@make[report] @device[x2700] @majorheading[Telematics] @section[General] Telematics offer a range of X.25 networking products called the Net 25 Product Family including concentrator switches, primary switches, backbone switches, PADs and supervisory nodes. The equipment is sold in the UK by Telematics and also by ICL and other companies including IAL who sell it under their own label. Telematics is certified for use on most public data networks. @section[Hardware Description] The Net 25 switches are based on a proprietary 32 bit bus that is stated to run at 32 Megabytes/sec. There are three models available, the P500, P1000 and P2000. The main difference being the number of processors used and the number of slots available in the back plane. The particular switch, constructed from a P500, confgurations, described as Net 25/XXX are constructed from the appropriate model. The Net 25/100 switch consists of the bus and a general purpose M68000 processor card, a memory controller and memory, either a floppy or a hard disk, and a Network Communications Processor (NCP). A Net 25/200 is derived from a P1000 and includes a 'communications accelerator' which is a two part cache, one part a cache for the general processor and the other part a cache for the NCP. The Net 25/400 is formed by the further addition of one or two extra general processors. The Net 25/800 uses the P200 with an additional two processors. The series are field upgradable to the P2000. The P500 has 2 Mbytes, the P1000 8 Mbytes and the P2000 16 Mbytes of store. The NCP supports a TDM based bus with a scanner with a maximum capacity of 2 M bits/sec. The scanner can support up to 60 'Line Interface Modules', each supporting up to 8 lines (depending on speed). In addition a new module, called a Line Programmable Module (LPM), has been delivered to some customers, although there is no BT approval as yet, with 120 Kbytes of on board RAM. In addition to the support of 2 V24 or V35 ports, the LMP supports up to two expander cards, Line Programmable Extenders (LPE), to which either 8 V24 or 4 V3 lines can be connected. In all cases the level 2 handling is done in one of the 68000 processors. @section[Software Description] The basic operating system, caled TRAX, is used to support a number of tasks which implement the switch software. In addition it is possible to run differnet complexities of Network Management tasks or 'user' written tasks. (A 'user' task is any not written by Telematics.) TRAX is written in M68000 assembler code. The switch software, consisting of a number of tasks to - handle call set up, handle data transfer and an Interface 6 Network Management (INF). The data transfer task is writtin in assembler and the call set up task is written in C. 'User' tasks can be written in either C, Pascal or assembler. @section[Configuration Options] The limits for the number of line cards processor creates are as follows:- @begin[verbatim] Line Cards V24 Line V35/X.21 Lines ---------- -------- -------------- P500 (Net 25/100) 8 64 32 P1000 (Net 25/200) 60 480 240 (Net 25/400) P2000 (Net 25/800) 60 480 240 @end[verbatim] The figures are for the number of lines assuming all the lines are of that type, a mixture may be created by assuming 2 V24 lines for every V35 ones. These configurations assume the use of Line Interface Modules (LIMs) rather than Line Processor modules (LPMs) and Line Processor Extenders (LPEs). If a configuration uses LPMs and LPEs then a 'Line card' can be either LPM supporting 2 V24 or V35 lines or an LPE supporting 8 V24 or 4 V35 lines, bearing in mind that a single LPM can support either one or two LPEs. Thus the consequences of using each LPM is to reduct the maximum connectivity of the switch by 6 V24 lines or 2 V35 lines. The advantage of configuring a switch with LPMs and LPEs is that the constraint of the TOM nature of the NCP is avoided. @section[Line Speeds/Interface Options] Telematics support 64 kb/s in addition to the line speeds in the specification. V24 is used up to 19.2 kb/s and V35 above that. In addition X.21 (in reality RS449 is supported, Both internal and external clocking can be used at any of these speeds. The USA company is doing a T1 (1.56 Mbt/s) and the UK company have 'requested' that a G703 interface is manufactured but they consider that one of the UK OEMs may do it first. @section[Throughput] The following throughput is claimed for the Telematics range. The figures are for data packets only through the switch. There is no dependance of packet size. @begin[verbatim] Net 25/100 100 dpp/s Net 25/200 200 dpp/s Net 25/400 400 dpp/s Net 25/800 800 dpp/s @end[verbatim] @section[Costs] The following List Prices have been quoted by Telematics for the 4 configurations. @begin[verbatim] 10 line: @T{#}30,000 (actually 14 links) 18 line: @T{#}31,000 (actually 20 links) 48 line: @T{#}86,000 (actually 50 links) 100 line: @T{#}135,000 @end[verbatim] The costs include software with the 'lower' level of network management (single switch only). A single licence for the full network management costs @T{#}23,000. The hardware quoted for the 10 line switch is about to be replaced by a new option and reference should be made to ICL for details of it. In addition to the above, various items can be added to the configuration - @begin[verbatim] Extra processor (all) @T{#}10,500 Additional line cards (all) LMP @T{#}5,500 LPE(V24) @T{#}2,500 (V35) @T{#}3,000 @end[verbatim] Any one of the configurations can be field upgraded to the large configuration. @section[Known Problems] @begin[itemize] Management protocols are not in the Public Domain. Guarantee conformity with CCITT, not PSS. Not possible to list or clear calls to a particular DTE address. No dump procedure. No Full Load Sharing. @end[itemize] @section[X.25 Facilities] Fast Select, PVCs and Reverse Charging are supported. Packet and Window size negotiation is supported with a maximum packet size of 4096. In addition the network will segment or reconstruct packets, using the 'M' bit, to allow, for example, a host with a packet size of 4096 to communicate with a host using a packet size of 128. Call redirection is planned for 1986 as part of the X.25 (1984) enhancements. Call Statistics are not compatible with those on PSS. @section[Multinode Networks] Telematic switches connect together to make up a multinode network using a non X.25 protocol between the nodes. Adaptor routing is supported and if an alternative path exists, existing calls are not lost, or reset, when a 'transit' node, or link, goes down. Any node can control the rest, see the section on Control. @section[Addressing] Telematics allows multiple entries in the address table. The table size is only limited by the overall store size. An individual entry can be either a single address or can be made to match and address, eg. 1234 would match any address from 12340000000 to 12349999999. This is not quite as flexible as a 'range of addresses' but by using multiple entries, the differences are fairly minor. A problem is caused because the addresses 1234 and 000000001234 are different. To overcome this will require double outlines for all routing addresses. Full load sharing is not supported. @section[Network Management] Network Management can be performed on a separate machine or the software can be integrated with the switching software on one of the switches in a network. If it is integrated then there could be a performance cost although it is possible to run the management package either at at a priority level less than that of the switching functionsor run the software on a separate processor within the switch system. No explicit charging is done by the current software though the information is present to do charging for calls, for example, to PSS. The management protocols are @u[not] in the public domain, although Telematics would sell us listings etc., to allow community hosts to perform some of the management. It appears that they would @u[not] allow other switch manufacturers to implement the protocols. @section[Statistics] Telematics meet the JNT spec except that there is no explicit code to calculate the percentage utilisation of the switch as a whole. @section[Status Monitoring] Telematics do not report in real-time the number of active calls on a link or the respective address, otherwise the spec is met. @section[Control] It is @u[not] possible to clear a call to a selected address, the rest of the spec is met with the ability to change network addresses on a line link. It is possible to use any network terminal (password protected) for switch control. There are two levels of Network Management/Control Software - 'A' and 'C'. 'C' is a partial form that only allows the operator of a particular switch to control that switch. 'A' adds the ability to look at and control remote switches. At lease one node in each university with multiple nodes, would require either one copy of the 'A' level software or a support management machine. @section[Date/Time Stamp] Complies. @section[PSS Compatibility] Telematics say that they are currently compatible with PSS. However, if in the future there is a divergance between PSS and CCITT then Telematics will @b{guarantee} compatibility only with CCITT. @section[Performance - Packet Transmission] @begin[verbatim] Call Request 30ms Data Packate 4-6ms Clear <30ms @end[verbatim] @section[Availability and Reliability] It was claimed that the Net 25 series would meet the reliability section of the specification. It was noted that line cards could be replaced on live systems, so that only a failure in a central module would force an entire node to go down. Redundant systems, ie line cards shared between two nodes could be constructed if necessary. Only figures for hardware reliability are stated - in terms of 7000 hours MTBF for the kernel system. It is claimed that field information to date backs up that figure. An availability for an entire node is quoted at 99.9%. @section[Operations] It is not possible with the current software to automatically dump the store to backing disk in the case of a complete failure. If failures of individual tests occur details of the failure are printed out on the system console. There is not a separate handler for each link in a system and consequently it is not possible for an individual link to fail, and require a reload, that occurs on the GEC switches. @section[Configuration] All configurations, including the initial set up, is done by using the INF software. This can be achieved by either inputting commands that directly change the configuration or by editing a file and then 'executing' the file. In the case of the file, only the differences between the file and the running system are actioned. @section[X25 (1984)] Work is currently on hand to implement X25 (1984). Features will start to appear in early 1986 and there will be a comprehensive implementation by the end of 1986. The OSI CONS document has not been studied. @section[Academic Community Special Requirements] The TRAX system together with the X25 system has been designed and built with the specific criteria that it is easy to add 'user' modules to the system to tailor it for non standard requirements. However, Telematics state that they will not have enough spare effort and would not wish to take on 'specials' for the academic community. They stated that various software houses could do specials but they were not prepared to take prime contractor status for the work. The advantages and disadvantages of the community 'doing it itself' would need to be carefully weighed up. @section[Product History] There are now 250 to 300 systems installed world wide. The UK customers include BT with a 90 system in VASSCOM. The system will carry view data traffic. The major USA cistomers include Telecom General and Geisco. @Section[Maintenance Arrangements] The cost of hardware maintenance is approximately 70% of capital cost, the following figures were quoted for the standard configurations:- @begin[verbatim] 10 line @T{#}2,040 annually 18 line @T{#}2,112 " 48 line @T{#}5,940 " 100 line @T{#}9360 " @end[verbatim] With the addition of software maintenance, the cost runs to between 10 and 15% depending on types of licence in use on the systems. It is possible for the user to do 'first line' maintenance. @section[Company Information] The British Company is a wholly owned subsidiary of Telematic International Inc based in Fort Lauderdale, USA. The USA company designs and builds the hardware, although it is planned to manufacture in the UK during 1986. The British Company does the X.25 software development. The current UK company size is 30 - 35 people with a team of 9 working on X.25. @section[Confidentiality] Details of higher speed link plans. @section[Contact Name] @flushleft[D.N. Birss, Telematics International Ltd., Intec, Wade Road, Baskingstoke, Hampshire, RG24 0NE. Tel No. 0256 567385] @section[Summary]