Re: User Part Unavailable at ASP in M3UA

Kuldeep,

Kuldeep Janjua wrote:                           (Mon, 18 Dec 2006 16:07:35)
> 
>    Mahantesh,
>    ASP Inactive have following parameters:
>    1.Routing Context
>    [1]2.INFO
>    I  think  what  Brian  is discussing is that ASP Inactive Message will
>    contain the routing context parameter, which will let SGP to know that
>    corresponding  traffic  range is not available and then SGP can handle
>    the message accordingly. But its not specified anywhere in the RFC.

Actions taken toward the SS7 network are implementation dependent, however,
UPU sent when an AS with an RK based on SI value is unavailable is obvious.

>    >From  my  point  of view Error Message with "Invalid Routing Context"
>    should  be sent, which will stop the further processing of the message
>    at SGP.

Bad thing to do: the RC is valid.

>    As  per  definition SCON is signalling congestion message so it can be
>    sent  from ASP only in the case when M3UA at ASP detects that there is
>    congestion  for  the  corresponding  user  part.So it take care of "UP
>    unavailability" in case of  "congestion at ASP for UP" only.

SCON from ASP to SGP is used to signal M3UA congestion (not user part
congestion).  As in SS7, MTP user part congestion is handled within the
user part protocol (e.g. congestion parameter in ISUP release messages).

>    There can be other reasons as well for user part unavailability. Those
>    cases are also required to taken care of.

If an PC based RK is used (all SI values, thus all MTP-Users) then the SG
assumes that all user parts for the PC live or die together (i.e. are all
available or all unavailable).  This is the same for SS7 based on a PC-wide
MTP-SAP (which was only specified in older ANSI documents).

--brian

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