SIP 204 No Notification vs 487 Request Terminated
SIP 204 (No Notification) is a 2xx Success response, while 487 (Request Terminated) is a 4xx Client Failure response. 204 indicates that the request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request. In contrast, 487 means that the request was terminated by a BYE or CANCEL. The original request was cancelled before it could be completed.
Descrição
The request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request.
Quando você o vê
When subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
Como corrigir
No fix needed. The subscription was accepted but there is no state change to notify about yet.
Descrição
The request was terminated by a BYE or CANCEL. The original request was cancelled before it could be completed.
Quando você o vê
When the caller hangs up before the callee answers (CANCEL sent for pending INVITE). This is normal call abandonment.
Como corrigir
No fix needed — the caller intentionally terminated the request. This is normal behavior.
Diferenças principais
204 is a 2xx Success response, while 487 is a 4xx Client Failure response.
SIP 204: The request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request.
SIP 487: The request was terminated by a BYE or CANCEL. The original request was cancelled before it could be completed.
You encounter 204 when when subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
You encounter 487 when when the caller hangs up before the callee answers (CANCEL sent for pending INVITE). This is normal call abandonment.
Quando usar qual
For 204 (No Notification): No fix needed. The subscription was accepted but there is no state change to notify about yet. For 487 (Request Terminated): No fix needed — the caller intentionally terminated the request. This is normal behavior.