Re: M3UA : How to deal whit Unexpected ASPSM/ASTM Message (Jacky Chen)

chen.puran,

[email protected] wrote:               (Thu, 21 Jun 2007 08:54:10)
> 
> Thanks,brain
> 
> but new questions are :
> 1: for  question One,when received unexpected ASP INACTIVE Ack message,ASP
> should Send ASP-DWON Message to
> return itself to its previous state???

Quite simply, when the ASP receives an unsolicited ASP Inactive Ack message
it places the ASP in the ASP-INACTIVE State for the AS indicated in the ASP
Inactive Ack message.  If the ASP was not already in the ASP-INACTIVE State
for the AS indicated in the unsolicited ASP Inactive Ack message, then the
ASP should initiate steps to return the ASP to the previous state for the AS.
If that previous state was ASP-DOWN (for _all_ AS), the way to initiate
returning the ASP to the appropriate state for the AS is to send an ASP Down 
message.

> 
> 2: for question Two: why not discard the unexpected  ASP UP ACK or ASP
> INACTIVE ACK OR ASP ACTIVEACK
>   When ASP IS IN ASP-DOWN Status?

Why do you have ASP Active Ack message in this list?  Nowhere does it say
in the RFC to use these unsolicited procedures for ASP Active Ack.  Also,
they really just pertain to ASP Inactive Ack and ASP Down Ack, where the
SGP is using these messages to force the ASP to the ASP-INACTIVE or ASP-DOWN
states.

> because when ASP ENTER ASP INACTIVE When received  unexpected ASP Up Ack
> message,the AS Contain THE ASP maybe enter into AS-INATIVE Status
> temporarily ,This is not reasonable.

Completely reasonable: the SGP is required to send ASP Up Ack in
response to ASP Up, in which case the ASP Up Ack is always expected
by the ASP, cf. RFC 4666 4.3.4.1.  The only reason for an unexpected
ASP Up Ack is some sort of error, in which case the procedure will
attempt to properly resynchronize state.

> 
> i think in rfc4666,it need to explain how to deal with every unexpected
> ASPSM/TM Message in every as/asp status .

It does: but you need to thoroughly read the RFC to see that.

--brian

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