Revolutionary plans for the next generation of IBM Corp’s strongest computer family, the AS/400, are starting to crystallise, insiders who have been watching a power struggle at IBM’s Application Business Systems Rochester Laboratories. According to the July issue of our sister magazine IBM System User, the AS/400 will go through several unexpected twists and turns as it becomes substantially more powerful, more distributed and more flexible than today’s models. There are several surprise elements to IBM’s plan. These include the incorporation of input-output processors – 80486s presumably running the OS/2 operating system, and the use of 65-bit address central processors. These changes are in addition to the adoption of Power architecture RISC processors and some parts of the Taligent operating system being developed with Apple Computer Inc. Surprisingly, say the sources, IBM is considering a plan to go through not one but two central processor changes over the next two or three years. This will involve a change from today’s 49-bit address processors to 65-bit processors in the AS/400 H models. After this, it will switch to 65-bit Power Architecture based systems. The 65-bit processors will consist of the 64-bit ‘RIOS-2’ Power Architecture RS/6000 processor with an extra bit to be used for a security tag. According to IBM, compatibility of existing programs will be guaranteed ‘whatever happens’. The latest plan for the AS/400 was developed by a task force set up by John Thompson, general manager of the AS/400 business unit,Application Business Systems. The Task Force was given a wide-ranging brief to design an upgrade path based on the best and most effective technology it could find. Its plans killed off a rival upgrade path being developed under the codename ‘Superior’, say insiders. The main surprise in the new development plan is the use of input-output processors based on OS/2, or a variant or successor of OS/2. This would improve the client-server capabilities of the machine, give a graphical user interface, and access to the vast array of Windows and OS/2 applications. The processors would almost certainly be the PowerPC chips under development by IBM, Apple and Motorola Inc. These will also be able to run AIX, IBM’s version of Unix; Taligent, its object-oriented operating system which will at first complement, and ultimately replace OS/2; and Microsoft Windows NT. Parts of the Taligent object-oriented technology will also be used in the main operating system, OS/400. However, it is not clear if the plans include the possibility of running OS/400 as a personality on top of the Taligent kernel. Under the new design, OS/400 will get simpler, and become more open, in the releases scheduled at the end of this year. Bigger changes will be made in 1995 with OS/400 4.1. The new more open AS/400 in 1995 (the AS/500?) will include close software integration between OS/400, OS/2 and other versions. The under lying hardware changes are likely to boost price-performance at a higher average rate than the 30% a year being achieved at present.
