CHAPTER 3. SIP Gateway Management374 © SAMSUNG Electronics Co., Ltd.Configuring Enhanced SIP Gateway FeaturesConfiguring PSTN Cause Code MappingThis section describes the method of mapping between SIP status code andPSTN Cause code. For calls to be established between a SIP network and aPSTN network, the two networks must be able to interoperate. One aspect oftheir interoperation is the mapping of PSTN cause codes, which indicatereasons for PSTN call failure or completion, to SIP status codes or events.The opposite is also true: SIP status codes or events are mapped to PSTNcause codes.A Ubigate iBG2016 provides a SIP- PSTN default mapping table. The method foran operator to change the mapping is also provided. You can change the mappingusing set pstn-cause command and set sip-status command. You can check thecurrent mapping table settings using the show sip-ua maps command.Restrictions for PSTN Cause Code MappingUsing the command described above, you can change the existing inter-codemapping, not create a new code.Default Mappingy Default PSTN Cause Code to SIP Status Code MappingTable 3.4 Table Default PSTN cause code to SIP status code mappingPSTN CauseCode Description SIP Event1 Unallocated number 404 Not found2 No route to specified transit network 404 Not found3 No route 404 Not found17 User busy 486 Busy here18 No user response 480 Temporarilyunavailable19 No answer from the user 480 Temporarilyunavailable20 Subscriber absent 480 Temporarilyunavailable21 Call rejected 403 Forbidden
