IPv6 message size with OpenBSD. Is it a must that IPv6 packet length will be a multiply of 8?

["sasson, shuki" <sasson_shuki@emc.com>]

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Hi all, observing the code of OpenBSD and also trying it, I see that the
code takes care that the IPv6 packet length will be a multiplication of 8.
I read the IPv6 RFC 2460 and I didn't see ant restriction there that
suggests that the IPv6 packet length should be a multiplication of 8.
Does any of you have an idea why is that?
Can I safely send IPv6 packet with a length that is not a multiplication of
8 and make a better use of the MTU?

Example:: In a system where the MTU is 1500 the Ethernet packet sent in
OpenBSD systems are 1510 instead of 1514 thus a loss of additional 4 bytes
as a result.

Your help is appreciated,

Shuki Sasson
Principal Engineer, Network Storage Group
	EMC˛  		
where information lives

Phone: 508 305 8515
FaxNo: 508 435 8901
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Email:  sasson_shuki@emc.com