SIP 181 Call Is Being Forwarded vs 603 Decline
SIP 181 (Call Is Being Forwarded) is a 1xx Provisional response, while 603 (Decline) 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, 603 means that the callee's machine was contacted successfully but the user explicitly does not wish to or cannot participate. Unlike 600, this may be because the callee doesn't want to communicate, not necessarily
説明
A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
このコードが表示される場合
When the callee has call forwarding enabled and the request is being redirected to another number or device.
解決方法
No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings.
説明
The callee's machine was contacted successfully but the user explicitly does not wish to or cannot participate. Unlike 600, this may be because the callee doesn't want to communicate, not necessarily because they're busy.
このコードが表示される場合
When the callee explicitly declines the call. This is an active rejection, not a busy or unavailable state.
解決方法
The callee has declined. Respect their decision. Consider alternative communication methods (email, messaging).
主な違い
181 is a 1xx Provisional response, while 603 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 603: The callee's machine was contacted successfully but the user explicitly does not wish to or cannot participate. Unlike 600, this may be because the callee doesn't want to communicate, not necessarily
You encounter 181 when when the callee has call forwarding enabled and the request is being redirected to another number or device.
You encounter 603 when when the callee explicitly declines the call. This is an active rejection, not a busy or unavailable state.
どちらをいつ使うか
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 603 (Decline): The callee has declined. Respect their decision. Consider alternative communication methods (email, messaging).