draft-ietf-ipsec-esp-v3-01.txt: extended sequence number

[Jun-ichiro itojun Hagino <itojun@iijlab.net>]

	I've got some question regarding to extended sequence number documented
	in ESPv3 (01 draft).  clarification is appreciated.

	In section 2.2.1, it is mentioned that higher 32bit of extended
	sequence number is included in ICV.  If this is the case, I guess
	the use of extended sequence number MUST be negotiated by SA management
	protocol (instead of "SHOULD" in 01) as the use of extended sequence
	number changes the wire packet format used for ICV computation.
	if one end uses extended sequence number and the other doesn't, they
	will compute ICV differently.

	packet diagram in section 2 seems a little bit confusing with respect
	to extended sequence number case (sequence number in the diagram has
	only 32bits).

itojun