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[Sankar Malladi <question219566@xxxxxxxxxxxxxxxxxxxxx>]

Question #219566 on rohc changed:
https://answers.launchpad.net/rohc/+question/219566

    Status: Answered => Open

Sankar Malladi is still having a problem:
yes i mistakenly copy pasted the bullet 3. my question is about RND =1
to RND =0  transition itself.

"For a/, the random IP-ID value is recorded as the new reference
by a call to ip_id_offset_set_ref() in the update_context() function
that is called once a packet is successfully decompressed.

For b/, if RND=0, then some bits of IP-ID offset are transmitted.
They must be used to compute the new IP-ID offset (see the
description of the W-LSB algorithm in RFC 3095). Once the new
IP-ID Offset is decoded, the new IP-ID value can be decoded from
the IP-ID offset and the decoded SN (see the description of the
Offset IP-ID algorithm in RFC 3095). The Offset IP-ID decoded at
step a/ is not used.

I hope that my explanations were clear enough. Do not hesitate to
ask additional questions if you need to."

Thanks again Barvaux: 
Here are my followup question:
1. For b/..can you point me to the code for reference?
2. If the offset IP-ID decoded at step a is not used then why do we need to compute or store the IP id offset when packet with RND bit set to 1 arrives?

Rgds
Sankar Malladi

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