Configuring and Using Directed Call Park
Directed Call Park provides a mechanism for telephony users to predictably place a call in a targeted park slot. When combined with park reversion to a specified DN, and busy-lamp for direct call park, there are some neat tricks and customizations that can be performed around call park.
Using directed call park is a little different to "traditional" call park which is initiated using a soft-key; with directed call park:
- To park a call: Perform a blind transfer to the call park DN
- To retrieve a call: Dial a prefix + the call park DN
From a configuration perspective, directed call park requires:
- Defining a DN or DN range for Directed Call Park. Note that although wild cards can be used (such as "80XX"), if you need to add a Directed Call Park phone button to a phone or UDP, the DN will not appear in the list - only explicitly defined DN's can be assigned to phone buttons. In other words, if 80XX and 8100 are both configured as Directed Call Park numbers, only 8100 can be assigned to a button
- A retrieval prefix must be set under the DN. It is important that the retrieval + Call Park DN does not conflict with the existing dial plan
- Optionally, set a Reversion Number under the Call Park DN. If this is set, when the Call Park Reversion timer expires (set under Service Parameters > CallManager Service), the call is reverted to an alternate extension, such as Reception or a service queue
- Once the Directed Call Park has been configured, if an explicit DN was used (i.e. no wildcards) a Busy Lamp Field Directed Call Park button can be assigned and configured on a UDP, or to a hard IP phone. I could see this being of use in certain team environments where call park is an important part of the work flow, and the simple capabilities of call park are inadequate.
If a call park slot is already in use and an additional calling party attempts to transfer a call to the same slot, an error displays on the IP phone display that the call slot is in use. The error is shown below. The same error will be shown to a user if they forget, for example, to enter the prefix before dialling the call park slot.

Defining a Directed Call Park Number (or range)

Customizing the Call Park Reversion Timer

Assigning the Directed Call Park as a BLF

Attempting to dial an in-use call park slot