kemp@uiatma.atmos.uiuc.edu (John Kemp) (11/10/90)
This is a warning if you are planning on installing an Unshielded
Twisted Pair (UTP) repeater and using UTP-THIN transceivers to extend
your network...
UTP-THIN has problems with existing platforms !!!
In particular, we have a Vaxstation 2000 in a Local Area Vaxcluster
running the DECNET protocol that repeatedly drops and reestablish
connections for up to a minute.
And we have seen an IBM RS/6000 320 come up and subsequently lose it's
connection network after a number of hours. The connection is never
reestablished.
Both machines worked fine on AUI-THIN repeater segments. Putting the
IBM on an AUI-UTP transceiver appears to have corrected the problem.
It should also be noted that two MacII's were on the same segment with
the IBM when UTP-thin was being used. On the Vaxstation, it was the
only station on the net. Various cable lengths were tried. Cable
continuity was checked in both cases.
Moral: don't count on UTP-THIN transceivers!
If you do, you had damn well better try before you buy, and even then,
if you add a different type of machine to the segment you may be
hosed. Our system was a Plexnet repeater with Plexit 10baseT UTP-THIN
transceivers. (Your mileage may vary. I am only speaking from
painful experience.)
You have been warned.
john kemp internet - kemp@uiatma.atmos.uiuc.edu decnet - uiatmb::kemp
univ of illinois bitnet - {uunet,convex}
dept of atmos sci !uiucuxc!uiatma!kemp
105 s gregory ave phone - (217) 333-6881
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