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ROHC CT issues. Carsten Bormann, 2003-07-17. The RFC 3095 architecture. Header compression is on a channel Multiple compression contexts are multiplexed via a CID (compression context ID) HC state is L2 state In a bridged system, lives on AP, not AR
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ROHC CT issues Carsten Bormann, 2003-07-17 cabo@tzi.org
The RFC 3095 architecture • Header compression is on a channel • Multiple compression contexts are multiplexed via a CID (compression context ID) • HC state is L2 state • In a bridged system, lives on AP, not AR • There are multiple profiles (RTP, TCP, …) • Some even have special state at L2 (LLA) cabo@tzi.org
Implications (1) • Handover creates a new channel • Normally, negotiation required! • Some context fields may need to change (e.g., IP address) • These are profile specific • Context was active before transfer • Race conditions possible! cabo@tzi.org
Implications (2) • How does MN know that CT was done? • And what CT parameters were used, if any? • What is the CID mapping on nAR? • Any other interesting channel parameters? • CT operation must be part of HC profile • Quite similar to ROHC context replication:draft-ietf-rohc-context-replication-00.txt cabo@tzi.org