RFC5225 IP-ID with co_common and Random behavior and tos_tc changes

Hello everybody,

if the ip-id has a random behavior, it is sent in the irregular chain
as defined in ipv4() encoding method and ipv4_innermost_irregular format.
This encoding method has a DEFAULT section, which also defines that
tos_tc is encoded static (and other).
If I understand den ROHC FN right, the format
ipv4_innermost_irregular could not be used,
if the tos_tc could not encoded by the static encoding method.
But then I can not use co_common format to transmit tos_tc changes,
because the ip_id is not included in co_common if the behavior is random.
Is this correct?

Regards,
Klaus

-- 
Klaus Warnke		[email protected]
http://www.acticom.de
Tel +49-30-4849.6891

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