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Re: [Question #219566]: “How to calcualte the ip_id on decompressor side when RND bit toggles from 1 to 0”.

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From: Sankar Malladi <question219566@xxxxxxxxxxxxxxxxxxxxx>
Date: Sun, 20 Jan 2013 17:01:12 -0000
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Question #219566 on rohc changed:
https://answers.launchpad.net/rohc/+question/219566

Sankar Malladi posted a new comment:
HI Didier
Thanks again. Finally all my confusion boils down to one of the below conclusions either 1 or 2. pls confirm. 

1. The offset IP-ID encoding in RFC 3095 section 4.5.5
"When receiving a compressed packet m, the decompressor calculates
      Offset_ref = ID_ref - SN_ref, where ID_ref and SN_ref are the
      values of IP-ID and RTP SN in the reference header, respectively."

so here ID_ref is nothing but the IP ID that decompresser decoded successfully in the previous packet? 
but then it conflicts with the statement  "The Offset IP-ID decoded at step a/ is not used."

2. [d_generic.c:7193 parse_extension3()] 16 bits of outer IP-ID in EXT3 = 0x136f
Does this mean, the IP ID has to be sent in the EXT 3 FIELDs when RND changed to 0 so that we donot need to look at the ip id decompressor decoded in prev packet?

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