Re: Re : Query regarding reachability STATUS of Signaling Point Code

Rajesh,

Rajesh Makhija wrote:                        (Sat, 20 Mar 2010 15:35:16)
> Xiangsong,
> 
> Thank you for pointing this out.
> 
> I was originally wondering if SGW does send DAVA for routing context X
> only then how should AS/ASP interpret the same.
> 
> At this moment I am not sure if this (SGW sending DAVA with routing
> context X only) can happen in a real life network.
> 
> And whether it is possible that a route for an SS7 destination is
> available for one AS and not available for second AS through the same
> SGW (given that both AS(s) are in Active state).

Yes, it is possible.

> 
> I would request others to comment on the following two points:
> 
> 1. Whether it is possible that a route for an SS7 destination is
> available for one AS (AS-1) and not available for second AS (AS-2)
> through the same SGW (given that both AS(s) are in Active state), When
> a "common ASP" is serving both AS-1 and AS-2 (given the common ASP is
> active for both AS-1 and AS-2)

Yes, it is possible.

> 2. Whether it is possible that a route for an SS7 destination is
> available for one AS (AS-1) and not available for second AS (AS-2)
> through the same SGW (given that both AS(s) are in Active
> state), When "two mutually exclusive" ASP(s), say ASP-1 and ASP-2 are
> serving AS-1 and AS-2 respectively (given the ASP-1 is active for AS-1
> and ASP-2 is active for and AS-2)

Yes, it is possible.

Just because it is one SG does not mean that all AS that
it serves have the same connectivity or routing to the SS7
network.  For example, AS-1 may use one set of signalling
links, and AS-2 may use another.  Conditions in the SS7
network may cause one route set to become unavailable to
one AS, yet it is available to another.

The ASP, however, does not need to know this.  All it needs
to do is identify which AS correspond to an SNMM message
(from the RC or NA in the message) and deliver the
corresponding MTP primitive.

This is in contrast with SGP within an SG: when an SS7
destination is inaccessible to an AS via one SGP it is
inaccessilble to that AS via all SGP forming an SG.

--brian

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