Origin based routing and Sourse Addresses in Routing Key Definition

Hello Folks,

recently in "ASP Capabilities value 0x2 of interworking field" thread

On 12/20/05, Brian F. G. Bidulock <[email protected]> wrote:
> Stanislav,
>
> Stanislav Ivanovich wrote:                                       (Tue, 20 Dec 2005 07:44:05)
> >
> >
> > ....
> >    In  xxUA networks AS/RC concept in mandatory SE model both originating
> >    and   destination   addresses   have   to   be   specified   and  only
> >    these combinations  are  allowed.  This  is  extremely  unfriendly for
> >    relay!
>
> No they don't.  Any routing key is possible.  Dynamic registration does not
> support all possible routing keys.  Provisioned routing keys can take any
> form.  Also note that SUA registration supports multiple and ranges of
> addresses in a dynamically registered routing key.  Not even M3UA restricts
> its routing keys to a single originating or destination point code.  You
> can have one destination HLR point code and 400 MSC originating point codes
> if you'd like.  Or visa versa.  Or 400 of each.
>
> >

IMO having Originating Addresses in the definition of the AS and RK
was a very nice idea. Most probably the reason for it was to off-load
the destination Signalling Processes and have finer granularity in
traffic routing and distribution via origin based routing (due to low
capacity Signalling Processes).

In case of SE-IPSP when dynamic RKM is in use, ASs and RKs shall
contain both source and destination addresses as part of RK
definition. As long as Relay is not used having source and destination
addresses as part of RK does not imply routing based on origin, where
depending on source address traffic can go to different IP
destinations although the SS7 destination address is the same.

As consequence of SE-IPSP and dynamic RKM, the definition of the AS
has drifted to the a concept of signalling relation with one or more
applications on one side of it and one or more applications on the
other side. As far as I understand there was no objective to enforce
origin based routing as a mandatory feature for relay. However, having
SE mandatory, one can draw the conclusion that origin based routing is
mandatory for Relay nodes.

Brian's statement above "Provisioned routing keys can take any form"
is fine with me, and hopefully with everybody on this list, since it
was not objected by anyone.
I interpret it as "origin based routing is optional in Relay nodes".

Please can people on the list make clear whether it is mandatory or
optional  for SUA relay to have routing based on source address.

I was not able to fine any statement in the RFC that makes routing
based on origin mandatory, except the fact that SE is mandatory.

Thank you in advance

Ilie