giebelhaus@hi-csc.UUCP (Timothy R. Giebelhaus) (09/13/87)
Does anyone know of a good way of telling Ethernet transceiver
cables apart. Reading the spicifications, I can see how
version 1, version 2, and 802.3 are different, but I have a
pile of cables and I need to identify them. It would be best
if I could do this without tearing the cables apart.
Anyone have any ideas?
Thanks.
UUCP: {uunet, ihnp4!umn-cs}!hi-csc!giebelhaus
Arpa: Giebelhaus@HI-MULTICS.ARPAron@topaz.rutgers.edu (Ron Natalie) (09/14/87)
It was my impression that 802.3 and Version 2 cables were identical and Version 1 cables differ only in conductor size. -Ron
hobson@aramis.rutgers.edu (Kevin Hobson) (09/14/87)
From Cabletron Systems literature:
V1.0 V2.0 IEEE 802.3
------------------------------------------------------------------------------
Transceiver (3)22 AWG pairs (4)20 AWG pairs (4)20 AWG pairs
Cable pairs Inner & Outer shield Inner & Outer shield
(1)20 AWG common at backshell isolated from each
Inner & Outer and pin 1 other
shield common Other shield at
at backshell backshell inside
and pin 1 at pin 4
Indented Male
connector for better
electrical connection
------------------------------------------------------------------------------
If I see, on the male end of cable, pin 4, I assume it IEEE 802.3
transceiver cable. Otherwise, I assume version 1 or 2 cable. I use a
Cabletron LAN-MD if I not sure and I want to test the cable integrity
without opening the hoods.
No, I do not work for Cabletron but a satisfied customer.
--
- Kevin Hobson
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- Rutgers University, New Brunswick, NJ 08903 (201) 932-2260
(201) 932-5027
(201) 932-2492carey@uiucdcsb.cs.uiuc.edu (09/14/87)
What are the differences? We have used all sorts of generations of cables with all the different types of transceivers, and have never found a problem which could be attributed to a compatibility mismatch of cables and transceivers.
bob@uhmanoa.UUCP (Bob Cunningham) (09/14/87)
Apropos of transceiver cable questions: In making up one's own, what is the proper cable to use? Belden 9891 or 9892? Bob Cunningham bob@loihi.hig.hawaii.edu or ...nosc!humu!uhmanoa!loihi!bob -- Bob Cunningham bob@hig.hawaii.edu
steve@gec-mi-at.co.uk (Steve Lademann) (10/12/87)
We have recently experienced some problems with a BICC/ISOLAN fan-out unit (DELNI equivalent). We had a 15 metre, unterminated transceiver cable attached to said fan-out unit which went close to some high frequency electrical noise (well, an LSI-11/73 computer system actually - the DEQNA which the cable was originally attached to was having the anti-hang ECO applied to it, but that's another story). At odd times, the fan-out unit sprayed random garbage onto the Ethernet, causing Havoc. The Ethernet on this site is fairly extensive, so finding the problem was not easy. ISOLAN/BICC told us that the problem was due to the cable being Series 2 not 802.3. However, substituting a DELNI for the ISOLAN box cured the problem. Now, the net effect is that I've got the distinct impression that I've had the wool pulled over my eyes. Any netlander care to comment? |Steve Lademann |Phone: 44 727 59292 x326 | |Marconi Instruments Ltd|UUCP : ...mcvax!ukc!hrc63!miduet!steve | |St. Albans AL4 0JN |NRS : steve@uk.co.gec-mi-at | |Herts. UK | "disclaimers.all"
mwn@ufcsg.cis.ufl.EDU (Michael Nora) (10/15/87)
In article <766@gec-mi-at.co.uk>, steve@gec-mi-at.co.uk (Steve Lademann) writes > At odd times, the fan-out > unit sprayed random garbage onto the Ethernet, causing Havoc. The Ethernet > on this site is fairly extensive, so finding the problem was not easy. > ISOLAN/BICC told us that the problem was due to the cable being Series 2 > not 802.3. However, substituting a DELNI for the ISOLAN box cured the problem > > Now, the net effect is that I've got the distinct impression that I've had > the wool pulled over my eyes. Any netlander care to comment? There are differences in the cables. We have Chipcom Broadband Ethernet modems in use on this campus, and the following is excerpted from Technical Tip 87-003 issued by Chipcom Corp. There are a few subtle differences in the AUI transceiver cables in use today. These differences occurred because there are three Ethernet standards, V1.0, V2.0, and 802.3. 1. In version 802.3, all shields of the individual signal and power pairs are connected to pin 4. The overall AUI cable shield is connected to the AUI connector shell to provide a cable ground. Pin 1 is not used. 2. In version 2.0, all shields are connected to pin 1 and the AUI connector shell. Pin 4 is not used. Most Ethernet cables are built this way. 3. In version 1.0, shielding of individual signal or power pairs was not required since most controllers and transceivers were DC-coupled. The overall AUI cable shield provided for shielding and grounding and was connected to pin 1 and the AUI connector shell. In practice, most Ethernet V1.0 equipment used version 2.0 cables due to cross talk problems created by the lack of individual shielding for the pairs. Also, since the 802.3 AUI cables provide an isolated ground shield from the signal and power pairs shields, these cables provide additional noise immunity in noisy operating environments. Maybe the ISOLAN equipment you have requires the version 802.3 cable. All of the DEC equipment I've seen used the version 2.0 cables. This may be why the DELNI works and the ISOLAN doesn't. Open the shells on your transceiver cables, and if they are grounded to pin 1, try moving them to pin 4 and see if that cures your problem. Hope this helps out. -- ^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^ Michael Nora Internet: mwn@beach.cis.ufl.edu University of Florida UUCP: ...{ihnp4,rutgers}!codas!ufcsv!ufcsg!mwn v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v^v
mam@philabs.Philips.Com (Mark A. Maxwell) (10/19/87)
In article <766@gec-mi-at.co.uk> steve@gec-mi-at.co.uk (Steve Lademann) writes: >We have recently experienced some problems with a BICC/ISOLAN fan-out >unit (DELNI equivalent). We had a 15 metre, unterminated transceiver cable >attached to said fan-out unit which went close to some high frequency >electrical noise (well, an LSI-11/73 computer system actually - the > The Ethernet >on this site is fairly extensive, so finding the problem > was not easy. >ISOLAN/BICC told us that the problem was due to the cable being Series 2 >not 802.3. However, substituting a DELNI for the ISOLAN box cured the problem. > >Now, the net effect is that I've got the distinct impression that I've had >the wool pulled over my eyes. Any netlander care to comment? > >|Steve Lademann |Phone: 44 727 59292 x326 | >|Marconi Instruments Ltd|UUCP : ...mcvax!ukc!hrc63!miduet!steve | We also have a highly populated backbone with an odd assortment of transeivers and MTU's. The BICC type mentioned above are in use and were purchase because the DELNI units had caused some connectivity timeout problems. I have noticed that when attached to a Bridge IB/2 internetwork bridge the BICC Fanouts do some times cause packets to bounce around or some how generate broadcast packets on other systems. I say its a toss up.. It seems that they both have their own short comings depending on a lot of variables, so in the end it pays to have both types around an used which ever box seems to work in a given application. + Mark -- itzzall4phun- Olin Mann {ihnp4,uunet}!philabs!mam philips laboratories * * * * * * Spazzze out in a moon-age day dream ..........Oh Yea! * * * * * *
hedrick@topaz.rutgers.edu (Charles Hedrick) (10/21/87)
We use TCL multiport boxes quite extensively. We have never had any problems due to them. They are a bit bigger than some of the newer boxes, and maybe slightly more expensive, but we have our suspicions that they are also more solid.