Subject: RE: <draft-ietf-ipfc-fibre-channel-03.txt>

From: Murali Rajagopal <[email-masked]>
Date: Mon, 23 Nov 1998 15:34:00 -0800

I believe the FC Header should also be added for the Minimum MTU size.
Therefore this number ought to be 92 bytes + 24 bytes FC Header = 116 bytes.

A similar number for the ARP Min MTU now becomes 52 bytes + 24 bytes = 76
bytes.

		-----Original Message-----
		From:	Murali Rajagopal 
		Sent:	Monday, November 23, 1998 2:30 PM
		To:	[email-masked]'
		Subject:	FW: <draft-ietf-ipfc-fibre-channel-03.txt>

		This messages form Mike Heard is being sent to the IPFC WG
for review and comment:
		Please note the changes in sizes suggested by Mike.

		-----Original Message-----
		From:	CM=[email-masked]
<mailto:CM=[email-masked]>
[mailto:CM=[email-masked]]
<mailto:[mailto:CM=[email-masked]]> 
		Sent:	Wednesday, October 28, 1998 2:10 PM
		To:	[email-masked]; <mailto:[email-masked];>
[email-masked]; <mailto:[email-masked];>  [email-masked]
<mailto:[email-masked]> 
		Subject:	<draft-ietf-ipfc-fibre-channel-03.txt>

		In <draft-ietf-ipfc-fibre-channel-03.txt> it is said

		   All implementations shall support at least an MTU of 44
bytes
		   representing the minimum IP packet size (20 bytes minimum
header ) +
		   LLC/SNAP header (8 bytes) + FC Network header (16 bytes).
The IP
		   level Maximum Transmission Unit  is 65280 as noted above.
		 
		The IPv4 spec (RFC 791), the Host Requirements document(RFC
1122), and the
		Router Requirements document (RFC 1812) all set the minimum
IP packet size
		which all implementations have to be able to send and
receive at 68 bytes,
		not 20.  This is the smallest size which allows a maximal IP
header (20 
		bytes
		fixed part plus up to 40 bytes of options) plus the minimal
amount of data
		(8 bytes) that an intermediate fragment can contain.

		This suggests that the minimal FC MTU size in the paragraph
I quoted should
		be 92 bytes, not 44 bytes.

		Cordially,

		Mike Heard