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

From: Murali Rajagopal <[email-masked]>
Date: Mon, 23 Nov 1998 14:30:27 -0800

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.

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Sent:	Wednesday, October 28, 1998 2:10 PM
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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