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From: mckee@MITRE.ARPA.UUCP
Newsgroups: mod.protocols.tcp-ip
Subject: Layer 2 muxing on ISDN
Message-ID: <8704041540.AA11587@mitre.ARPA>
Date: Sat, 4-Apr-87 10:40:32 EST
Article-I.D.: mitre.8704041540.AA11587
Posted: Sat Apr  4 10:40:32 1987
Date-Received: Sun, 5-Apr-87 10:54:23 EST
References: <[A.ISI.EDU].1-Apr-87.21:28:17.CERF>
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The proposed Frame Relay service of ISDN does do layer 2 multiplexing.
In LAPD, there is a 2 byte address containing a 6 bit SAPI and a 7 bit TEI
(Terminal Equipment Identifier).  These 2 fields are combined into a
13 bit DLCI (Data Link Connection Identifier) which would be handled
similarly to the LCN in X.25.  It would be mapped and set in each node as a
frame progressed through the network.  Then a new CRC would be calculated
and inserted.
*
*        Steve