Subject: question about TCP checksums

From: "Eric A. Hall" <[email-masked]>
Date: Tue, 20 Oct 1998 09:14:35 -0700

Hi,

I hope this is the right place to ask this question.

Various documents seem to be at odds with each other regarding the
proper behavior for responding to a TCP segment that has an invalid
checksum. Although STD 7 states that the segment should be discarded, it
doesn't state what should happen next.

Some material suggests that the recipient shouldn't do anything, waiting
for the sender to timeout and retransmit. Conversely, other materials
suggest sending an ACK for the last successfully-received segment.
Either method would seem to work, with the benefit depending on the
exact scenario.

The question is: what's the position of the group as to which method is
the enforcable STANDARD method?

Thanks

-- 
Eric A. Hall                                            [email-masked]
+1-650-685-0557                                    http://www.ehsco.com

---

From: Mohit Aron <[email-masked]>
Date: Tue, 20 Oct 1998 11:27:39 -0500 (CDT)

> Either method would seem to work, with the benefit depending on the

If the checksumming fails, then the recipient cannot be sure of which
connection the TCP segment belongs to. The appropriate behavior then should
be not to do anything.

- Mohit Aron
  [email-masked]