SIP 202 Accepted vs 416 Unsupported URI Scheme
SIP 202 (Accepted) is a 2xx Success response, while 416 (Unsupported URI Scheme) 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, 416 means that the server cannot process the request because the URI scheme in the Request-URI is unknown to the server.
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 server cannot process the request because the URI scheme in the Request-URI is unknown to the server.
Quando você o vê
When using a URI scheme (e.g., tel:, im:, pres:) that the receiving server does not support.
Como corrigir
Use a supported URI scheme. Most SIP servers support sip: and sips: schemes. Check server capabilities with OPTIONS.
Diferenças principais
202 is a 2xx Success response, while 416 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 416: The server cannot process the request because the URI scheme in the Request-URI is unknown to the server.
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 416 when when using a URI scheme (e.g., tel:, im:, pres:) that the receiving server does not support.
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 416 (Unsupported URI Scheme): Use a supported URI scheme. Most SIP servers support sip: and sips: schemes. Check server capabilities with OPTIONS.