| 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 |
Note 1374 in this conference refers to a balun. Is there any info about the manufacturer, etc. ? We have a situation where an IBM AIX system with SDDI (Shielded Copper FDDI with DB9) needs to communicate with a DECconcentrator 900TH 16 port Concentrator via one of its RJ45 UTP port. Customer has made his own cable - DB9 to RJ45 by following the pin-outs in the IBM and DEC manuals. The two systems do not communicate and the RJ45 port LED on the DC900TH does not come on. By other testing we know the IBM end is good and the DC900TH RJ45 end is good. Note 1374 talks about a 100/150 ohms balun. Alphonse
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 1792.1 | first, ask some basic questions | NETCAD::MELARAGNI | Tue Aug 29 1995 08:49 | 17 | |
Before we get to the balun topic, a few questions:
1) Is the AIX supporting TP-PMD or the older "gang of five"
non-standard interface? TP-PMD and gang of five will not interoperate.
2) What's the distance of the shielded cable? If it's longer than
about 200m you may have a problem. What's the loss of the cable
measured at 16MHz? This is a common measurement for IBM cabling
systems, so the customer site should have this info.
3) Did the customer pin the adapter cable out correctly, including
any necessary cross-overs?
As for vendors of baluns, you may want to try Black Box. They are on
the web: http://www.blackbox.com/
bill
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| 1792.2 | SDDI was another pre-standard copper fddi | NETCAD::B_CRONIN | Thu Aug 31 1995 18:10 | 9 | |
There was another pre-standard STP version of FDDI on STP cable
that IBM did, and they called it SDDI. If that's what they have, it
won't work with anything we've built.
If they are still calling their stuff SDDI, then follow Bill's
questions in .1
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