SIP 181 Call Is Being Forwarded vs 604 Does Not Exist Anywhere
SIP 181 (Call Is Being Forwarded) is a 1xx Provisional response, while 604 (Does Not Exist Anywhere) is a 6xx Global 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, 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.
الوصف
A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
متى تراه
When the callee has call forwarding enabled and the request is being redirected to another number or device.
كيفية الإصلاح
No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings.
الوصف
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.
متى تراه
When the user definitively does not exist on any server in the network. The server has authoritative knowledge, not just local.
كيفية الإصلاح
The user does not exist. Verify the SIP URI or phone number. Unlike 404, retrying on other servers will not help.
الفروق الرئيسية
181 is a 1xx Provisional response, while 604 is a 6xx Global 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 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 181 when when the callee has call forwarding enabled and the request is being redirected to another number or device.
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.
متى تستخدم أيًا منهما
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 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.