Call parking allows users to put a conversation on hold and then resume it from a different IP phone. Users can park a call by dialing the parking prefix, which is *70 by default. To retrieve this call, they can dial the release prefix (by default, *71) followed by either:
Parking and retrieving a call using an extension
Users can park both external calls and calls within PBX by using a parking prefix and any PBX extension.
Consider the following example:
A sales manager, John Doe (extension 333), receives a call from a client. They talk for a while, but it’s too noisy in John’s workspace. John decides to continue the conversation in a conference room. John asks the client to wait a minute until he moves to the conference room. To park the call, John puts it on hold. Then he dials *70333 (where 70 is the call parking prefix followed by John’s extension, 333). John hears the call parking confirmation message and hangs up. This message contains the combined number to retrieve the parked call – *71333 (where 71 is the release prefix and 333 is John’s extension). The client is on hold.
When John comes to the conference room, he dials *71333 to retrieve the call and continue the conversation.
Note that if John wants to unpark the call on his phone, he can dial just the release prefix *71 since his extension was used for call parking.
In the example above, John could also use any extension from the same PBX, even if that extension is not participating in the call, e.g., 999. No matter which extension John uses to park the call, he just needs to use the same extension to retrieve the call. Thus, if John parks the call by dialing 644999, he can retrieve the call by dialing 645999.
The call flow in this scenario is the following:
- Client dials John’s phone number.
- PortaSIP sends an authorization request to PortaBilling to check if John is allowed to accept an incoming call. The call is authorized successfully and PortaBilling sends the list of routes to PortaSIP for further call processing.
- PortaSIP sends the call to John’s phone and John answers.
- The call is established between a client and John.
- John requests to park the call: puts the client on hold and then dials a special call parking prefix (e.g., *70333).
- The client hears music while on hold.
- PortaSIP sends the authorization request to PortaBilling, which verifies that John is allowed to park the call.
- PortaSIP then plays the call parking confirmation message to John. This message contains a number for retrieving the parked call (e.g., *71333, where 71 is a release prefix and 333 is his extension). John hangs up.
- The client is still on hold.
- John requests to retrieve the call from any IP phone in the conference room: he dials the release prefix *71 and his extension 333.
- PortaSIP sends an authorization request to PortaBilling, which determines that this is an attempt to retrieve the parked call and instructs PortaSIP to combine the initial client’s call with the new call initiated by John.
- John is connected to the client from another IP phone.
Parking and retrieving a call using a randomly generated number
Users can also park the call by dialing the parked prefix only (by default, *70). Then they hear the message with a number for retrieving the parked call that is the release prefix and a randomly generated number (e.g., *71*7250, where 71 is a release prefix and 7250 is a randomly generated number). The randomly generated number always has the star as a prefix to distinguish it from the extension. Then to retrieve the call the user dials the announced number from another phone.