Client Mobility Support

The components for Client Mobility Support have the role of interacting with the Core Network Mobility Management Components and providing an enhanced experience for the applications running on the client devices. While not mandatory for simple scenarios, the OpenEPC Client Mobility Manager enables automated network selection and handover capabilities, help to implement operator-based networks balancing between different technologies and provide a one-stop interface for exchanging connectivity information and commands with the client based applications.

The OpenEPC Client Mobility Manager is support currently on Linux and Android platforms. Additional platforms can be supported on demand.

In the absence of the Client Mobility Manager, simpler and standard Network Manager can be instead employed. Attachments are standard and common, only their orchestrations as well the use of operator indicated policies, would lack in performance:

• for 3GPP access, standard modem-based connectivity;
• for non-3GPP standard WPA-EAP authentication, followed by DHCP/DHCPv6 procedures.

For providing value-added functionality, the Access Network Discovery and Selection Function (ANDSF) situated in the core network assists the Mobility Manager with information and operator pushed policies.

The ANDSF communicates over the S14 interface based on standard SyncML or alternatively on a simplified XML exchange over TCP with the Client Mobility Manager in the UEs. The information exchanged includes network Discovery Information as well as Inter-System Mobility Policies. Through this component, the operator can optimize both its network re-selection mechanisms, as well as enable advanced features:

• steer devices towards less loaded access technologies or access points
• request users to vacate a base station such that it could turned-off to save power in access overlapping situations
• auto discover access technology coverage
• provide time/location/application based policies on selection and use of access networks
• provide discovery information for non-3GPP wireless technologies

Similar to the PCRF, also the ANDSF is connected to the HSS/SPR and hence Inter-system Mobility policies can be customized on a subscriber-by-subscriber basis.