Although DEC’s main purpose the other day was to announce the new DECnet/SNA Data Transfer Facility (CI No 671) it took the opportunity to add some statements of intent for the next 12 months regarding the addition of access to DisOSS Distribution Services – it currently offers only access to Library Services; enhanced connectivity, that […]
Although DEC’s main purpose the other day was to announce the new DECnet/SNA Data Transfer Facility (CI No 671) it took the opportunity to add some statements of intent for the next 12 months regarding the addition of access to DisOSS Distribution Services – it currently offers only access to Library Services; enhanced connectivity, that is to say faster gateways with higher throughput; support for the VM/370 environment; the directing of DECnet, Open Systems and SNA traffic over private X25 networks so reducing the need for dedicated SNA networks; and connectability and strategic networking for for IBM terminals and desktop computers. DEC’s stated aim is to provide simplicity of use for the end user in mail and document exchange. Currently DEC’s interface to the mail system is its office automation product All-In-1, and the company already has an MRX Gateway allowing All-In-1 users access to X400 message handling systems.
However, it intends to link to proprietary systems too. It promises to extend its DisOSS access to include Distribution Services as well as Library Facilities so users can mail documents without having to convert between different document formats. DEC also intends to reinforce the concept of integrating network to network by providing an interface into IBM’s SNADS SNA Distribution Services – the DEC system will play the part of an office systems node within SNADS. It will also be offering an interface into the Profs Professional Office System. The physical communcations link underpinning the announcement was the DECnet/SNA Gateway of which DEC’s interconnect product manager Andy Bray said gnomically ‘this concept will continue although the physical implementation is free to change’ and DEC would be ‘keeping up with the new technology without changing its architectural approach’. DEC wll be increasing the overall throughput and the number of sessions that can be supported by a gateway without changing the user investment in VAX-based access software. DEC is not, however, looking for other implementations of IBM interconnect. In fact, it intends to extend support for a direct SNA connect facility – VMS/SNA – from the MicroVAX alone to the entire VAX 8000 series. DEC will also be offering ‘significantly’ faster interconnect paths between DEC and IBM environments, possibly through direct channel connection and it will be offering the current IBM interconnect capabilites to users outside the MVS environment. The first priority is IBM’s VM/370 users. For customers implementing X25 networks, DEC will be offering current SNA interconnect over X25 networks, cutting down on the requirement for SNA leased lines. Bray said these would be available within 12 months and addressed the concept of the universal workstation where the user would access a number of multi-vendor applications from a singel terminal or Personal. DEC’s objective in IBM’s case is to offer connection for IBM terminals and Personals into DEC networks which would then use DEC’s SNA interconnect to complete the link to the mainframe. So far DEC has provided an implementation of DECnet for MS-DOS effectively turning the Personal into a DECnet node on Ethernet and last month it announced VAXmate ‘network integration kits’ for Personals. Taking this a stage further, DEC is going to offer some of its existing VAX-based access routines to run under MS-DOS so Personals can communicate directly across Ethernet via the DECnet/SNA gateway. An MS-DOS version of Data Transfer Facility, DTF, for example, would enable the full range of file transfer facilities between micro and mainframe via the DEC network. DEC already offers 3270 connection on its DHCF product and VIX, a viewdata product, which provides access to videotex databases for DEC and IBM terminal users. However its ultimate goal is complete DEC terminal transparency for IBM terminal users so that they can run any VAX-based application, so opening up DEC’s environment to users while preserving their investment in Personals and terminals. Data Transfer Facility, which was announced l
ast month, is a mechanism for giving users bi-directional file transfer between DEC and IBM networks. Although it is a VAX-based software product, it also consists of a component that runs on the IBM mainframe – both available and supported by DEC. File transfer can be from DEC to IBM and vice versa, either interactively or in batch mode. The DTF can be used to copy files betweeen two IBM host systems using the DEC network as a connection path, and the end user gets a familiar VAX user interface.
Complex IBM records
The the DEC user will invoke the normal file management utilities, for example, the COPY command, or existing applications, designed to access DEC files, to reach information on the IBM mainframe. DEC believes this makes it as easy, if not easier, for a DEC application to access IBM files than it would be for a comparable IBM application. Interconnect product manager Andy Bray highlighted the biggest drawback of file transfer as the loss of data due to network or system problems which require a complete restart of the transfer. DTF has a checkpoint/restart capability to counter this. This means a partially complete file transfer can be continued from where it left off. This recovery facility can be used for transfer between two IBM systems, using the DEC network as the ‘backbone’. DTF converts file types between those on the IBM host and on the VAX and converts data types automatically. DEC uses its Common Data Dictionary to let the content of ‘complex IBM records’ be predefined and then converted automatically during the file transfer to a format familiar to the DEC user. Security is taken care of by the IBM host-based component linking into standard IBM security facilities to prevent unauthorised access to files. At the VAX end, security is provided using VMS file protection methods. DEC also upgraded its existing products for document interchange: Version 1.3 of the DisOSS Document exchange facility now allows mail to travel from an IBM to a DEC system without the laborious need to register each DEC user as a known DisOSS account. DEC also enhanced its DECnet/SNA VMS Advanced Program-to-Program Communications/LU6.2 product to give improved capabilities to the programmer wanting to use LU 6.2 to link IBM and DEC applications.