Bob in Phx said:
The cables are most likely type/cat 1. With a token ring type A connector.
They are very obsolete.
Here is a web page with the various types of type 1 cable ends.
http://www.pacificcable.com/TokenRing.htm
Note that type/cat 1 is shielded twisted pair and in fact is much better
then Cat 5 cable as it is shielded. If memory serves correctly, the max
length is 1500 feet for token ring, on this type cable.
bob in phx
Well partially right. After the 1984 Judge Green legal decision (breaking
up AT&T - so AT&T could go into the computer business to compete against
IBM)
IBM developed a "Type cabling system" in an attempt to standardize the data
cabling infrastructures -- for the vendor (mfg) specific & proprietary
cabling solutions (e.g. Datapoint had ARCnet with RG-62/U 93 ohm cable;
Ethernet has 10-Base-2 and 10-Base-5 used 50 ohm coax cables; Proteon ProNet
4 & 10 which used shielded twisted pair; AT&T had StarLAN; Novell had
StarNet)
I installed Type 1 cabling during 1980s and it was a bear to retrofit into
existing buildings. Improper termination at the patch panel caused most of
the problems -- cable installers hated the stuff.
AT&T desired to reuse existing Bell installed unshielded twisted pair
cabling. I believe that Anixter was the first with AT&T to developed the
"Category designations (Cat 1; Cat 2; Cat 3). I once had all of this PHY
specification documentation from 1970s and 1980s - but finally pitched much
of it in late 1990s.
gb