SIP 180 Ringing vs 412 Conditional Request Failed
SIP 180 (Ringing) is a 1xx Provisional response, while 412 (Conditional Request Failed) 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, 412 means that the precondition given in the request was not met. Used with SIP event state publication (RFC 3903).
Descrição
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.
Quando você o vê
During call setup when the callee's phone is ringing. You should hear a ringback tone after receiving this response.
Como corrigir
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.
Descrição
The precondition given in the request was not met. Used with SIP event state publication (RFC 3903).
Quando você o vê
When a PUBLISH request includes an If-Match header with an entity tag that does not match the current state on the server.
Como corrigir
Refresh the entity tag by performing a new PUBLISH without If-Match, then use the returned SIP-ETag for subsequent updates.
Diferenças principais
180 is a 1xx Provisional response, while 412 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 412: The precondition given in the request was not met. Used with SIP event state publication (RFC 3903).
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 412 when when a PUBLISH request includes an If-Match header with an entity tag that does not match the current state on the server.
Quando usar qual
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 412 (Conditional Request Failed): Refresh the entity tag by performing a new PUBLISH without If-Match, then use the returned SIP-ETag for subsequent updates.