Making a call when a user is experiencing wireless network congestion
Even if you have configured your organization's users for PBX-initiated calling, if users makes calls when they are experiencing wireless network congestion, the BlackBerry MVS Client uses BlackBerry device-initiated calling to make the call.
- A BlackBerry Mobile Voice System user within an organization, who is in an area with wireless network congestion, uses a BlackBerry device to dial the extension number of another BlackBerry MVS user. The BlackBerry MVS Client starts a timer.
- The BlackBerry MVS Client creates a call establishment request, which includes the destination number. The BlackBerry MVS Client compresses and encrypts the call establishment request, and tries to send the request to the BlackBerry Enterprise Server over the wireless network.
- Due to network congestion the call establishment request does not reach the BlackBerry Enterprise Server before the timer on the BlackBerry device expires.
- The timer on the BlackBerry MVS Client expires, and the BlackBerry MVS Client sends a BYE message to the BlackBerry MVS Server to end the call.
- The BlackBerry MVS Client uses the no data coverage calling number (that the administrator configured for the BlackBerry MVS Server) to call the MVS Session Manager.
- The MVS Session Manager answers the call.
- The BlackBerry MVS Client sends an authorization code and the number it wants to call to the MVS Session Manager using DTMF tones.
- The MVS Session Manager, using a SIP line, requests that the PBX establish a call to the internal number using the extension number.
The PBX determines that the extension number is internal to the organization and rings the extension number over the organization's LAN.
- The MVS Session Manager sends a message to the BlackBerry MVS Client to show the desk phone is ringing using DTMF tones.
- The recipient answers the call at a desk phone.
- The MVS Session Manager connects the SIP line call leg to the SIP trunk call leg, and voice communication occurs.
- The MVS Session Manager sends a connected tone to the BlackBerry MVS Client. The BlackBerry MVS Client displays that the call is connected.
- The BlackBerry MVS Client acknowledges to the MVS Session Manager that it received the connected tone.