SIP 180 Ringing vs 428 Use Identity Header
SIP 180 (Ringing) is a 1xx Provisional response, while 428 (Use Identity Header) 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, 428 means that the server requires an Identity header to verify the caller's identity but it was not included in the request.
Description
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.
Quand vous le voyez
During call setup when the callee's phone is ringing. You should hear a ringback tone after receiving this response.
Comment résoudre
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.
Description
The server requires an Identity header to verify the caller's identity but it was not included in the request.
Quand vous le voyez
In environments that enforce SIP Identity (RFC 4474) for caller authentication and spam prevention (STIR/SHAKEN).
Comment résoudre
Add a valid Identity header signed by an authentication service. Ensure your STIR/SHAKEN infrastructure is properly configured.
Différences clés
180 is a 1xx Provisional response, while 428 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 428: The server requires an Identity header to verify the caller's identity but it was not included in the request.
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 428 when in environments that enforce SIP Identity (RFC 4474) for caller authentication and spam prevention (STIR/SHAKEN).
Quand utiliser lequel
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 428 (Use Identity Header): Add a valid Identity header signed by an authentication service. Ensure your STIR/SHAKEN infrastructure is properly configured.