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Termination of X25/X29 Service in December 1996

  John Ogilvie and Francois Fluckiger CN/CS

Please note that all the CERN X25/X29 services will be terminated at the end of December 96.

For more than 15 years the X.25 service has provided access between CERN and the outside world. (X.25 refers to the name of a telecommunications standard issued in 1976 and adopted by telecommunications operators to support their first switched data service. Sometimes called the "telephone of the computers", it was actually modeled on the plain old telephone service, allowing computers or their users to set up calls using a telephone-like numbering scheme.)

CERN connected first in 1981 to TELEPAC, the Public Swiss PTT X.25 service. Access to and from computers connected to CERNET, the general-purpose high-speed LAN became possible through a home-made CERNET-X.25 gateway. Together with the EARN network (set up in 1984), the X.25 service constituted the major means for CERN external communications with leased lines access to most CERN member countries.

From 1990, with the opening of CERN external TCP/IP services, the X25 service traffic rapidly declined.

As the hardware is now more than 10 years old, no longer supported and the traffic negligible, it was felt the time was ripe to terminate this venerable service. After INDEX, CERNET, and EARN, this is the last CERN networking dinosaur of the '80s to disappear.