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Re: IP bridging between Eth and TR posted 03/20/1999
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>The answer is quite simple, there is no way to know what is or is not an
>address within the data portion of the packet, therefore no form of
>translational, concurrent, integrated or transparent bridging will help you.
>
>Of course. I was always of the opinion that token ring was beyond help.
>
>Jim

I used to think this, until it was pointed out to me that ARP does contain
a protocol type field that lets some implementations know what type is in
the data field, so translations can be set up properly.  I certainly
wouldn't assume a specific interface will do this without extensive testing.

I'd be curious, in fact, which Cisco configurations are smart enough to do
this.

>
>At 10:36 AM 2/22/99 -0000, Jose L. Carles wrote:
>>Hi, pals
>>
>>    I'm posting this mail because I'm trying to sort out  a 'little
>problem'. This question has been posted to the cisco newsgroup last week,
>but I think you could help me (and I guess this is a really interesting
>question).
>>
>>    What I need to do is to bridge IP traffic between an Ethernet and a
>TokenRing segments.
>>
>>    I know what you are going to tell me ... it won't work. The bridge can
>always translate the MAC addresses contained into the packet headers, but
>some protocolos, like ARP, carry MAC addresses in the data field of the
>packet (where the bridge won't inspect).
>>
>>    After a lot of reading, and thinking, I have arrived to IRB
>(Integrated Routing and Bridging) but I have no tested it yet. Does anybody
>think it could help at this?
>>
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