For Cisco Unified Communication Manager version 12.0:
Dial via office (DVO) functionality provides automated enterprise dialing capabilities that enable dual-mode mobile devices to initiate calls through the enterprise telephony infrastructure.
Deploying DVO calling provides the following benefits to the enterprise:
- Cost savings for calls to international and (possibly) long distance destinations as compared to direct-dialed cellular calls. Note that, in cases of mobile data traversal, mobile data costs must also be considered.
- Ability to dial internal enterprise numbers. Because DVO calls are made using the enterprise line, non-DID or internal-only enterprise extensions are reachable.
- Mobile phone number masking. For DVO calls, the system sends the user's enterprise number as caller ID, and not the mobile phone number.
- Centralized enterprise call detail records (CDRs) and call logs. Because DVO calls are made through the enterprise telephony infrastructure, administrators have complete visibility to these calls even though they traverse the PSTN and mobile voice network.
- Enterprise call anchoring. DVO calls are anchored in the enterprise, thus enabling users to leverage Cisco Unified Mobility DTMF-based mid-call features and desk phone pickup.
Dual-mode mobile devices running the Cisco Jabber client are able to make DVO calls using the Unified CM telephony infrastructure and enterprise PSTN gateway to make calls using the enterprise line. However, unlike voice over IP (VoIP) calling where voice media traverses the IP network, this functionality is facilitated by SIP signaling between the client and Unified CM over an IP connection (WLAN or mobile data) and voice media between the mobile device and the mobile voice network and PSTN.
For DVO calls, all voice or media from the user's mobile phone will always travel through the mobile voice network, PSTN, and enterprise PSTN gateway. Media never traverses the IP data connection to the enterprise. The mobile data network connection is used only for call signaling traffic and other application interactions.
For details on dial via office as implemented for Cisco Jabber clients, refer to: