SIP 202 Accepted vs 404 Not Found
SIP 202 (Accepted) is a 2xx Success response, while 404 (Not Found) is a 4xx Client Failure response. 202 indicates that the request has been accepted for processing but the processing has not been completed. Used primarily for REFER requests. In contrast, 404 means that the user specified in the Request-URI does not exist at the domain. The server has authoritative information that the user does not exist.
Descripción
The request has been accepted for processing but the processing has not been completed. Used primarily for REFER requests.
Cuándo lo verás
After sending a REFER request for call transfer. The transfer target acknowledges receipt but hasn't completed the transfer yet.
Cómo solucionarlo
Wait for a NOTIFY to learn the outcome of the referred action. If no NOTIFY arrives, check subscription state and network connectivity.
Descripción
The user specified in the Request-URI does not exist at the domain. The server has authoritative information that the user does not exist.
Cuándo lo verás
When calling a number or SIP address that does not exist on the server. Different from 480 (user exists but is temporarily unavailable).
Cómo solucionarlo
Verify the SIP URI or phone number. Check if the user is registered on the correct domain. Ensure the domain is correct.
Diferencias clave
202 is a 2xx Success response, while 404 is a 4xx Client Failure response.
SIP 202: The request has been accepted for processing but the processing has not been completed. Used primarily for REFER requests.
SIP 404: The user specified in the Request-URI does not exist at the domain. The server has authoritative information that the user does not exist.
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 404 when when calling a number or SIP address that does not exist on the server. Different from 480 (user exists but is temporarily unavailable).
Cuándo usar cada uno
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 404 (Not Found): Verify the SIP URI or phone number. Check if the user is registered on the correct domain. Ensure the domain is correct.