Pa 70 PO WEEKNAPPLIGATION DEVELOPMENT. JU.yY 10, 1989 "SAMA: Fulfilling the Need for an Integrated Environment and programmable workstations. The Systems Appli- cation Architecture, according to IBM Chairman John Akers, is the technology that will have the largest effect on IBM customers over the next five to 10 years. In many ways, the transition to SAA represents the most, significant: change in IBM software environments since the introduction of the System/360 in 1964. As the name implies, SAA is an archi- tecture for building enterprisewide sys- tems of applications. But what exactly isa software architecture? According to the dictionary, an archi- tecture is "a style and method of design and construction." As it applies to soft- ware, the word has also come to mean a specification of the fundamental ele- ments of structure. Thus, we can view SAA as the specification of both the fundamental elements of the enterprise- wide application structure and the style and method by which those elements are combined to build applications. SAA isn'tva product. or family of prod- uets for building enterprisewide applica- tions. Its a consistent, open set of speci- fications for how these applications will be built. Many vendors, including IBM, have recognized the need for integrated com- puting environments. Today, organiza- tions often mix many types of comput- ers. All the machines serve different, but sometimes overlapping, functions. They are programmed differently, have differ- ent user interfaces, and there's little communication between them. It's not. easy to build applications that make the tremi of differing machine capabil- machines are seamlessly connected with applications working cooperatively across machine boundaries. Each of the machines is assigned the functions that it does best. A primary strength of the program- mable workstation is its ability to act as the user's window into the EIS. It pro- vides a consistent and easy-to-use inter- face for all applications. The applica- tions that are accessed might be execut- ing locally on the programmable workstation, remotely on any other ma- chine in the EIS, or cooperatively among multiple machines. 'The corporate and midrange host What SAA Aims to Provide 'A durable architectura : Flexibility for evolutiondty growth Il » Ability to link disparata IBM systems ln a company. | » Ability to hdndla varied workloads | j MA consistent šystem detoss d company Ability to leverade existing Investments feel. While primarily intended for the programmable workstation, CUA con tains a subset that čani be used Tor not: programmable terminals. This allows ap- plications to take full advantage of menu-driven, windowing, graphical, pro- grammable-workstation interface capa", bilities, and still maintain existing appli- ; cations for non-prograrnimable terminals. CCSis the specification for inter- program communication. It is based ; heavily on IBM's System Network Archi- tecture (SNA) but also includes support for X.25 protocols and Open Systems In- terconnect. (OSI) protocols. Most of CCS, such as LAN support, is shielded from the developer and user. Only the top-lev- el program-to-program services are di" rectly accessible. GPI specifies the developer's tools, in- cluding programming languages and ser- vices. The products that implement the CPI will be used for building EIS appli- cations. Different products will exist on different platforms, but to be SAA-com- pliant the programmer's interface to the products must be consistent and must follow the CPI specifications. IBM has specified SAA for four main operating system environments: MVS and VM on the System/370, 05/400 on the AS/400, and OS/2 on the program- mable workstation. The OSI and X.25 communication protocols allow connec- tion to other non-supported envi- ronments. ( J J What: About Unix? While IBM would prefer that everyone use 0S/2 on PS/2s, the company is aware that many users prefer Unix on workstations. For this reason, the devel- opment directions of IBM's version of Unix, AIX, parallel those of SAA. The programming and communication interfaces will gradually become the same between SAA and AIX. This will allow Unix systems to be seamlessly in- corporated as part of the enterprise in- formation system. Organizations that prefer Unix will be able to make Unix, ie than OS/2, the window on the support the user interface, database and program-to-program communication functions. Furthermore, the functional components of the application that are best suited for different machines must be isolated. For example, an application that gath- ers data and updates a corporate data- base would divide its functions between the host and the programmable work- station. Support for the user interface, as well as the editing and validating of user input, would be performed on the programmable workstation in a highly interactive input session, Once the data is gathered and edited, the data would be sent transparently to the host for ad- 1 1 ( John Avakian The tools are not all in place yet for building EIS applications, but the archi- S č tecture is wellunderstood. Organizations o a SAA isn't a product for building enterprisewide that wish to use SAA as early as possi- environments is to provide seamless applications. It's a consistent, ke should start designing and bullding Connections between all'the machin Jor how open set of specs new applications with the clear: separa- stni baba: k Ra or these applications will be built tion of functions reguired for SAA. As tributed freely rabe them. Additional tools that implement SAA become avail- onem include the h SE EN a en a affected modules can be con- Such ver ; tčee. ela or all applica. Computers are best at eoordinating mul: ditional technol dia ene pe ska programmers with a consistent tiuser access to databases and transac porti N sa "IN deseril ment environment that makes Mon: processing applications. 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(Reed, is to specihy tko (lune "7 'S available through High Pro- olbM cal the computing system of the written nono be desni ani ai taceh toe computer These kev Mo pola ine, 9 Marble an "enterprise inf sys- Work cooperatively. The criti- Access (CUA), the ass. (800) 242-1240. For infor- tem," or EJS. As sk cal funetio Či user SI;o Common ' mation on please contact (in Ks jo typlcaliy mani pr many dir. ana ga to divide aa soda (CC9), tre machine-machine: in Sea Sile led Šttes and Canada) Tel lerent types of machines, along boundaries Common 1 porate malnframes, midrange machinas »Pe4018 to be distribu that alow the tertace (CPI Prograrming Santa Mona, Caik u Z4I 100 SL, o this invol ted. For SAA, programmer interface, Calif. 90402 (213) 394. Ves solating functions that SAA-compliant user interfaces will Kai In Europe, contact Savant, 2 Carnforth, La: LA United Kingdom. ( 0524) 734 kli