Programmable Network Access demonstrates why IBM believes in OS/2, Micro Channel
Dropped in with little fanfare, IBM’s new Programmable Network Access program for attaching disparate computer systems to either SNA or X25 networks via a PS/2 under OS/2 (CI No 1,301) looks like a nifty little offering. The intention is to enable users to share information and to access applications across heterogenous networks and to manage them from a central point. The first release provides concentration of data traffic from multiple SNA and non-SNA terminals onto a single Synchronous Data Link Control backbone network – SDLC is the standard protocol within SNA where X25 uses HDLC, High Level Data Link Control. In the second release, the PS/2 with the software and co-processor fitted can serve as an X25 concentrator and packet assembler-disassembler and offers protocol and data stream conversions for ASCII terminals, enabling users of those terminals to access SNA or X25 applications more easily. There is also an open, programmable interface so that the product can be tailored to support other devices and protocols and to write distributed applications – and IBM’s Systems Integration Division plans to work with customers to provide custom solutions for a fee to meet their specific requirements from the program. In future, the product will also offer the interconnection of X25 devices over an SNA network. Note that the program not only runs on a PS/2 under OS/2, but makes use of Micro Channel bus master co-processors.
One line supports several clusters
Going into a little more detail, and making it clear that things aren’t quite as simple as IBM initially made them sound, Programmable Network Access facilitates concentration of traffic of multiple SNA terminals onto a single SDLC or X25 link to the backbone network, giving the appearance of an SNA Cluster Controller. It supports the IBM 3174 cluster controller, the 4680 retail system, the Series/1 mini running RPS or EDX with the Communications Facility and Logical Units types 0, 1, 2, and 3 data streams from the IBM panoply of products. Only one upstream point-to-point line is required to connect several cluster controllers, where several links or a multipoint connection were previously needed. Access to the SNA backbone can also be provided through an X25 Packet Switching Network, using Qualified Logical Link Control – but that is supported only by OS/2 Extended Edition 1.2 in Programmable Network Access Version 1.0, as well as the X25 Co-processor/2, which supports bit rates up to 64Kbps on the upstream link. Programmable Network Access provides access to SNA applications designed to support 3270 terminals, such as CICS and IMS, from ASCII terminals, supported by protocol and data stream conversions between the terminals and the network. Terminal emulation services provide IBM 3278-2 screen appearances and keyboard functions equivalent to ASCII terminals. Terminals supported through leased and dial-in connections include IBM 3101, 3151, 3161, 3162, 3163, 3164, the IBM Personal Computer running the Host File Transfer and Terminal Emulation Program, the DEC VT100 and the French Minitel 1B. Eight-bit ASCII character set support enables the use of these devices with national keyboards. Programmable Network Access Version 1.1 supports the same terminals apart from the Minitel, plus the PS/2 in 3101 emulation mode. The program is an alternative to IBM’s Network Terminal Option. X25 devices supported by version 1.1 include X25 Data Terminal Equipment connected to Programmable Network Access via a line or an X25 PSDN; data transfers between locally attached X25 terminals through Programmable Network Access; concentration of ASCII terminal data streams through a CCITT 3X Packet Assembler-Disassembler built into the program; SNA host links for X25 terminals through XI and NPSI; and concentration of all X25 downstream traffic on a single upstream line. For these connections, OS/2 Standard Edition is needed, with the Multiport/2 and Portmaster Adapter/A co-processors.
Support requirements a
re non-trivial
The Programmable Network Access program handles terminal identification and establishes a user authorisation procedure whenever it is accessed via a dial-in connection. Terminal identification enables the definition of a pool of general purpose dial-in ports available to any type of supported ASCII terminal. A configuration utility is provided for the entry and modification of line, terminal and user profiles at set-up time. The configuration process uses hierarchical screens conforming to IBM’s Common User Access element of Systems Application Architecture. Programmable Network Access is designed for full time unattended operation. Once started and doing routine processing, no vital function of the program should require operator intervention, IBM says. The Programming Interfaces enable end-users to tailor Programmable Network Access to unique customer device, protocol or terminal support applications. The Programmable Network Access Tool Kit, a set of C Language data definitions and object code functions – can be used to construct a custom commmunications concentrator. When Programmable Network Access is installed under OS/2 Extended Edition, Communication Manager functions such as Token-Ring support are available concurrently with Programmable Network Access services. A single line to the SNA backbone network can be shared by the Communication Manager and Programmable Network Access using an IBM 786X Fan-Out modem.Users need a PS/2 Model 55, Model 70 or Model 80, or the 7561, 7562, 7568 hard-hat versions; the Real Time Interface Co-processor Multiport/2 Adaptor with Electrical Interface Boards 6265, 6266 and 6267 in Version 1.0, plus 6326 and 6327 in Version 1.1; plus the Real Time Interface Co-processor Portmaster Adaptor/A with Electrical Interface Boards 6362 and 6363 for Version 1.1; and the X25 Interface Co-processor/2 for X25 Qualified Logical Link Control for version 1.0. Upstream attachment to the SNA transport network has to be via 3720, 3725 or 3745 Communications Controllers, or a 9370 with Integrated Communications Adaptor. On the software front, Real Time Interface Co-processor OS/2 support 1.02 is required for anything below OS/2 Extended Edition 1.2; also needed are Realtime Interface Co-processor Extended Services; VTAM 3.1 up; Network Control Program 4.2 up; NetView 2 or later; NetView/DM 1; HCF: 2.1; NPSI 2.1 with NCP 4.3, or 3.2 with NCP 5.2, 3.3 with NCP 5.3; XI 1 with NCP 4.2 or 4.3; Version 2 with NCP Version 5.2 up. The Tool Kit needs C/2 Compiler 1.1; Realtime Interface Co-processor C Language support; and Realtime Interface Co-processor Developers Kit. Programmable Network Access supports a maximum of 31 downstream lines and one upstream line distributed on four Real Time Interface Co-processor boards. Each version, 1.0 and 1.1, is $2,000; further licences are $1,900, and the Tool Kit is $1,500, but don’t all rush at once 1.0 doesn’t arrive in the US until June 1990, and there won’t even be a date for 1.1 until April.
