Suresh,

First, one simple comment.

1. In section 1 of your draft you say 

[may need to look at the transport layer header fields...]

Change "transport layer header" to "upper layer header" because 

(a) You must use language consistent with RFC 2460.
(b) Use of transport layer is incorrect because ICMP is a layer 3
protocol that is also upper layer for IPv6 Extended Header (EH) while
the transport layer is layer 4.

On to more critical issues. 

2. I and Wes don't agree at all with bullet 2 in section 4 (Future work)
of this draft that says:

[Extension headers must be processed in any order they appear]

Hop-by-hop option is processed by every intermediate router and such
router's fast path silicon is usually a hardware engine that parses the
first x bytes of the Extended header (EH) where x can be say, 64 bytes.
I suspect that was the design theme when folks wrote RFC 2460 and made
sure hop-by-hop was always the first EH. Also, as reviewers of your
draft we still keep in mind that hop-by-hop hasn't been deprecated. 

Further, section 4.1 of RFC 2460 also defines a specific sequence of
EH's. We want your draft to still comply to RFC 2460 in this regard -
comply with section 4.1 of RFC 2460 and preserve this section's EH
Order. Further this section from RFC 2460 says:

[If and when other extension headers are defined, their ordering
constraints relative to the above listed headers must be specified].

This constraint cannot be dispensed with without very careful thought.

3. RFC 2460 clearly says in section 4 that EH's are not processed by
intermediate nodes unless the EH is a hop-by-hop EH. Since your draft
ignores this rule of RFC 2460, it's up to the IPv6 community to first
agree to such a change to RFC 2460 before looking at your draft.

Hemant & Wes
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