The X/Open Group Ltd non-profit company for setting and promoting standards for Unix applications, outlined a series of technical directions at the Uniforum conference, emphasising that it is at last showing signs of progress on the key area of networking. The first fruits of the work in this area, the X/Open Transport Interface, is derived from AT&T’s Transport Level Interface, which was announced with System V.3, but with several modifications. X/Open technical committee chairman Mike Lambert said the modifications included work on event handling to support multiple transports and enable the implementation of servers, and removal of the dependencies on AT&T hardware. Since X/Open is concerned only about providing portability for applications, the group restricts itself to specifying interfaces rather than full communications protocols, and the Transport Interface is intended to be independent of underlying networking regimes. We know it can run on an ISO stack and on an Internet stack, and because of the origins [of the interface] we’re pretty sure it will run on StarLAN, Lambert said. The next round of interface definition work will address higher level services, and a particularly important area is the production of a transaction processing interface for distributed applications. Based in part on the original study commissioned by the group and presented last year, the interface is in concept at the level of IBM’s APPC interface, but Lambert noted that the need to provide data integrity will also have ramifications at the operating system level. With Unix in its current form, You can’t predict if something has been written to disk – which makes it hard to implement reliable transaction processing. The first phase of the Group’s graphical interface definition, meanwhile, comprises standardisation on the X.11 release of the X Window System from Massachusetts Institute of Technology, and Lambert said that in the controversial area of the look and feel of Unix systems, the Group is evaluating which of the contenders it would be possible to use; it is looking at several of the toolkits produced by members of the X consortium of vendors. Microsoft has proposed to X/Open that it adopt Presentation Manager – the forthcoming screen interface for the OS/2 operating system – as a standard interface and Lambert confirmed that the offer was of the nature of putting aspects of Presentation Manager into the public domain – a move that could defuse problems associated with the proprietary nature of the product. But he said that reports that X/Open was already actively considering adopting Presentation Manager were wide of the mark.
