Bob,
thank you very much for your comments. I think you're right pointing out that allowing or disallowing CDOR taking place for certain kinds of redirections (such as CFU) is a question of configuration/policy.
If, on the other hand, the idea of CDOR is to send the call to a "known" location (e.g., to warn everyone in a particular building - a reverse 911), then it would override every redirection feature. Maybe we need some parameter to clarify the particular intent.
That's a good idea, but I'm not too sure whether adding such an "intent" parameter would do the trick here. With CDOR you have the possibility to specify "don't follow any redirection at all". To stay with your example, your switch in this case would inhibit any re-routing due to the "Call Coverage" feature but still invoke any re-routings due to the "Call Forward" feature.
To alter this behaviour (in order to even inhibit the "Call Forward" re-routings), we certainly could add such an "intent" field. I think, however, that combining CDOR with other services, such as H.460.14 (MLPP), H.460.4 (Call Priority) or even H.450.11 (Call Intrusion) might be more useful here. This would keep our CDOR document small and wouldn't duplicate any behaviour.
On the other hand, let's assume a calling endpoint invokes both "Call Priority Designation" (setting a high priority) and CDOR at the same time. What should be the outcome? When a call rerouting is attempted, we'd still have to decide whether it's okay to divert or not. The elevated priority perhaps wouldn't be too helpful in making a decision.
So perhaps adding an intent-parameter ("call the person" or "call the endpoint") might be helpful anyway -- but still, this is already indicated by sending the request for "no re-routings at all".
I'm a bit undecided here and need to do some more reading regarding this issue. If you have any ideas here, they are certainly welcome!
With best regards,
Danilo Kempf (TE-SYSTEMS GmbH)