Hi again, I'm using Kamailio 5.3.2 by the way.
Björn Bylander writes: > Hi, > > So I’m tasked with setting up a SIP trunk to a Perimeta SBC > (https://www.metaswitch.com/products/perimeta-sbc). > > Apparently, > > Perimeta hides the topology of networks by rewriting or removing > > topology-sensitive information from SIP messages. By default, your Session > > Controller will make the following changes to SIP messages. > > > > The Session Controller generates new dialog identifiers (call-IDs, From > > tags and To tags) for each side of the call, so that it does not expose > > information about your core network to your access networks. > > The Session Controller strips Record-Route and Route information from the > > message. > > The Session Controller rewrites Contact and Via headers so that the source > > IP address is replaced with the local address of the outbound adjacency. > > The Session Controller replaces the IP addresses in c= lines in SDP with > > the addresses it has allocated for media forwarding. For more information > > on this, see Media addresses and gates. > > My problem is this: When the Perimeta SBC sends its first INVITE (I can't say > anything about any succeeding INVITEs yet) it's added a Record-Route header > with the "lr" parameter included which, as far as I can see makes Kamailio > think it should use loose routing which is all well I think. But when the SBC > sends an ACK for the "200 OK" from the Kamailio side it doesn't include any > Route headers and I think that makes it hard for Kamailio (at least with the > standard script which is basically what I'm using) to know where to relay the > ACK, at least it makes the t_check_trans() call in WITHINDLG after > 'is_method("ACK")' return false which makes the script ignore the ACK. > > Any thoughts or suggestions on how to handle this? > > Thanks in advance, > Björn Bylander _______________________________________________ Kamailio (SER) - Users Mailing List sr-users@lists.kamailio.org https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users
