SIP 181 Call Is Being Forwarded vs 513 Message Too Large
SIP 181 (Call Is Being Forwarded) is a 1xx Provisional response, while 513 (Message Too Large) is a 5xx Server Failure response. 181 indicates that a proxy server may send this to indicate that the call is being forwarded to a different set of destinations. In contrast, 513 means that the server was unable to process the request since the entire SIP message (not just the body) exceeded the size limit.
Descripción
A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
Cuándo lo verás
When the callee has call forwarding enabled and the request is being redirected to another number or device.
Cómo solucionarlo
No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings.
Descripción
The server was unable to process the request since the entire SIP message (not just the body) exceeded the size limit.
Cuándo lo verás
When the total SIP message (headers + body) is too large. Different from 413 which refers only to the body.
Cómo solucionarlo
Reduce the message size by removing unnecessary headers or reducing the SDP size. Consider using UDP-compatible message sizes (< 1300 bytes).
Diferencias clave
181 is a 1xx Provisional response, while 513 is a 5xx Server Failure response.
SIP 181: A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
SIP 513: The server was unable to process the request since the entire SIP message (not just the body) exceeded the size limit.
You encounter 181 when when the callee has call forwarding enabled and the request is being redirected to another number or device.
You encounter 513 when when the total SIP message (headers + body) is too large. Different from 413 which refers only to the body.
Cuándo usar cada uno
For 181 (Call Is Being Forwarded): No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings. For 513 (Message Too Large): Reduce the message size by removing unnecessary headers or reducing the SDP size. Consider using UDP-compatible message sizes (< 1300 bytes).