I think you are close but here are my thoughts off the top of my noodle, the source ring would be the TRCRF as you say. I think the bridge number just needs to be the same on both routers and is not associated with the BRF. lastly the target ring is the number you choose via the source-ring bridge-group command on the router.
FWIW Dave Chuck Larrieu wrote: > > for whatever reason, my mind has been ensnared with thoughts of the Cat 3920 > token ring switch and various implications. > I want to run a couple of concepts through the list, just to check that my > understanding is correct. > > So, because of the nature of token ring, one has to do some jiggering to do > token ring switching. IBM or whomever, in their wisdom, came up with the > following model: > > in general - token ring bridging works on the ringbridgering model > > port - into which plugs some physical token ring device, which may be a > router, an end station, or a token ring shared media device like a mau. ( > much the way one might plug ethernet hubs into switch ports ) A port can > connect only to one TrCRF ( see next layer ) > > TrCRF - token ring concentrator ring function. This is the logical virtual > ring. more than one physical port can connect to a TrCRF, which in turn can > connect to only one TrBRF ( see next layer ) > > TrBRF - token ring bridge relay function. As implied by the name, the TrBRF > bridges between the virtual rings. The TrBRF is also the "VLAN". therefore > routing must occur between stations ultimately connected through different > TrBRF's. > > This is what I am not sure about. Per the 3920 simulator I am using > different BRF's can be on the same subnet. I don't have access to a real > device to see if this is true in the real world. > > Also, there is a decent explaination of token ring vlans in the Kennedy > Clark book Cisco Lan Switching. However, Clark seems to emphasize source > route switching, and the advantages in terms of explorers, rather than > straight ( if there is such a thing in token ring ) switching, and the > advantages to end stations. > > One of the things I am getting around to in this post is DLSw over a token > ring switch. DLSw is configured on a cisco router using bridging and a > virtual ring which is created across a TCP network between peers. > > router ----virtual_ring------router > | | > TR_port TR_port > > with the configuration of the TR port using the source-bridge set of > commands source-bridge source-ring-number bridge-number target-ring-number > > If I wanted to run DLSw across a 3920, then on my router ( whose token ring > port is plugged into a 3920 ) I would use the source-bridge > source-ring-number bridge-number target-ring-number comand. The source ring > would be identical to the TrCRF ring, the bridge would be the TrBRF, and the > target ring would be the DLSw virtual ring, as confgured under DLSw. Is that > correct? > > Sorry if this is a bit disjointed. I'm working from home today and the > family seem to think that if they are on vacation, so am I. > > Any thoughts would be appreciated. > > Chuck -- David Madland Sr. Network Engineer CCIE# 2016 Qwest Communications Int. Inc. [EMAIL PROTECTED] 612-664-3367 "Emotion should reflect reason not guide it" Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=30575&t=30566 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
