Making Suspend and Resume Connections During Voice Calls

Windows Mobile 6.5

If a voice call occurs after the user activates a packet data connection that is suspend and resume capable, such as GPRS or 1xRTT, and the system does not support Simultaneous Voice and Data Connections, the device suspends the data session for the duration of the voice call instead of disconnecting it. During this state, the device caches the data session and maintains the same IP address. However, actual data cannot be sent or received on it. When the voice call ends, the session is immediately resumed and ready to send and receive data.

An application informs Connection Manager that it is suspend and resume aware by setting CONNMGR_FLAG_SUSPEND_AWARE bit flag in dwFlag member of the CONNMGR_CONNECTIONINFO structure for the connection request. With CONNMGR_FLAG_SUSPEND_AWARE flag set, the application will be notified when the connection request status changes to CONNMGR_STATUS_SUSPENDED. This status is sent when a suspend and resume connection used by the connection request, is suspended. Otherwise, and to maintain backward-compatibility, the application will receive the notification CONNMGR_STATUS_DISCONNECTED to inform it that it cannot send or receive data. Once the voice call is disconnected, the packet data connection will be resumed and the application will be notified with CONNMGR_STATUS_CONNECTED.

Suspend and resume functionality is only available with suspend and resume capable connections. GPRS connections are configured as suspend and resume capable by default. If a Windows Mobile device supports GPRS connections that are not suspend and resume capable or if the Windows Mobile device supports other suspend and resume connections, such as CDMA packet data connection, the connection information must be configured by the OEM or Mobile Operator.

When the network indicates Simultaneous Voice and Data support, the impact on a connection depends on the suspend and resume capability of the connection.

  • A connection that was suspend and resume capable becomes Simultaneous Voice and Data support capable.
  • All other, non-Suspend and Resume, connections remain the same.

Changing a cellular data connection to Simultaneous Voice and Data support capable has the following effects.

  • During the transition from non-Simultaneous Voice and Data support to Simultaneous Voice and Data support, if a connection was in the CONNMGR_STATUS_SUSPENDED state during a voice call, the connection will transition to CONNMGR_STATUS_CONNECTED.
  • During the transition from non- Simultaneous Voice and Data support to Simultaneous Voice and Data support, if the suspend and resume capable connection is in the CONNMGR_STATUS_CONNECTED state, the connection will remain in this state.

If a user roams to a network that does not support Simultaneous Voice and Data, the Simultaneous Voice and Data support connections gets changed to Suspend and Resume connections.

Note   Suspend and resume data call states should not be confused with the CDMA concept of active and dormant states for data calls.



Simultaneous Voice and Data Connections

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