Subject: [Simple] MSRP: DSN lifetime open issue

From: Ben Campbell <[email-masked]>
Date: Thu, 15 Apr 2004 10:30:51 -0500

One open issue concerning MSRP usage of DSN that I would like to close 
on is, what happens to DSNs after a session is torn down?

Example:

A          R           B
SEND------->
<---------OK
            SEND----X
<---session teardown--->
<-----REPORT

In this example, A sends a message to B via relay R. The A-->R hop works 
fine. The R->B hop failes, due to a tcp error. For the sake of argument, 
consider this to be a worst case TCP error where the TCP stack has to 
work through the entire retransmission sequence before it gives up, that 
is, a non-trivial amount of time passes.

A and B tear down the session. But since R is not session stateful, it 
does not know about this.

So, the question becomes, what happens to outstanding DSN after a 
session is closed? Do they just get dropped? (This is not as simple as 
it sounds, since if a relay is not aware of the session closure, it will 
still try to send the DSN, wasting resources.)

Or, do we want to be able to deliver DSN outside of the scope of the 
session in which it was generated?

I have had several offline discussions with people, and have gotten 
opinions that range from allowing DSN to be sent days later, to assuming 
that all outstanding DSN just get discarded.

Thoughts?

_______________________________________________
Simple mailing list
[email-masked]
https://www1.ietf.org/mailman/listinfo/simple