The European Telecommunications Standards Institute is finalising the specifications for a low-level Application Programming Interface to connect equipment like personal computers to the ISDN, which will form the basis of a Euro-ISDN standard. Simultaneously, the US National ISDN User Forum is deciding on a comparable standard, but in isolation from the European initiative, so that a damaging split in the market seems a near certainty. The rationale for the separatist approach is that global links should be seen as a second step, after the initial hurdle of European and US integration is overcome. This approach has, however, attracted criticism. Hayes Microcomputer Products Inc feels the policy is shortsighted, having developed its Standard AT Command Set for ISDN, which is among those being considered in the US. While emphasising that there is still time for Europe and the US to develop common specifications (since the installed base of ISDN users is still relatively low), Lisa Volmar, product manager at Hayes in the US, commented that …we were a little dismayed that the US and European groups don’t have any interest in talking. Few details about the proposed European programming interface have been released – the details are due to be published in the next month or so – but according to consultant Mark Bogers, national specifications developed by France Telecom and Germany (in conjunction with Deutsche Bundespost Telekom) are to be used as building blocks for the European standard. If this is the case, it seems likely that Europe will be adopting a completely different standard to the Applications Software Interface in the US. There is, however, still a chance that the US and Europe can come closer together on other specifications. This first European programming interface release, a software implementation around Level 3 of the Open Systems Interconnection seven layer model, is part of a two-sectioned project, with a research committee undertaking a study on what the work programme should be. Whether this will decide that integration with the US should be more of an issue remains to be seen. As if to emphasise that even at a national level there are already a large number of diverse interfaces, AT&T Network Systems says that it has developed an extension to the Hayes set. While the company will make the interface available to other developers, it is not going to try and get it formally adopted by official standards bodies, preferring to try and set a de facto standard. Called the AT&T ISDN 7506 and 7507 Applications Programming Interface for telephone sets, the specifications have been incorporated into its new ISDN Client Profile software designed, as is the European interface, to link personal computers to the ISDN. AT&T seems to have been successful in attracting interest from other companies: a development version of the software was tested earlier in the year by Ameritech Services and AT&T at both companies’ Chicago laboratories, and a test is currently being undertaken by an Ameritech customer. Based on the success of the test, Ameritech is considering making the product generally available by the end of the year. From AT&T, it will be available under controlled introduction in August, and later offered for generally availability, primarily through phone companies. AT&T’s software included some interesting features, and as well as caller identification information, it provides notes from the last conversation as well as client information retrieved either from the personal computer or from a central computer over the ISDN phone line. Call logging covers all calls, whether picked up or not, and the program also gives status information if the call was not answered – for example, whether it was transferred to voice mail, a message desk, or answered by another worker. Users can dial numbers by clicking on the client’s name, while all functions (such as call transfer, call hold, and conference calls) can be accessed from the keyboard.
