Re: Sigtran extension for network management and association changeover.

Xiangsong,

Please see comments below:

Xiangsong Cui wrote:                      (Fri, 05 Mar 2010 14:57:56)
> 
> I don't think so, it seems the M2PA is reusing the functionality
> of MTP2, just using BSN to acknowledge the peer's FSN.

Check M2PA before draft 4.

> 
> They are for different purpose (vs application level ack) and 
> compatible, association changeover is harmless to any application.

Additional complexity and performance impact is not harmless.

> In fact, if the peer doesn't support CORID, the only benefit relies on
> the buffer of local SPP. However, most UA SPPs don't provide buffering
> function, so what can these UA SPPs get in this situation?

Standards compliant UAs must buffer to support AS-PENDING state.

> 
> I can't agree changeover is a local feature. If you only want 
> time-controlled changeover, you may use SCTP Receive Unsent 
> Message primitive defined in RFC4960, ignoring the sent but not 
> acknowledged messages, why buffer the unsent messages in UA 
> layer?

No you cannot because you risk message duplication which is 3
orders of magnitude worse than message loss for SS7.

> 
> As you said in your draft, local implementation is not engough
> for the expected benefit, and we do wish a feasible solution for 
> the high-performance Sigtran network.

No, that's not what I said.  Local implementation is not enough
for the _full_ benefit.  Nevertheless there is still _benefit_
to be had by one or both ends performing the Interworking Procedures.

--brian

-- 
Brian F. G. Bidulock
[email protected]
http://www.openss7.org/