| Title: | FDDI - The Next Generation |
| Moderator: | NETCAD::STEFANI |
| Created: | Thu Apr 27 1989 |
| Last Modified: | Thu Jun 05 1997 |
| Last Successful Update: | Fri Jun 06 1997 |
| Number of topics: | 2259 |
| Total number of notes: | 8590 |
Westinghouse is evaluating FDDI products, they specifically asked the
sales rep about setting TTRT to 25-50 ms - said that it crashed the
ring using it with previous DEC products.
From the Email from Sales...
Problem with DECconcentrators (perception):
Can't set TTRT (target token rotation time)
Need 25-50 ms
Attempt to do this on previous DEC product crashed
- the ring.
Evaluation Criteria:
Granularity (number of port selections)
Media types supported
DUAL HOMING*
Redundancy features
Packaging in general(?)
My guess is that it may be a configuration/topology/feature and
interoperation with other products that caused the problem (i.e. we
tried to negotiate it but somebody didn't do it in a standard way so
the ring crashed...?) But not being an FDDI bit twiddler I didn't
know.
Any thoughts on this?
thanks!
j
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 1891.1 | NETCAD::STEFANI | Machines to humanize | Wed Dec 06 1995 10:22 | 9 | |
>> Problem with DECconcentrators (perception):
>> Can't set TTRT (target token rotation time)
I'm certain that this is not an issue with any of our DEChub 900-based
FDDI concentrators and bridges. HUBwatch is fairly powerful for the
FDDI gear and offers all sorts of knobs to turn, including modifying
MACTReq (requested TTRT).
/l
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| 1891.2 | NETCAD::B_CRONIN | Wed Dec 06 1995 11:51 | 22 | ||
Let me be a pain.....
Do we know specifically what products are involved? Foe
instance, is it one DECcon 500, or is it a DEC adapter
that has a problem. I seem to remember Westinghouse as
a "special" adapter customer.
Does crash mean fails to come back to life, or does it mean
the ring claimed?
I haven't heard of this problem before, but there's always a
first time. In general, we don't see people changing this value,
so, maybe it is a first time.
Offhand, I can't think of a reason why this can't be done. I'm not
sure doing it is necessary, but that's a different question.
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