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New Member

bridging token to ethernet and vice versa


has somebody experiment the interconnexion beetween ethernet and token ring with MADGE 's bridge DESKTREAM ?

The Destream is a token bridge (24 toekn ring port) with an ethernet Uplink port;

The existing network is the token ring with 2 catalyst 3920 (version SW Rev 3.0(5)) at the bacbone, and the new network is the cisco ethernet network (catalyt 4006).

For the migration period , we need to interconnect these two networks.

0n the Destream , ther's source rounting (SR) and SRT;

1st question: can or how the destream convert the frame with 4096 bytes of MTU to the ethernet frame of 1500 bytes;

2nd question: the pb with the encapsulation on token ring and the ethernet "type " in the ethernet frame.

Is the Destream can answer to this interconnexion ?

I'm ok that generally, we use the router and not the bridge.

thank for your help;

  • Other Network Infrastructure Subjects

Re: bridging token to ethernet and vice versa

I cant speak to the capabilites of the Madge device. However, Cisco routers do support source route translational bridging, which in effect does media translation. One quiestion would be, is there any routing in the network right now ? If, for example the 3920's were on subnet a, and the 4006 on subnet b,

a router with both token and ethernet interfaces would do the job.

here is a link to the SRT stuff. Also, depending on your applications, Data Link Switching might be a player.

New Member

Re: bridging token to ethernet and vice versa

Why do you need a migration period? The network is small enough to replace overnight with a bit of effort and planning.

In any case I would advise against SRT if you can possibly avoid it. Why do you need to bridge the two networks, rather than route between them? This would be preferable as long as you are not running any non-routable protocols.