and security features such as password protection and several powerful automatic log-off options. With the Micro7400s, you can also switch between two IBM host computers or between an IBM host and up to eight asynchronous computer ports.

Another feature of the Micro7400 is its Command Port, a password-protected terminal interface separate from the 16 channel interfaces, which allows an operator to alter operating parameters such as priority assignments, and also provides monitoring, diagnostic and control facilities. The Command Port is augmented by two special features: TACT (Terminal-Activated Channel Test) for do-it-yourself troubleshooting from the user's terminal and TICC TICC Terlingua International Chili Championship (Texas)
TICC Topics in Clinical Chiropractic
TICC Terminal Initiated Channel Configuration
TICC Tactical Information Communication Center
 (Terminal-Initiated Channel Configuration) for setting and altering terminal-related operating parameters such as parity.

The 16-channel converter sells for $5,650 and is available with matched integral modems operating at 2.4, 4.8 and 9.6 kb/s. In addition, Micom offers specialized software for the IBM Personal Computer
''This article discusses to the original IBM PC. For IBM-like PCs in general ("clones"), see IBM PC compatible.

? IBM 5120 IBM PC Series IBM Personal Computer XT • IBM Portable Personal Computer • IBM PCjr ?

 that allows it to fully exploit the capabilities of the Micro 7400 when accessing a mainframe.

Reduces Overhead

Paradyne's 9403 protocol converters allow users to add a wide variety of micros and other low-cost asynchronous devices to systems incorporating the Largo, Florida Largo is the third largest city in Pinellas County, Florida, USA and is part of the Tampa Bay Area. Centrally located, it is the crossroads of the county. As of the 2000 census, the City had a total population of 69,371. As of 2004, the population recorded by the U.S.  firm's Pixnet communications network The transmission channels interconnecting all client and server stations as well as all supporting hardware and software. . Pixnet eliminates traditional tele-processing overhead by making remote devices appear as local devices to the host. The 9403 protocol converters permit asynchronous devices to appear as local 3277 devices by communicating in Pixnet's 9476 protocol at rates from 2.4 to 9.6 Kb/s. System flexibility is enhanced sinced terminals can be identified by type at the time of connection, eliminating the need for dedicated ports. Terminals can be located remotely, using leased or dial-up lines, and operated in conjunction with multiplexers. Model 9403-01 has a Pixnet line four ports and is priced at $4900; the eight-port model 9403-02 sells for $5900.

Case Rixon Communications of Silver Spring, Maryland Not to be confused with Silver Springs.
Silver Spring is an urbanized, unincorporated area in Montgomery County, Maryland, USA. After Baltimore and Columbia, Silver Spring is the third most populous Census Designated Place in Maryland.
 also includes an asyncto-bisync protocol converter in its new 81X Openline communications processor family. The 81X features a single card unit with 10 I/O ports configured by Program Option Packages, or Pop-Pacs. Resembling an eight-track tape cartridge See cartridge.  that plugs into the basic 81X unit, the Pop-Pac contains the configuration software to define the desktop communications processor's function.

Other suppliers of protocol converters include Protocol Computers, Incorporated of Woodland Hills, California; Icot Corporation of Mountain View, California For the census-designated place, see Mountain View, Contra Costa County, California. For other places called "Mountain View", see .
Mountain View is a city in Santa Clara County, in the U.S. state of California. The city gets its name from the views of the Santa Cruz Mountains.
; and Gandalf Data of Wheeling, Illinois Wheeling is a village in Cook County, Illinois, United States. The population was 34,496 at the 2000 census, and estimated to be 36,641 as of 2005. Geography
Wheeling is located at  (42.131526, -87.
. Racal-Telesystems also supplies protocol converters, but they are used mainly to permit communications between incompatible word processors. (Details of these protocol converters and similar devices for use with word processors will appear in the "Datacomm Update" on office automation in the June 1985 issue of Communications News.)

Coax Connections Copy 3270

Digital Communications Transmitting text, voice and video in binary form. See communications.  Associates Claims to have introduced the first micro-to-mainframe coaxial interface with its Irma board The first 3270 emulator for PCs. Introduced in 1982, it was the first product to provide PC to IBM host connectivity. Irma was originally spelled all caps (IRMA) and was developed by Digital Communications Associates (DCA), which later merged with and became part of Attachmate Corporation. . More than 80,000 Irma units have been installed since the product was introduced in December 1982. "Micro-to-mainframe communications is an extremely important part of our business," says Bert Nordin, president and chief executive officer of the Norcross, Georgia Norcross is a city in Gwinnett County, Georgia, United States. The city had a population of 8,410 in 2000. Census Estimates for 2005 show a population of 9,887. History
Norcross was founded in 1866 by John Thrasher.
 firm. Nordin sees a major trend towards using the distributed processing The first term used to describe the distribution of multiple computers throughout an organization in contrast to a centralized system. It started with the first minicomputers. Today, distributed processing is called "distributed computing." See also client/server.  power of the micro-to-mainframe connection, particularly in the area of file transfer. "File transfer software has become extremely important since data must be consolidated and moved to the mainframe if it is to be used by more than one person," he notes.

Waverly Graham, executive vice president, also believes there's a bright future for micro-to-mainframe communications. "The micro-to-mainframe link will remain a part of the office environment at least until some unforeseen time when microcomputers have so much storage, and are linked together in such a away, that each can have a duplicate copy of the master data base that resides on the mainframe," he says. "But that time may never come."

As a coaxial interface, Irma is intended to give 3278/79 terminal capabilities to IBM PCs and compatibles located at IBM 3270 terminal controller sites. For PCs located away from terminal controller sites, DCA (1) (Document Content Architecture) IBM file formats for text documents. DCA/RFT (Revisable-Form Text) is the primary format and can be edited. DCA/FFT (Final-Form Text) has been formatted for a particular output device and cannot be changed.  offers Irmaline, which provides the PCs with 3278 terminal capabilities and remote access to the controller coax ports. Also, Irmaline works with personal computers and asynchronous terminals that are not IBM-compatible. Another product, Irmalette, combines with Irmaline to deliver Irma's software power to the remote IBM PCs or compatibles. For applications where no 3270 terminal controller port is available, or where the PC-attached printer must serve as a network printer, the firm offers a series of products called Irmacom, which let the PC act as an IBM 3274 or 3276 controller or as a 3770, 2780 or 3780 RJE workstation.

Rounding out the Irma family are the Irmaprint, which provides 3287 emulation and connection to 3270 controller coax ports for non-IBM printers; Irmalink software, which permits file transfer between PCs and IBM mainframes under TSO (Time Sharing Option) Software that provides interactive communications for IBM's MVS operating system. It allows a user or programmer to launch an application from a terminal and interactively work with it. The TSO counterpart in VM is called CMS.  and CICS (Customer Information Control System) A TP monitor from IBM that was originally developed to provide transaction processing for IBM mainframes. It controls the interaction between applications and users and lets programmers develop screen displays without ; and Irmakey/3270, which provides 3270 and IBM PC keys on one keyboard in their usual locations. In addition, Irmakey allows the function of any key to be redefined to perform multi-key operations with a single keystroke key·stroke  
A stroke of a key, as on a word processor.


In December, DCA adapted Irma to bring its emulation and file-transfer capabilities to the IBM PC-AT PC-AT Personal Computer, Advanced Technology . Irma now allows an IBM PC-AT to emulate an IBM 3278/79 terminal and to transfer data to and from a mainframe while retaining its stand-alone computing powers. This allows the AT user to communicate with and extract data from a mainframe while using software resident in the AT. Irma also brings to the AT user a host of software programs written by third-party software developers with Irma in mind.

One such product is the ForteGraph from Forte Data Systems, which provides mainframe graphics capabilities to IBM personal computers using the IRMA 3278/79 terminal emulator See terminal emulation.

(communications) terminal emulator - A program that allows a computer to act like a (particular brand of) terminal, e.g. a vt-100. The computer thus appears as a terminal to the host computer and accepts the same escape sequences for functions such
. ForteGraph allows a PC or compatible to act as a full-function IBM color graphics The ability to display graphic images in colors.  terminal linked to an IBM mainframe IBM mainframes, though perceived as synonymous with mainframe computers in general due to their marketshare, are now technically and specifically IBM's line of business computers that can all trace their design evolution to the IBM System/360.  computer. The product sells for $1,595.

Forte Data Systems was also among the first to offer an emulator package for the IBM PC-AT for communications with an IBM mainframe computer. With Forte-PJ, the AT user can easily "toggle To alternate back and forth between two states.

toggle - To change a bit from whatever state it is in to the other state; to change from 1 to 0 or from 0 to 1. This comes from "toggle switches", such as standard light switches, though the word "toggle" actually refers to
" back and forth between stand-alone (DOS) mode and a session with a mainframe. Concurrent DOS An early multiuser DOS-compatible operating system from Digital Research. See Multiuser DOS.  and mainframe sessions can be supported through the use of the Desq windowing For Northcoast
Where we call someone over and then roll our window up on them. Bassline preference.

For Example: "Hey, Andi." *insert window being rolled up* "HAHAHA.
 package from Quarter-deck. The Forte-PJ package sells for $1,195.

The San Jose, California firm also allows IBM PC users to move up to the functionality of an IBM 3270-PC advanced workstation through a package called the Forte 3270 PC. With the package, PC users can obtain data from multiple host applications and view the data in concurrent sessions while maintaining the processing power of the PC.

"IBM introduced the 3270-PC to give office and technical users the ability to interact with the host computer and, at the same time, be able to perform programming tasks at their desks," says James Ottinger, Forte president. "By installing the Forte 3270 PC, users can achieve the same results without having to replace their equipment."

As with the 3270-PC, the Forte package provides advanced windowing techniques so that users can view up to seven interactive sessions on their screens, including four active host sessions and one PC-DOS The DOS operating system originally developed by Microsoft and supplied by IBM on its PCs before Windows 95 became the norm. Up until DOS 6, PC-DOS was almost identical to Microsoft's MS-DOS for non-IBM PCs, and both versions are called "DOS." See "IBM's DOS 6" under DOS 6.  session. Two remaining windows are available for notepad The text editor that comes with Windows. It is a very elementary utility, but gets the job done most of the time. See text editor and WordPad.

(text, tool) Notepad - The very basic text editor supplied with Microsoft Windows.
 sessions, handy for personal remainders or for copying data from any of the host windows. Window size and location can be adjusted, or individual windows can be enlarged to full screen. Up to 10 different screen layouts can be saved on disk for later recall. In addition, host data can be copied to a 3274-attached printer, and screen copy from the host sent to a PC printer or captured on a disk. The package sells for $1,495.

Bubble Taps Host Resources

In a departure from traditional micro-to-mainframe links, Forte recently introduced a host-based software "environment" that enables IBM PC users to access host facilities and files through the same, familiar PC-DOS commands used to call up locally stored data. EcomNet (Extended Communications Network) allows PC users to regard the host as an easy-to-access resource, while at the same time gives a company's MIS department a high degree of control over that access.

EcomNet functions as a PC-DOS "Bubble" around the mainframe. PC users can access host files, mass storage and high-speed print facilities with nothing more than PC-DOS commands already familiar to them. There are no complicated mainframe commands or procedures to learn. EcomNet handles all that, even including log-on, transparently to the user.

"What results is a star network, using the mainframe as a file server," explains Ottinger. "It's an 'environment' approach to connectivity, as opposed to a terminal emulation Using software in a desktop machine to make it perform like a hardware terminal. The emulated terminal is typically in the VT100-500 family, designed originally by Digital Equipment.  or program-to-program approach." He claims EcomNet is more flexible than program-to-program links, in that it acts as a data highway to any host file, defined for access by the MIS department.

EcomNet will run on Most IBM mainframe computers. PCs connect via coaxial cable through 3270-type control units. They need to be equipped with either Forte PJ or the PC 78-2 package and have at least 128K of random access memory. Forte says that it will continue to add features to EcomNet in the coming months, such as electronic mail capabilities and Pc-initiated batch processing (1) Performing a particular operation automatically on a group of files all at once rather than manually opening, editing and saving one file at a time. For example, graphics software that converts a selection of images from one format to another would be a batch processing utility. .

PC/Com software from Mom Corporation, in Atlanta also works with Irma to link an IBM PC or compatible computer with an IBM mainframe running CICS, CMS (1) See content management system and color management system.

(2) (Conversational Monitor System) Software that provides interactive communications for IBM's VM operating system.
 or TSO facilities. PC/Com has file-management capabilities that allow the user to manage mainframe and micro files interchangeably. It has the facility for creating and deleting files; editing data within a file; and renaming, copying, displaying and/or printing files. Files can be stored on either computer for subsequent processing. The host communications interface also provides user-defined passwords and supports existing host-level password and user-identification security procedures. The mainframe module of PC/Com allows the data processing data processing or information processing, operations (e.g., handling, merging, sorting, and computing) performed upon data in accordance with strictly defined procedures, such as recording and summarizing the financial transactions of a  manager to maintain centralized control 1. In air defense, the control mode whereby a higher echelon makes direct target assignments to fire units. 2. In joint air operations, placing within one commander the responsibility and authority for planning, directing, and coordinating a military operation or group/category of  of all files stored on the mainframe.

The interface costs $400 for a mainframe using CMS or TSO, $2,000 for CICS, and $395 for each personal computer connected. Recently, the firm, which is a division of National Product Marketing, redesigned PC/Com to work with other popular printed-circuit boards that emulate 3270 terminals as well as SDLC and bisync terminal controllers, including boards from Forte and Quadram.

Another industry pioneer is Techland Systems of New York City New York City: see New York, city.
New York City

City (pop., 2000: 8,008,278), southeastern New York, at the mouth of the Hudson River. The largest city in the U.S.
, whose Blue Lynx 3270 Remote was among the first micro-to-mainframe links introduced. Last November, the firm enhanced its 3270 SDLC emulation package to support five logical units and to provide multiple windowing capability with the ability to hotkey from session to session. The package consists of circuit boards and disks that come bundled with Techland emulation software and the firm's 3270 keyboard. With the package, PC users can cross-reference two mainframe files on a single screen, hotkey from mainframe session to PC applications, then toggle back to the same place on the mainframe session, or run a single DOS session concurrently with a 3270 session.

Techland has also added data security features for both dial-up and stand-alone uses of PCs, based on the NBS (National Bureau of Standards) See NIST.

NBS - National Bureau of Standards: part of the US Department of Commerce, now NIST.
 data encryption standard See DES.

Data Encryption Standard - (DES) The NBS's popular, standard encryption algorithm. It is a product cipher that operates on 64-bit blocks of data, using a 56-bit key. It is defined in FIPS 46-1 (1988) (which supersedes FIPS 46 (1977)).
. For dial-up applications, the product supports IBM SDLC protocols and provides exact emulation of IBM's Cryptographic Feature 3680. For stand-alone applications, it limits the use of confidential applications, corporate data and spreadsheets to specific authorized users on specific PCs.

Links Tie LANs to Mainframes

One aspect of micro-to-mainframe communications that is generating considerable interest is the link between mainframe and local-area network. "The inability of LANs to communicate with the mainframe has been a restraining factor in the minds of corporate decision-makers considering LANs," says Harris Landgarten, Techland president. His firm addresses this concern with a product called the BlueLynx Gateway, which allows one PC on a local-area network to act as an IBM 3274 and communicate synchronously through a single modem and telephone line. Other PCs on the LAN (Local Area Network) A communications network that serves users within a confined geographical area. The "clients" are the user's workstations typically running Windows, although Mac and Linux clients are also used.  use the first PC as a gateway to access mainframe data by emulating 3278/3279 remote terminals with 3287 printers.

Up to 32 supported mainframe sessions can be distributed to other PCs in the LAN. Also, more than one Gateway can be supported on the LAN, expanding access to more than one host or more than 32 mainframe sessions. According to Landgarten, the BlueLynx Gateway is compatible with virtually every major LAN. In a typical configuration designed to support an eight-PC network, the gateway costs $2,000.

Pathway Design has one of the most complete micro-to-mainframe offerings. Its product families permit IBM and compatible personal computers to communicate with a variety of IBM mainframes in both MS-DOS MS-DOS
 in full Microsoft Disk Operating System

Operating system for personal computers. MS-DOS was based on DOS, developed in 1980 by Seattle Computer Products. Microsoft Corp. bought the rights to DOS in 1981, and released MS-DOS with IBM's PC that year.
 and LAN environments, and also support multi-user systems operating under Unix. Each product family offers "value-added" emulation of commonly supported 3270, 3770, 3780 and 2780 devices.

Unix Connections

The uniPATH gateway family permits Unix-based supermicros to communicate with a variety of IBM mainframes in SNa and bisyne networking environments. The software is resident on the supermicro's hard disk and supports multiple, concurrent communications sessions for numerous devices connected to the Unix system Noun 1. UNIX system - trademark for a powerful operating system
UNIX, UNIX operating system

operating system, OS - (computer science) software that controls the execution of computer programs and may provide various services

The Wellesley, Massachusetts Wellesley is a town in Norfolk County, Massachusetts, United States. The population was 26,613 at the 2000 census. It is best known as the home of Wellesley College and Babson College.  firm's pcPATH and netPATH software operates in conjunction with a multi-function, dual-channel circuit card that plugs into a PC expansion slot A receptacle inside a computer or other electronic system that accepts a printed circuit board. The number of slots determines future expansion. See PC data buses.

(hardware) expansion slot - A connector in a computer into which an expansion card can be plugged.
 to permit communications with SDLC or bisync protocols over leased and switched lines, the pcPATH products allow a variety of IBM-compatible personal computers to communicate with IBM hosts in SNA and bisync networking environments; the netPATH products permit 32 concurrent host communications sessions for all nodes on several popular LANs. The netPATH software resides on a network gateway and operates with a number of LANs, including Corvus Systems' Omninent, 3Com's Etherlink and Orchid Technology's PCnet.

Pathway Design's SNA products support Physical Unit Type 2 with Logical Units 1, 2 and 3, an advanced implementation of IBM's architecture that Pathway President Robert Broggi claims is the most complete and versatile implementation of SNA communications services available on personal computers. With the multi-tasking design of the software, users can perform concurrent communications functions, maintain an SNA connection with the host while running a local application, initiate printing functions from the host for multiple PC printers, and expect a "graceful shutdown" without loss of data should an SNA connection become faulty. The firm's RJE products support host data compression data compression

Process of reducing the amount of data needed for storage or transmission of a given piece of information (text, graphics, video, sound, etc.), typically by use of encoding techniques.
, full-formatted printing and capabilities for translating ASCII or EBCDIC line transmission formats, allowing transfer directly to and from a hard or floppy disk.

Xerox has added communications features to its Ethernet LAN so that network users can exchange information with computer systems from other manufacturers, including IBM and Digital Equipment Corporation. 3Com of Mountain View, California is providing the direct hardware connection to Ethernet for the IBM PC. Protocol software, which allows the PC user to edit a document on the PC and then acces Ethernet network services for electronic printing, electronic filing, electronic mail and mainframe acces, is being jointly developed by 3Com and Xerox. For the IBM PC and other systems on the network, Xerox internetwork protocols make it possible to access machines not just on one local Ethernet network, but on Ethernet networks in the same building, across the country or around the world.

Xerox has also provided 3278 emulation for it 8010 Star professional workstation, providing compatibility with SNA protocols. A Star user can display as many as six 3278 'windows' and simultaneously access up to six different programs or mainframes using SNA. Xerox is also providing software to emulate a VT-100 terminal for communications with Digital computers. In addition, the firm is offering a remote batch See RJE.  computer service on the network for multi-vendor document interchange based on IBM 2770, 2780 and 3780 communications protocols.

To extend the reach of its Net/One local-area network, Ungermann-Bass of Santa Clara, California Santa Clara, California (IPA: /ˌsæntəˈklærə/) , founded in 1777 and incorporated in 1852, is a city in Santa Clara County, in the U.S. state of California.  has reached a multiyear agreement with Protocol Computers to jointly develop protocol conversion products for use on Net/One. The initial products provide conversion from asynchronous ASCII to 3270 bisync and SNa operation, and 3270 de-conversion to asynchronous ASCII. these products allow the Net/One network user to access different IBM host computers from personal computers and other ASCII terminals, and afford IBM 3270 terminal the ability to access non-IBM host computers and networks.

Corvus Systems of San Jose, California has also joined with The Systems Center of Irving, Texas to provide an SNA gateway so that micro users on its Omninet local-area network can connect to remote mainframe computers. The Systems Center developed the software for the gateway, which provides communications between applications programs running in a host mainframe computer and on local PCs. It also enables PCs to emulate IBM 3270 terminals for direct communications with IBM mainframe computers. In one of the first applications of the product, the Omninet-SNA gateway will link microcomputers installed in 1600 Holiday Inns worldwide with the corporate mainframe computer in Memphis.

Server Extend PC's Reach

An extra dimension to micro-to-mainframe communications was introduced last September when Banyan Systems of Westboro, Massachusetts unveiled its virtual networking system, Vines, and a 32-bit supermicro optimized to function as a network server. The companion softare facilities to location, movement and use of information in both PC networks and micro-to-mainframe environments. It includes a sophisticated naming and addressing data base, called StreetTalk, which permits network users to locate information, other users and shared resources anywhere in a network without knowing their exact location.

There are three major functional elements to the Banyan virtual networking system: front end, back end and services. The front end connects the server to multiple local-area networks, while the back end connects the server to various host processors and wide-area networks. Between the front and back ends reside specific, proprietary service applications. A portable, flexible communications protocol connects disimilar computer interfaces and data representations in a user-transparent fashion. StreetTalk lets users locate and access services and devices independently of their locations on the network.

Multiple LANs are supported via the front end so users can mix network types, switch from one to another or migrate to a network without obsoleting prior network investments. Also, because the server supports a variety of PCs and different operating systems, users can choose PCs based on performance and application needs, and can migrate to new designs for future applications. Once a PC is connected to the server's front end, it gains access to any service available on that server, to any connected host computers, or to other connected Banyan servers.

In the back end, full protocol support is provided for communicating with host minis and mainframes, with public data networks and with larger networks that include additional Banyan servers. The back end supports two levels of host access: the first, file transfer and terminal emulation, allows hosts to transfer files to PCs that emulate remote terminals; the second level involves complete, transparent access to host-provided services such as files or mail. Also, large distributed networks with many Banyan servers can be configured via the back end. As a result, a PC attached to one server can access services on any other server, with the operation transparent to the PC user because it appears as a single service environment.

IBM Blesses Concept

IBM blessed the micro-to-mainframe concept in the fall of 1983 by introducing a version of its personal computer, the o270 PC, giving users the ability to access multiple host computer applications while retaining the unit's personal computing capabilities. Information can be displayed simultaneously in seven windows defined by the user. Each window can be made larger or smaller by the user, who can work with the data in any of them and move easily from one to another. Four can be from interactive programs in host computers such as IBM 43XX or 308X processors. Two are for local notead sessions, through which users can write messages or personal memos, maintain a calendar and transfer data between screen sessions. The seventh window is intended for personal computing sessions.

The 3270 PC Communicates with any IBM System/370, 308X or 43XX processor via an IBM 3274 control unit. Users can communicate via electronic mail, create and send data files through networks, obtain data from corporate data bases for local use by personal computing functions, or access data from public information networks.

Even more capabilities are possible with the IBM PC XT/370, which is actually three workstations in one. It can be used in a standard IBM PC XT (computer) IBM PC XT - An IBM PC with a (slow) hard disk. The XT was released in March 1983. It had an Intel 8088 CPU. The XT/370, released in October 1983, added IBM 370 mainframe emulation, and the XT 286 followed in September 1986 with an Intel 80286 CPU  mode. In addition, it can be used as a System/370 VM/CMS VM/CMS - Virtual Machine/Conversational Monitor System  workstation or as an IBM 3277 display terminal connected to a host computer. With usually no more than two keystrokes, users can switch between two pre-selected modes of operation. Users can transfer programs and information from a host processor to their IBM PC XT/370 workstations, where they can create and edit files, compile and execute programs and generate reports, subsequently sending information back to the host computer.

IBM has also announced its intention to link the IBM PC network to its future token-ring local-area network, giving the networked PCs the ability to communicate with IBM host computers and applications. The IBM PC Network is a low-cost, broadbankd peer-to-peer local-area network that enables IBM PCs to share data and peripheral equipment. IBM says the token-ring network will be built on the IBM Cabling System and will be compatible with SNA.

Last November, Sperry joined the fray with a micro-to-mainframe product line supporting the Unix operating system Noun 1. UNIX operating system - trademark for a powerful operating system
UNIX, UNIX system

operating system, OS - (computer science) software that controls the execution of computer programs and may provide various services
. The product line links the Sperry personal computer and the 1100 Series mainframe computers, as well as two new machines: the Sperry 5000 Series of multi-user micros and the Sperry 7000/40 super minicomputer.

Based on Motorola's 32-bit MC68000 microprocessor, the Sperry 5000 Series includes four models that support Unix System V Unix System V - System V  and accommodate from one to 64 users. The Sperry 7000/40 system, a supermini A large-scale minicomputer. Note: Supermini is not the same as mini-supercomputer.  supporting up to 128 users, is designed to optimally run the Unix operating system and the C programming language.

Digital Equipment computers are also the target for a number of micro-to-mainframe products. The Mobius software system from FEL FEL - Function Equation Language. Programs are sets of definitions. Sequences are lists stored in consecutive memory. "FEL Programmer's Guide", R. M. Keller, AMPS TR 7, U Utah, March 1982.  Computing of East Dover, VT fully integrates Digital's VAX (Virtual Address eXtension) A venerable family of 32-bit computers from HP (via Digital and Compaq) introduced in 1977 with the VAX-11/780. VAX models ranged from desktop units to mainframes all running the same VMS operating system, and VAXes could emulate PDP models  and DECsystem-10 and 20 host machines with CP/M (Control Program for Microprocessors) A single user operating system for the 8080 and Z80 microprocessors from Caldera, known since 2002 as The SCO Group. Created by Gary Kildall of Digital Research, CP/M had its heyday in the early 1980s.  and MS-DOS micros, including the IBM PC. Mobius allows the microcomputer program, without modification, to access host data and peripheral devices as if they were physically resident on the micro. For example, Mobius allows any microcomputer spreadsheet program to use host files in the same way that it uses files on the micro's own disk drive.

Similarly, Mobius users can acces host devices and run host programs as if they were the micro's own devices and programs. Direct access to host resources usually eliminates the need to transfer files. However, when file transfer is desired, it is accomplished with the MS-DOS "Copy" or the CP/M "Pip" command.

Linkware Corporation offers a file server called VAX:Information Server, which facilitates the transfer of information between popular personal computers and Digital VAX minicomputers running the VMS (1) (Virtual Memory System) A multiuser, multitasking, virtual memory operating system for the VAX series from Digital. VMS applications run on any VAX from the MicroVAX to the largest unit. See OpenVMS.  operating system. The Waltham, Massachusetts firm also provides a similar file server for operation in an IBM VM/SP See VM.

VM/SP - Virtual Machine
 environment. Since the PC interface is identical in both products, a user can access both IBM mainframes and VAX minis from the same PC. Effectively, the PC can act as a front-end processor, shifting files from the VAX to and IBM host and vice versa VICE VERSA. On the contrary; on opposite sides. .

According to the firm's president, Larry DeBoever, the VAX-Information Server is designed for companies that have an IBM mainframed running VM/CMS, surrounded by minicomputers and other processors. "These companies may have more than one VAX, but they have no way of distributing information among their IBM, VAX and PC equipment," he states.

The VAX:Information Server can be used to communicate with IBM PCs or compatibles running PC-DOS, as well as Digital Rainbows running MS-DOS or CP/M-86 or Lee Data personal computers running MS-DOS.

Intelligent Technologies International of Palo Alto, California also provides access to IBM and Digital host computers with its PC Express, which emulates 327X terminals for SNA network applications, as well as Digital's VT52 and VT100 terminals. Persoft of Madison, Wisconsin offers a software package called Smar-Term, which provides VT52 and 100 emulation, and also turns on IBM PC into a Data General D100, 200 or 400 terminal. Similarly, Insurance Technology Consultants of Orange, California supplies an emulator that allows an IBM PC or compatible to replace a Honeywell VIP 7200, 7301, or 7303 terminal.

Software Suppliers Join Fray

Major software suppliers, such as Cullinet, McCormack and Dodge, and Informatics General have also developed micro-to-mainframe links to supplement their host-based software offerings, and to facilitate access from popular micros. Interactive PC Link from McCormack and Dodge, for example, is capable of directly accessing any IBM mainframe data in VSAM (Virtual Storage Access Method) An IBM access method for storing data, widely used in IBM mainframes. It uses the B+tree method for organizing data.

VSAM - Virtual Storage Access Method
 files. The data may be downloaded into Lotus 1-2-3 or almost any spreadsheet and interfaced with Millennium, a financial-application software package. The PC user can then employ the spreadsheet data to update mainframe files that are running under Millennium.

Similarly, Software International Corp of Andover, Massachusetts offers IMS/DC and CICS versions of its Smart Link micro-to-mainframe package, allowing users of IBM PC and compatible computers to download selected data from their IBM host-based General Ledger General Ledger

A company's accounting records. This formal ledger contains all the financial accounts and statements of a business.

The ledger uses two columns: one records debits, the other has offsetting credits.
 and Financial Reporting System, manipulate that data using popular spreadsheet products, and load the results onto their mainframe.

On-line Software International takes a different approach. Its Omnilink is "generic" micro-to-mainframe software link so users are not locked into a vendor's mainframe or PC software. With Omnilink, executives using IBM PCs or compatibles can access files from IBM mainframes without knowing computer languages or complication procedures.

Running as an application under IBM's CICS teleprocessing monitor, Omnilink provides multi-directional file transfer, allowing users to download data from mainframe to PC, upload from PC to mainframe or route data from one PC to another. Omnilink also permits selective extraction of data from mainframe files so you download only what's needed.

Electronic Technology of Duluth, Georgia combines a micro-to-mainframe link with an integrated information management system in its Baseline product, which works with IBM mainframes and PCs. President Ronald Pittman says that Baseline's menu-driven commands require no programming or data processing expertise. The optional Host Processor Extension allows easy extraction of data.

Informatics has joined with VisiCorp, Lotus and Ashton-Tate to develop a series of software products that link PC packages with IBM mainframe data. Known as VisiAnswer, Lotus/Answer and dBase/Answer, the packages permit IBM PC users to access virtually any IBM mainframe file or data-base management system, and allow them to manipulate the data on their PCs. To maintain data integrity, the DP manager can specify which portions of the data base individual microcomputer users can down or upload and manipulate.
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Author:Edwards, M.
Publication:Communications News
Article Type:evaluation
Date:Mar 1, 1985
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