Re: [Roll] CmprI and CmprE in SRH

Jonathan Hui <jonhui@cisco.com> Thu, 22 December 2011 02:29 UTC

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From: Jonathan Hui <jonhui@cisco.com>
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Date: Wed, 21 Dec 2011 18:29:12 -0800
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To: Mukul Goyal <mukul@uwm.edu>
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Subject: Re: [Roll] CmprI and CmprE in SRH
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On Dec 21, 2011, at 5:15 PM, Mukul Goyal wrote:

> I think this was probably discussed earlier in your discussions with area director. But I was wondering if you could clarify again why do we need separate CmprI and CmprE? I think the last element in the Address vector specifies the ultimate destination (reachable using SRH) of the packet. Why would that destination need a separate number of elided prefix octets?


In the case that a RPL routing domain is used as a transit network.  It is important to support the case where the SRH only specifies a subset of the path (see the 3 different cases in the image on page 5 of the draft.

--
Jonathan Hui