Path: utzoo!attcan!uunet!mcsun!goya!david From: david@dit.upm.es (David Fernandez Cambronero) Newsgroups: comp.dcom.sys.cisco Subject: CISCO to X.25 switch connection Message-ID: Date: 13 Jul 90 17:01:44 GMT Sender: newsadm@goya.dit.upm.es Distribution: comp.dcom.sys.cisco Organization: Dept. Ingenieria de Sistemas Telematicos, UPM, Madrid, Spain. Lines: 82 Posting-Front-End: GNU Emacs 18.41.36 of Wed Jun 15 1988 on greco (berkeley-unix) Hello, Here at my University we are trying to connect a CISCO router to a X.25 switch at a speed of 64kbps. For that we are using the following hardware: * CAMTEC X.25 switch, with an X.21 interface. * A interface converter, from RS-449/422 to V.35 * CISCO router with a MCI controller and V.35 serial interface. * Two cables (??) to join the three equipments The general scheme follows: +--------+ X.21 to RS-449 +-----------+ V.35 +-------+ | Switch |----------------| Converter |---------------| CISCO | +--------+ +-----------+ +-------+ DTE DCE DTE ?? My questions are: 1) The CISCO has four possible hardware configurations for the serial interface: - inverted, internal clock - non-inverted, internal clock - inverted, external clock - non-inverted, external clock Does this mean that the CISCO can behave indifferently as an electrical DTE or DCE with internal or external clock? 2) We have the possibility of using an internal Tx clock in the X.25 switch. We would like to know which is the best configuration: - split clocks - CISCO putting the two clocks, or - Switch putting the two clocks and which cables to use (inverted, direct, etc..) 3) Do you know which V.35 cable must we use two conect two CISCOs between them? I hope not beeing so boring or asking too much but we are very interested in that connection. Any experiences, ideas or comments will be very appreciated. Thanks in advance, ------------------------------------------------------------------ David Fernandez tel: +34 1 5495700, +34 1 5495762 Dpto. Telematica x.367 E.T.S.I. Telecomunicacion Ciudad Universitaria fax: +34 1 2432077 E-28040 MADRID tlx: 47430 ETSIT E SPAIN E-mail: dfernandez@dit.upm.es Alternatives: dfernandez@goya.uucp dfernandez%dit.upm.es@uunet.uu.net X.400: C=es; ADMD=; PRMD=iris; O=upm; OU=dit; S=dfernandez; ------------------------------------------------------------------ -- ------------------------------------------------------------------ David Fernandez tel: +34 1 5495700, +34 1 5495762 Dpt. Telematica x.367 E.T.S.I. Telecomunicacion Ciudad Universitaria fax: +34 1 2432077 E-28040 MADRID tlx: 47430 ETSIT E SPAIN E-mail: dfernandez@dit.upm.es Alternatives: dfernandez@goya.uucp dfernandez%dit.upm.es@uunet.uu.net X.400: C=es; ADMD=; PRMD=iris; O=upm; OU=dit; S=dfernandez; ------------------------------------------------------------------