3174 controllers are enhanced to add oomph to 3270 devices
The new Configuration Support-B Release 4 Licensed Internal Code works in conjunction with the 3270 Port Expansion Feature to increase the 3270 Category-A device capacity from 32 to 64 terminals (CI No 1,596). It also provides enhancements to ASCII session security, X25 data transmission, on-line tests, and Data General Dasher 210 emulation. Other announcements include a 4Mb Storage Expansion Feature for 3174 Models 21H, 21L, 21R, 22L, 23R, 61R, 62R, and 63R, which expands the maximum control storage for these models from 4Mb to 6Mb. The 3174 Model 23R is a new rack-mountable model that provides Token-Ring support, and the 3270 Port Expansion Feature will be available March 29, brought forward from June 28.
Reduces floor space
The Configuration Support-B Release 4, working in conjunction with the 3270 Port Expansion Feature, enables a single 3174 Controller – Model 11L, 11R, 12L, 12R, 13R, 21H, 21L, 21R, 22L, or 23R – to attach up to 88 devices of 64 3270 Category-A devices plus 24 ASCII devices. This doubles the previous maximum of 32 3270 devices. The 3174 Model 23R provides a rack-mountable 3174 with capabilities similar to the floor-standing Model 13R. The rack-mounted design reduces floor space and power requirements while providing Token-Ring attachment for up to 64 3270 Category-A devices and 24 ASCII emulation devices. The Model 23R includes an integrated communication adaptor that can be used for alternate initial microcode load access to a host via a communication link such as the EIA RS-232D/CCITT V.24/V.28 or CCITT V.35. Configuration Support-B Release 4 also provides additional security measures for ASCII devices in SNA host applications, and when an ASCII device powers off from SNA host applications, the session cannot be accessed by another user. IBM says that a more efficient algorithm is used for assembling information into X25 packets, reducing traffic through the X25 network and reducing connection time. Current versions of IBM access methods, operating systems, application subsystems, and 3270 applications that support and conform to the appropriate attachment and data stream architectures – SNA, BSC, 3270DS, SDLC, and X25 – support Configuration Support-B Release 4. Existing functions for control unit terminal, distributed function terminal, Token-Ring device attachment, and system processor attachments for the 3174 models remain unchanged. The 3174 Model 23R contains both a Type 3A Dual Speed Communication Adaptor and a Type 1 Teleprocessing Communication Adaptor. It can be customised as a Token-Ring attached controller or as a communications controller, with or without a gateway. The limitations associated with Configuration Support-B Release 4 are the limitations with the 3270 Port Expansion Feature. 3174 Models 21H, 21L, 21R, 22L, and 23R require two 3299 Model 032 Terminal Multiplexers to access 64 3270 ports. Up to 56 3270 ports can be accessed with one 3299 Model 032 and any combination, up to three, of Terminal Multiplexer Adaptors and or 3299-001, 002, or 003 multiplexers. Non-SNA host support only has 32 host addresses, and a non-SNA controller can access more than 32 sessions by defining additional sessions to use other host connections via the Asynchronous Emulation Adaptor or Concurrent Communication Adaptor.
The 3174 ISDN Rate Interface Adaptor brings ISDN to remote PS/2s
The 3174 Integrated Services Digital Network Basic Rate Interface Adaptor provides downstream communication to PS/2 devices with the ISDN Interface Co-Processor/2 Model 2 and ISDN Co-Processor Support Program Version 1.1 installed at speeds up to 64Kbps. It has four ports, each providing two 64Kbps data channels, as well as a 16Kbps signalling channel, enabling support for up to eight remote PS/2 ISDN workstations with no contention. IBM says it is its first controller that supports Integrated Services Digital Network as well as providing support for remote workstations over end-to-end digital communication lines. The 3174 ISDN BRI Adaptor and Configurat
ion Support-C may be installed in a number of 3174 Establishment Controllers. Furthermore, communication through the 3174 ISDN BRI Adaptor to the remote PS/2 with the ISDN Interface Co-Processor/2 Model 2 and Co-Processor Support Program Version 1.1 installed is supported via ISDN Data Link Control protocol. From the perspective of VTAM, remote ISDN workstations appear as multidropped downstream physical units Type 2.0, and group poll support is consistent with the 3174 Token Ring Gateway implementation. Both the 3174 ISDN BRI Adaptor and Configuration Support-C will be supported by the current version and release of NetView. The ISDN feature supports attachment to AT&T 5ESS, Northern Telecom DMS-100 and announcement of capability for other ISDN switches, or given release levels of these switches, will depend on network availability and IBM’s characterisation of the network interface. Selection of ISDN networks for attachment will be based upon IBM’s technical and business judgement in addressing the requirements of its customers. The Cabling System Type 2 Voice Grade Media has been designed for analogue and digital telephone applications and is generally suitable for ISDN transmission. Although the BRI Adaptor may co-reside in a 3174 with the Concurrent Communication Adaptor, remote ISDN workstations supported by the 3174 ISDN BRI Adaptor may communicate only with the primary host, and communication is not supported to secondary hosts. A Token Ring Gateway feature and an ISDN BRI adaptor may co-exist in a 3174 Controller, but communication from a Token Ring workstation to a remote ISDN workstation is not supported. The ISDN BRI Adaptor will be available September 27. The ISDN BRI Adaptor costs $4,800 to which must be added a minimum maintenance cost of $360 per annum.
The Integrated Services Digital Network Interface Co-Processor/2 Model 2
The ISDN Interface Co-Processor/2 Model 2 provides attachment to the Integrated Services Digital Network Basic Rate Interface. When operating with supporting software, Interface Co-Processor/2 enables full duplex data transmission at 64Kbps concurrently over each of the two information channels, under the control of a 16Kbps control channel. When installed in a PS/2 Model 50 and higher range models, IBM claims that the ISDN Interface Co-Processor/2 Model 2 enables ISDN connectivity not only to other similarly equipped PS/2s, but also to a range of systems using either the 7820 ISDN Terminal Adaptor or the 3174 ISDN Basic Rate Interface Adaptor. Available from June 28, the ISDN Co-Processor/2 Model 2 carries a $1,200 price tag.
