10.3 Cisco Unified Mobility Call Flows

This topic describes call flows when Cisco Unified Mobility is used.

Mobile Connect Call Flow: Incoming Calls to Office Phone

The figure illustrates the call flow when Mobile Connect is used. The figure shows an IP phone with extension 2001 and a mobile phone that belongs to the user of the IP phone.

In this example, a PSTN user calls the office number of the user. Because Mobile Connect is enabled, both the desktop phone 2001 and the configured remote destination (mobile phone 408 555-1001) ring simultaneously. The call is presented to the remote phone, with the original caller ID (479 555-1555). As soon as the call is accepted on one of the phones, the other phone stops ringing. The user can switch the call between the office phone and the mobile phone (and vice versa) during the call, without losing the connection.

Mobile Connect Call Flow: Internal Calls Placed from Remote Phone

This section describes the call flow of a call that is placed from a remote phone to an internal destination.

Mobile Connect influences the calling-number presentation. If a call is received from a recognized remote destination, the corresponding internal directory number, not the E.164 number of the remote device, is used as the calling number.

In the example, extension 2001 has a Mobile Connect remote destination 408 555-1001 (cell phone of the user of 2001). The user places a call from the mobile phone to an enterprise PSTN number of a colleague (by dialing 1 511 555-2002). The called colleague sees the call as coming from the internal directory number 2001 instead of the external mobile phone number.

The same applies to calls that are placed to other internal destinations, such as voicemail. If the user of extension 2001 places a call from the cell phone to Cisco Unity, Cisco Unity sees directory number 2001, not the PSTN number of the cell phone (408 555-1001), as the source of the call. Cisco Unity can identify the user by that directory number and can provide access to the appropriate mailbox instead of playing a generic welcome greeting.

To recognize Mobile Connect remote destinations, the Mobile Connect remote destination number must match the ANI of the incoming call. Mobile Connect remote destinations typically include an access code; for example, 9 in the number 9 1 408 555-1001. The access code 9 and the long distance 1 must be prefixed to the incoming ANI 408 555-1001 to recognize the source as a Mobile Connect remote destination. Alternatively, the Cisco CallManager service Matching Caller ID with Remote Destination parameter can be set to Partial Match, and the Number of Digits for Caller ID Partial Match value can be set. This value specifies how many digits of the incoming ANI (starting with the least significant digit) must match a configured remote-destination number.

If the source of the call is not recognized as a Mobile Connect remote destination, the PSTN number of the remote destination is used for the calling number and is not changed to the internal directory number.

Mobile Voice Access Call Flow

This section describes call flows when the Cisco Unified Mobile Voice Access feature is used.

When Mobile Voice Access is used, users can place calls from a remote destination to the outside, as if they were dialing from the desktop phone. In the example, the user of the IP phone with directory number 2001 uses a cell phone (408 555-1001) to dial the PSTN number of the headquarters, extension 2999. The gateway is configured to start an IVR call application for calls that are placed to that number. The call application, which is based on VXML, offers a prompt and asks for the remote destination number and the PIN of the user. After login, the user can activate and deactivate Mobile Voice Access and can initiate a call from the enterprise network. The call is set up with the E.164 PSTN number of the IP phone that has directory number 2001, instead of with 408 555-1001. This action allows the called party to identify the caller by the (single) office number of the user. The fact that the call is actually placed from a mobile phone instead of the office IP phone does not matter; the call appears to come from the office phone.

After the user has used Mobile Voice Access to initiate a call from a remote destination, the user can switch the call to the office phone and back again as needed, without losing the connection.