SIP 181 Call Is Being Forwarded vs 608 Rejected
SIP 181 (Call Is Being Forwarded) is a 1xx Provisional response, while 608 (Rejected) 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, 608 means that an intermediary machine or process rejected the call attempt. Similar to 607 but the rejection comes from the network rather than the end user.
Description
A proxy server may send this to indicate that the call is being forwarded to a different set of destinations.
When You See It
When the callee has call forwarding enabled and the request is being redirected to another number or device.
How to Fix
No action needed. The call is being redirected. If forwarding is unintended, the callee should update their forwarding settings.
Description
An intermediary machine or process rejected the call attempt. Similar to 607 but the rejection comes from the network rather than the end user.
When You See It
When a network element (not the callee) blocks the call. Used by analytics engines and call-blocking services in the network path.
How to Fix
This is a network-level block. Contact the network administrator or carrier to understand why the call was blocked.
Key Differences
181 is a 1xx Provisional response, while 608 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 608: An intermediary machine or process rejected the call attempt. Similar to 607 but the rejection comes from the network rather than the end user.
You encounter 181 when when the callee has call forwarding enabled and the request is being redirected to another number or device.
You encounter 608 when when a network element (not the callee) blocks the call. Used by analytics engines and call-blocking services in the network path.
When to Use Which
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 608 (Rejected): This is a network-level block. Contact the network administrator or carrier to understand why the call was blocked.