Here is a brief discussion about some features that are not yet implemented into VOCAL but have been the subject of enthusiastic conversations among VoIP developers.
Call Park and Call Pickup is like Call Transfer. When a call is received, a user may want to park it on the system and then pick it up at another phone that is on the same network. A user puts a call on hold, and then the same user or a different user picks up the call from a different phone. When the call is picked up, the original phone that is holding the call has to be contacted to transfer the call to the user’s new location. From a technical point of view, this is not a major issue and has been discussed as being a transfer mechanism that would work with the SIP REFER message. From a human point of view, it is a different story.
The basic problem is that, when one user parks a call for someone else, she needs to tell the other user which call to pick up. In many organizations, the user who is picking up the call enters the phone number for the extension where the call was parked. The call that was parked likely came in on the main number, 1000; therefore, the user wants to pick up whatever call is parked on extension 1000.
However, if a call is waiting on 1000, it may be preventing other calls from coming into the switchboard. This problem is circumvented by including parking locations within the system to enable the receptionist, or any other user, to transfer a call to a parking ...