Enabling call forwarding for Lync response group

Question

When Lync response group receives a call, Lync server does not apply users call forwarding options or simultaneous ringing.

It seems to me that there is a header in SIP message, that prevents call forwarding for response group calls.

Can this behaviour be changed with a MSPL-script or other way?

Answer 1

Forwarding calls to response group can be done with a trusted server application.

Create UserEndpoint for all members of response group and register them for incoming calls.

When incoming call event is received, check if it is from response group and forward it with

e.call.Forward(forwardUri);

Here's how to check if the call is coming from response group: Detect if incoming call is destined to response group

Call forwarding options for a user can be received by registering UserEndpoint to receive presence notifications. In presence notification there is a routing category, which contains forwarding options.

Answer 2

Yes in can be done in a MSPL script/server application.

Michael Greenlee has a article on just this subject here.

Answer 3

To paraphrase M. Greenlee on this subject here, calls from the Response Group to it's member contain two extra SIP Headers: Ms-Sensitivity and Ms-Target-Class. These two headers make that the user's call forwarding settings are ignored, for the following reasons:

Keep in mind that the default behavior of ignoring call forwarding is mostly by design: often you don’t want Response Group calls to go to your cell phone, for a couple of reasons. First, depending on the type of calls that are going through Response Groups, you may not want to be interrupted by these calls on your cell phone. Second, if a Response Group call gets picked up by your cell phone voice mail, for instance, Response Group Services will consider that call answered, and it may not go to another person who is actually available to take it.

If you do want to alter this behavior, add an MSPL script to the pipeline and remove those headers. Sadly, MSPL itself does not have code to remove headers, so you will need to dispatch to a managed application. For a detailed implementation, see the before mentioned post.