SIP 202 Accepted vs 604 Does Not Exist Anywhere
SIP 202 (Accepted) is a 2xx Success response, while 604 (Does Not Exist Anywhere) is a 6xx Global 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, 604 means that the server has authoritative information that the user indicated in the Request-URI does not exist anywhere. Unlike 404, this is a definitive, global statement.
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 server has authoritative information that the user indicated in the Request-URI does not exist anywhere. Unlike 404, this is a definitive, global statement.
Cuándo lo verás
When the user definitively does not exist on any server in the network. The server has authoritative knowledge, not just local.
Cómo solucionarlo
The user does not exist. Verify the SIP URI or phone number. Unlike 404, retrying on other servers will not help.
Diferencias clave
202 is a 2xx Success response, while 604 is a 6xx Global Failure response.
SIP 202: The request has been accepted for processing but the processing has not been completed. Used primarily for REFER requests.
SIP 604: The server has authoritative information that the user indicated in the Request-URI does not exist anywhere. Unlike 404, this is a definitive, global statement.
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 604 when when the user definitively does not exist on any server in the network. The server has authoritative knowledge, not just local.
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 604 (Does Not Exist Anywhere): The user does not exist. Verify the SIP URI or phone number. Unlike 404, retrying on other servers will not help.