dirish@esunix.UUCP (Dudly Irish) (11/05/88)
We have a large LAN at our site partitioned into 9 LANs by DEC bridges. Each of the buildings has both thick wire and thin wire segments. We also have a large number of vendors with (at last count) 23 odd protocals. We also have a LAN traffic Monitor from DEC and it is in reference to this that I post. This monitor will show us the number of CRC an oversize packets it sees on whatever section of the network it is connected to. And we see on the order of %0.005 packets have one of these errors. Now this amounts to a very small number of packets in relation to traffic, but I can't help but wonder if these really should be zero. So would the people out there will similar sized networks please post your experiences? Dudley Irish Evans & Sutherland
eshop@saturn.ucsc.edu (Jim Warner) (11/06/88)
In article <1052@esunix.UUCP> dirish@esunix.UUCP (Dudly Irish) writes: >We have a large LAN at our site partitioned into 9 LANs by DEC bridges. ... >And we see on the order of %0.005 packets have one of these errors. ... >So would the people out there will similar sized networks please post your >experiences? You don't say how large the segments between the bridges are. That's significant because these errors aren't propagated through LanBridges. Your error rates don't seem at all out of line. You should be aware that when the error rate is this low that the point of attachement of the monitor on the LAN will probably affect the results. Looking at a dual interface Sun server connected to two ethernets, I get: total packets packets with rcvd errors 903607 33 Single segment sun-only net 2474071 13 Multi-segment four building backbone The multi-segment backbone uses repeaters which *DO* propagate damaged packets. I start getting interested when the bad packet rate climbs to about 0.05 %. I get concerned when it climbs above 0.2 %. I could make these error rates much lower by dumping lots of money into improved network hardware. But I don't see that it would be worth it. jim warner U.C. Santa Cruz