SIP 202 Accepted vs 204 No Notification
Both SIP 202 (Accepted) and 204 (No Notification) belong to the 2xx Success category. 202 indicates that the request has been accepted for processing but the processing has not been completed. Used primarily for REFER requests. Meanwhile, 204 means that the request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request.
Descrição
The request has been accepted for processing but the processing has not been completed. Used primarily for REFER requests.
Quando você o vê
After sending a REFER request for call transfer. The transfer target acknowledges receipt but hasn't completed the transfer yet.
Como corrigir
Wait for a NOTIFY to learn the outcome of the referred action. If no NOTIFY arrives, check subscription state and network connectivity.
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.
Diferenças principais
SIP 202: The request has been accepted for processing but the processing has not been completed. Used primarily for REFER requests.
SIP 204: The request was successful but the server has decided not to send a NOTIFY for this SUBSCRIBE request.
You encounter 202 when after sending a REFER request for call transfer. The transfer target acknowledges receipt but hasn't completed the transfer yet.
You encounter 204 when when subscribing to event packages that may not generate immediate notifications, such as dialog or presence packages.
Quando usar qual
For 202 (Accepted): Wait for a NOTIFY to learn the outcome of the referred action. If no NOTIFY arrives, check subscription state and network connectivity. For 204 (No Notification): No fix needed. The subscription was accepted but there is no state change to notify about yet.