keith@cecil.UUCP (keith gorlen) (10/20/84)
We are running an Ethernet with three segments connected via DEREP repeaters. When we first installed the network, we had the two DEREPs driving the "rib" segments connected to a DELNI which was in turn connected to an H4000 on the "backbone" segment. Stations (in this case Bridge Communications CS/100s) on the backbone could talk to stations on the ribs, but stations on different ribs (i.e., stations with both repeaters between them) could not. Removing the DELNI and connecting the DEREPs directly to H4000s on the backbone solved the problem. Bridge claims that the DELNI didn't work because it counts as 1/2 a repeater, but DEC's Ethernet catalog implies that a DELNI counts as just 5m of transceiver cable. Our DEC salesperson claims that the DELNI doesn't behave exactly like an H4000 (something about not handling collisions) and does not work with DEREPs for that reason, but will work with a compatible station. The salesperson doesn't remember the source of this information, the CS/100s are not compatible with the DELNIs so we can't do the obvious experiment just yet, and we are curious about what's going on. Anyone know? keith