Dialects in MTP and ISUP is not really that bad, and if you as a basis cover ANIS & ETSI you will have a good start. But, you should have a clear plan on how to deal with local variants.
The problematic 'variants' are the off-spec vendor ones. You will see some on ISUP, but more on INAP. The vendors even make special adaptions for countries/regions that are off-spec. A solid implementation of ETSI and ANSI + a good plan for local variations is a MUST! libpri does this the painfull way! Any change to any variant might affect them all leaving us with a maintenance problem. My personal favour is to use the ITU-T as basis and use tables to deal with variants where a message is processed in a handler specific for that variant, leaving the handler for all other variants unchanged. The reason I swear to this is maintenance and the need to know that a conformance test still is valid even if I added a new strange variant. --- The mtp on chan_ss7 must be split into separate mtp2 and mtp3 implementations! mtp3 virtually don't exist in chan_ss7. As for SCCP, TCAP & INAP etc keep in mind that these are ASN.1 so the codec's can be generated from other open souce tools, leaving only the state-engines to be written - could save you some work + it would only need a new ASN.1 to enter a new variant. Jan Jonathan J Smith skrev: > I would answer this question a couple of ways. > > The intent is to establish a solid codebase, then work to enhance said > codebase in the directions that it truly needs to be expanded in. > > I will make this statement about SS7 support. This is something VERY near > and dear to myself personally, as well as several other members of the > development team. I must caution you a bit in that SS7 is HUGE, and saying > 'supports' SS7 is a bit misleading in that there are MANY different subsets > of SS7 and SS7 functionality that are or are not supported by various > efforts out there. For example most do not delve too deep into much or any > support for TCAP type messages etc. > > > Jonathan Smith > > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Anton > Sent: Tuesday, March 14, 2006 12:50 PM > To: [email protected] > Subject: [Openpbx-dev] SS7 > > Hello! > > Just found your resource and I can say that I like your > approach! > > One more thing in my oppinion would me hugely valuable in > the OpenPBX - is the SS7 support. www.sifira.com/chan-ss7 > wrote a working chan_ss7 and it's released under GPL - so I > do think nothing stops it's inclusion to a development > tree. > > Sorry to ask that questions here, as I understood OpenPBX is > a fork of the Asterisk - and the question is: is it > supposed to integrate the patches/fixes/improvements/new > features from asterisk tree? > > Regards, > Anton. > _______________________________________________ > Openpbx-dev mailing list > [email protected] > http://lists.openpbx.org/mailman/listinfo/openpbx-dev > > _______________________________________________ > Openpbx-dev mailing list > [email protected] > http://lists.openpbx.org/mailman/listinfo/openpbx-dev > > > > > _______________________________________________ Openpbx-dev mailing list [email protected] http://lists.openpbx.org/mailman/listinfo/openpbx-dev
