; i s a NM MM u me di Ĺ A Ĺ˝ z si z 2 ri baleji Sue NM TRE PRIM ; za O ske di iN Na Me PâO MA eoâââ ; a A ra Me arki Ja ; Vetrne i i Mi tal] kadim ; sa de ] 1 a a ] daj: p m; a . Tai PAGE O2 puter hardware, software, data- ments and, com: municattons eh- Corporations < are moving rap- idly toward im- UAMES MARTIN | plementing large- scale strategic systems that integrate all components of an enterprise. These complex systems will be based on the installation of net- works capable of supporting large num- bers of PCs, file servers and links to mainframe systems. Both data and pro- cessing modules will be distributed | throughout the network in cooperative- processing and client/server appli- cations. | Large corporate networks of comput: ers are being implemented both to com- puterize entire organizations and to es- tablish intercorporate links with suppli- ers, retailers, customers, dealers, distributors and financial organizations. Among the communications mecha- nisms used are E-mail for person-to-per- son interfaces; electronic data access for person-to-application interfaces; and electronic data interchange for applica- tion-to-application interfaces. Many corporations have greatly in- creased the strategic value of their com- puter systems through intercorporate networks used for electronic data inter- change. These networks have enabled them to reduce trading delays, provide better customer service, increase their competitiveness in the market; and re- duce costs. In addition, these networks can reduce transportation expenses, im- prove production scheduling and de- crease waste. In addition to building networks of PCs and mainframes, organizations will link other communications functions and make them accessible through the PC. Voice mail, E-mail and fax will all be access] ble through the individual's PC. Gateways to outside networks will be used to tie into real-time news wires, To build these complex networks, zapove te OE lene to , processing power of local PCs must â2. the process' technigue to imple- orks. LANs will utilize PCOs at the rate of 100M bps. Âťgrated bervices Digital spread use of ISDN will facilitate vide simpler access to highspeed. switched digital circuitg. To implement corporatewide commu- nications networks, the current incom- patibilities between hardware and soft. ware systems must be resolved. Despite major commitments to international communications protocols, problems still exist in linking hardware ie software systems f different: vendors. k obesim ustrates the type of inter" connections that are available to link both IBM and non-IBM systems. The ex: araple shows communications interfaces between SAA applications, applications running under AIX (IBMs version of Unix) and other systems (such as Sun workstations under Sun OS, Unix workstations under Unix System V or DEC VAX computers under VMS). To communicate effectively among these diverse systems, it's necessary to specify multivendor architectures that define a standard set, of networking ser- NPPLJED INTELLIGENCE [Integrated Multivendor Solutions Are Crucial to Networking Standard Networking Services Reguired CPE IEEKNAPPLIGATION DEVELOPMENT H ments, together with OSI international protocols, implement the SAA cormmuni- As discussed in a previous article, SAA provides a comprehensive set of facilities to distribute both process and data across IBM PS/2, AS/400 and Sys- tem/370 computers. Interprocess com: munications between IBM machines 15 supported by SNA conventions, includ- ing Synchronous Data Link Control | (SDLC), LU 6.2 peer-to-peer communica: tions protocols and Token-Ring LAN protocols. Access of data located on re- mote, non-IBM computers is supported within SAA through the use of standard OSI protocols including X.25 packet For Enterprisewide Interconnectiohs The Standard Data-Tranisfei' Protocol Is Based oi SGL; Standard Communications Protocols dl pa a a a Sao SAA NU application H j ZNE NA Ek 7 A Ĺ˝A, repiip, osi V. Itielude SNA, TCP/IP atid OSI | SNA, TCP/IP, OSI > o Othet applications John Avakian Many corporations have greatly increased the strategic value of their computer systems through intercorporate â Vices, data-transfer protocols an a- transfer media. The figure selena representative multivendor architecture based on SOL-compatible data-access - standards and communications proto- poki supported by IBM's SNA, TGP/IP po Open Syplema juter Interconnect (OSI) in. nm tions protocols. se Systems Network Arohitecture Systema Application Architecture (SAA) and is used to support, communications: JC m a distributed | | OTV The SNA not rorking area done pgen used by IBM for years to intercon. dissimilar systems. These SNA ele- networks used for electronic data interchange. switching, X.400 electronic mail and TEEE 802 Token-Ring. TCP/IP is widely used to support, net:- works for military applications, univer- sities, research laboratories and manu- facturing applications. Implementations of TCP/IP include the Ethernet LAN based on the Berkeley variant, of Unix, as well as wide area networks using X.25 packet-switched networks for a wide variety of popular computers. The OSI communications model is based on standards defined by the Inter- national Standards Organization. The or- ganization has defined a seven-layer OSI model that forms the basis for a net: Standard protocols defined using the JUHE 11, 1990 working architecture. Fach layer has a OSI model include X.25 packet switch- ing, X.400 E-mail, IEEE 802 Token-Ring and Connectionless Network Protocol used in factory-floor manufacturing op- erationS. TCP/IP is widely used to support Ethernet, LANSs; the OSI model is fre- guently used for X.29 packet-switched networks. It's likely that the OSI model will grow in importance relative to TCP/IP. Supporting Communications The three applications environments shown in the figureâSAA, AIX and non: IBM applicationsâgenerally support one or more of the communications environ- ments shown in the figureâSNA, TCP/IP and OSI The communications-support ca- pabilities of the three applications envi- ronments are summarized below. SAA applications utilize the SNA net: working architecture to provide connec- tivity between PS/2, AS/400 and Sys- tem/370 computers. TCP/IP and OSI protocols are used to support communi- cations with non-IBM machines. IBM's ALX is a variant of Unix that < supports a basic multiuser, multitasking environment. In addition, it provides support for virtual memory, enhanced file management, dynamic configuration, support in the DOS environment for multiple users, multiple interactive ses- sion management and National Lan- guage Support. Communications support for AIX in- cludes TCP/IP, X.25 packet, switching, Sun Network File System (NFS), Ethernet, and Token-Ring LANS, and electronic-mail protocols. These commu- nications facilities enable AIX applica- tions under Unix to integrate well with SAA applications under OS/2. Broader integration between IBM and non-IBM machines may be obtained through support of TCP/IP and OSI net- work architectures. Many computers, such as engineering workstations and Digital VAX systems, provide support for TCP/IP and OSI protocols. The use of . standard communications protocols and standard data-access conventions should be strongly encouraged to provide interoperability between widely diverse computer environments. Next, week, Ill discuss how these ma- jor trends in computer hardware, soft- ware, database and communications en- vironments are affecting the evolution of computer drchitectures. H The concepts embodied in this article are described in the High-Productivity Technology volume in The James Mar- tin Report Series. For more informa- tion on this volume, call (617) 639- 1958. For information on seminars, contact (in the United. States and Can- ada) Technology Transfer Institute, 741 10th St., Santa Monica, Calif. 90402 (213) 394-8305. In Europe, con- tact Savant, 2 New St., Carnforth, Lancs., LA5 9BX United Kingdom (0524) 734 505. specific set, of respo nsibilities within the Äi,