SIP 180 Ringing vs 300 Multiple Choices
SIP 180 (Ringing) is a 1xx Provisional response, while 300 (Multiple Choices) is a 3xx Redirection 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, 300 means that the address in the request resolved to several choices, each with its own location. The user or UA can select a preferred communication endpoint.
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 address in the request resolved to several choices, each with its own location. The user or UA can select a preferred communication endpoint.
Quando você o vê
When a user has multiple registered devices or contact addresses and the server cannot determine which one to use.
Como corrigir
Select one of the provided Contact addresses and resend the request to that specific URI.
Diferenças principais
180 is a 1xx Provisional response, while 300 is a 3xx Redirection 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 300: The address in the request resolved to several choices, each with its own location. The user or UA can select a preferred communication endpoint.
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 300 when when a user has multiple registered devices or contact addresses and the server cannot determine which one to use.
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 300 (Multiple Choices): Select one of the provided Contact addresses and resend the request to that specific URI.