The IP over ATM Mailing List Archive by date

[George Swallow <swallow@cisco.com>]

>i don't remember how AAL3/4 implements MID allocation, but vci allocation
>protocol could be something similar.

I've only seen the scheme used for SMDS/CBDS.  This assumes taht the
links are all point to point.  The MIDs serve no purpose than to
distinguish the cells of one packet from the next, so the assignment
of MIDs can be arbitrary. The destination address needed is in the
packet itself.  It is this address that the SMDS server uses for its
routing decision.  Once routed the rest of the cells of that packet
(i.e. those with the same MID) are routed to the same VPI/VCI/MID.

The sending end just uses MIDs as it likes.  All cells on a MID must
go to the same dstination.  When a MID ceases to be used, it may be
reused for a different destination after some timeout period.

This mechanism doesn't solve any of the problems of associating a
unique ID with an endpoint of a multicast call.  I'm afraid we'll have
to invent something.

...George