Commit
29f355720d9509ebfcec9422a607031d02cb904e
by Pau Espin Pedrol
ttcn3-asterisk: Add extra IP addr in ttcn3 docker for IMS Core
TTCN-3 docker container is emulating both the SIP UAs and the IMS Core. So far all the components being emulated there were running under the only local IP address available in the docker container. This means, both the SIP UAs and the IMS Core were using the same IP address.
This is actually causing problems for Asterisk, since on the VoLTE side it needs to be configured to identify the endpoint based on the IMS Core domain name. Since the default identify matching ordered in Asterisk is: "endpoint_identifier_order=ip,username,anonymous" That means it always first checks the source IP address, which means messages coming from local SIP UAs are misunderstood to be coming from the IMS Core (since ims.mnc001.mcc238.3gppnetwork.org resolves to same IP address).
The issue can be fixed by swapping the order to "username,ip", because then the well-known 50X extensions are matched before attempting to match by IP address. However, this is all deviating config for the expected usual network configuration, since the local IP network will be different than the IP address coming from VoLTE. Hence, let's instead properly separate the local SIP and VoLTE networks with different IP addresses, which then solves the issue.