SIP 181 Call Is Being Forwarded vs 486 Busy Here
SIP 181 (Call Is Being Forwarded) is a 1xx Provisional response, while 486 (Busy Here) is a 4xx Client 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, 486 means that the callee's end system was contacted successfully but the callee is currently not willing or able to take additional calls at this end system.
Descrição
A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
Quando você o vê
When the callee has call forwarding enabled and the request is being redirected to another number or device.
Como corrigir
No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings.
Descrição
The callee's end system was contacted successfully but the callee is currently not willing or able to take additional calls at this end system.
Quando você o vê
When the callee is already on a call and does not have call waiting. The user explicitly rejected the call, or all lines are in use.
Como corrigir
Wait and try again later. The callee may become available when their current call ends. Consider leaving a voicemail if available.
Diferenças principais
181 is a 1xx Provisional response, while 486 is a 4xx Client 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 486: The callee's end system was contacted successfully but the callee is currently not willing or able to take additional calls at this end system.
You encounter 181 when when the callee has call forwarding enabled and the request is being redirected to another number or device.
You encounter 486 when when the callee is already on a call and does not have call waiting. The user explicitly rejected the call, or all lines are in use.
Quando usar qual
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 486 (Busy Here): Wait and try again later. The callee may become available when their current call ends. Consider leaving a voicemail if available.