| 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 |
I'm trying to resolve a problem on a small ring of 1 DEFCN and 3 Cisco AGS+ (rel 8.3-3). The device counters are showing ring inits (transitions according to the Cisco) which are causing the customer concern even though the ring appears generally stable and there is no obvious user-level problem. I've put an analyser on the ring (the Sniffer with the FDDI card) and set it up to capture _all_ traffic except voids (ring purging is enabled on our con) and to trigger (and save a snapshot of the data) on receipt of any claim frame. I've proved this trigger/snapshot works - it's probably the best feature of the box because it re-starts the capture after the snapshot so you can collect multiple snapshots - BUT for the last 2 nights all the 4 boxes on the ring have logged 2 inits (remote inits on our concentrator) _without_ triggering my analyser ! So, the question is - how can our concentrator believe there has been a ring initialisation without there having been a claim frame on the ring ? NB1, the way I detect a claim is by looking for a FC field of C3. Am I correct in thinking there is no other possible claim allowed (ie is 83 a valid claim, implying a box on the ring is using a 16 bit address for the claim). NB2, I've set the Cisco parameters so the concentrator wins the claim. If there is a '16 bit address' claim, would our concentrator reply using 48 bit addresses for it's own claim? Thanks for any info, Steve
| T.R | Title | User | Personal Name | Date | Lines |
|---|---|---|---|---|---|
| 838.1 | KONING::KONING | Paul Koning, A-13683 | Thu Jan 21 1993 17:48 | 6 | |
83 would be a valid, though unlikely, claim. Whether our MAC would respond with C3 depends on the claim; if the Tbid in the 16-bit claim is for a shorter TTRT than the one set in the concentrator (8 ms by default) then the 16-bit claim would simply be repeated. paul | |||||
| 838.2 | COMICS::WOODWARD | Smile! | Mon Jan 25 1993 03:48 | 10 | |
RE -.1 Can I go to the next step and assume that, if our concentrator will be the claim winner, it will always use 48 bit addresses regardless of the claim it receives? Plus, any comment on how 'inits' can be logged without a claim. Thanks, Steve | |||||
| 838.3 | KONING::KONING | Paul Koning, A-13683 | Mon Jan 25 1993 11:15 | 10 | |
All our products use 48 bit addresses exclusively. The rule is that in the claim process you either repeat the received claim, or send your own claim with your own address. You do the former if the received claim takes precedence over your own according to the claim rules. Apart from being one of the tie breakers in comparing claims, the address length has no effect on the claim process. paul | |||||