One customer in V country have eSpace U1980 (V100R001C01SPC900) device and interconnected with PSTN by R2 trunk, after finish the configuration, they cannot make an outgoing calls, the call was never established.
1. Capture logs and check the signaling, from the signaling we can see U1980 sent out the first called number but didn’t get any response from PSTN.
2. Check with PSTN, and found they are use DTMF type signaling, but default U1980 was using MFC type.
3. Modified U1980 signaling type to DTMF, the command was: config modify board slot x type dtu trunkport x officeno x sendnumbertype dtmf
4. Test again, and the issue was resolved.
1. The configuration in U1980 was not correct, the request didn’t send out.
2. The PSTN received the request message but not response.
Before interconnection with R2 trunk, need to understand the R2 parameter in peer side, such as the type of register singling, the type of line singling , if use B group singling etc.