Re: RFC 4666 M3UA - Reg Request Message

Lincoln,

The LOADSEL draft provides just such a failover mechanism.

The SS7 network does not route on CIC, it performs load sharing of
messages over SS7 links based on SLS (which is part of the CIC).

ETSI TS 102 142 properly asserts that RKs should be no less than
a Point Code (with the exception that in ANSI networks where Alias
point codes are used per ANSI T1.113/2000 for the GTT function,
distribution on SI value is suitable).

In fact, all such CIC schemes are load sharing and not routing.
What is lacking in the M3UA RFCs (both of them) is the ASPs inability
to control the load selection algorithm to effect efficient call
state sharing and management.  The LOADSEL draft provides just such
a mechanism for CIC and the LOADGRP draft provide another level of
sophistication on the same load selector.

In your failover scenario, under LOADGRP it is even possible for
the ASPs to specify to which alternate ASP a given load selection
fails over to.  For both LOADSEL and LOADGRP, the SG does not need
to understand ISUP to perform its function, yet the ASPs have
complete control over management of call state by specifying to
which ASPs the SG sends which messages.

--brian

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