SIP 180 Ringing vs 436 Bad Identity-Info
SIP 180 (Ringing) is a 1xx Provisional response, while 436 (Bad Identity-Info) is a 4xx Client Failure response. 180 indicates that the UA receiving the INVITE is trying to alert the user. This response is used to initiate local ringback tone at the caller's end. In contrast, 436 means that the Identity-Info header contains a URI that the server cannot dereference to obtain the signing certificate.
Описание
The UA receiving the INVITE is trying to alert the user. This response is used to initiate local ringback tone at the caller's end.
Когда вы это видите
During call setup when the callee's phone is ringing. You should hear a ringback tone after receiving this response.
Как исправить
No fix needed — the callee's device is ringing. If the call never connects after ringing, check the callee's device or call forwarding settings.
Описание
The Identity-Info header contains a URI that the server cannot dereference to obtain the signing certificate.
Когда вы это видите
When the Identity-Info URI in the request points to an unreachable or invalid certificate location.
Как исправить
Ensure the Identity-Info URI is reachable and points to a valid certificate. Check DNS resolution and TLS configuration.
Ключевые различия
180 is a 1xx Provisional response, while 436 is a 4xx Client Failure response.
SIP 180: The UA receiving the INVITE is trying to alert the user. This response is used to initiate local ringback tone at the caller's end.
SIP 436: The Identity-Info header contains a URI that the server cannot dereference to obtain the signing certificate.
You encounter 180 when during call setup when the callee's phone is ringing. You should hear a ringback tone after receiving this response.
You encounter 436 when when the Identity-Info URI in the request points to an unreachable or invalid certificate location.
Когда что использовать
For 180 (Ringing): No fix needed — the callee's device is ringing. If the call never connects after ringing, check the callee's device or call forwarding settings. For 436 (Bad Identity-Info): Ensure the Identity-Info URI is reachable and points to a valid certificate. Check DNS resolution and TLS configuration.