Glossary - X

Glossary of Multics acronyms and terms. Entries by Tom Van Vleck ([THVV]) unless noted.

X.25

[MTB-607] Communications protocol supported by Multics in MR 10.0.

[DRV] X.25 was added to Multics in the early 1980s at the request of Canada in support of TRANSPAC. I did a deal with HIS Canada (Wally Halladay) to do X25 (which I wanted to do anyway) for a number of VIP7800 which CISL was desperate to have.

[THVV] Article: Multics Communications and Networking.

xforum, xmail

[BWS] "Executive" versions of the forum and mail commands. That is, they were menu-driven interfaces, slow and simple. Unbundled products released im MR 11.0. Info segment for xforum command

[DGRB] Developed at STC by Deryk Barkerand Mike Pandolfo.

XR

[BSG] Index Register. The 645 and 6180 each had eight of them. Containing only 18 bits, they cannot contain pointers when used in a Multics environment. See ABR.

XRAY

Jerry Grochow's tool for debugging 645 Multics. PDP-8/338 on the fifth floor of Tech Square, linked to a special GIOC channel by a 2400 baud phone line. The channel was in a send/receive loop, and the PDP8 sent address ranges to the GIOC, received the contents, and displayed them on its tube. Described in his 1969 FJCC paper "Real-time graphic display of time-sharing system operating characteristics."

XTS200

Honeywell product name for a "second generation SCOMP". Ran on the DPS6plus hardware. Received a B3 Orange Book rating.

XTS300

Wang Government Services (later known as Getronics (later known as DigitalNet (later known as BAE Systems))) inherited the XTS200 from Honeywell Federal Systems and ported it to a PC platform. It has a B3 rating like its predecessor.

XTS400

[Mike Focke] 2002-2003 outgrowth of the XTS300, produced by BAE Systems. PC based, uses Linux API/ABI compatible secure operating system STOP. Currently undergoing Common Criteria Evaluation.