, the PGW entity can also initiate a session with the PCRF entity to retrieve the profile of the mobile stored in the SPR entity. The PGW entity terminates phase (D) by issuing the Binding Acknowledgment message of the Mobility extension of the IPv6 header. At the end of phase (D), the IP tunnel S2c is established between the mobile and the PGW entity. 9.3.3. IFOM function The IFOM (IP Flow Mobility) function allows the mobile to connect to both LTE (Long-Term Evolution) access and Wi-Fi access simultaneously and to establish multiple sessions from a single connection to the PGW entity. The IFOM feature also allows mobility of the IP stream, with IP streams belonging to the same application or different applications moving seamlessly between LTE access and Wi-Fi access. S2c Tunnel Establishment The IFOM function is used to indicate how the IP streams are routed through the different radio access networks and to selectively unload certain traffic (e.g. Internet traffic) to Wi-Fi access while using the LTE access for other traffics (e.g. voice). The IFOM function requires an evolution of the DSMIPv6 mechanism: - the mobile can register several CoA associated with the HoA; - to register the different CoA/HoA correspondences, the mobile generates a BID (Binding Identifier) for each CoA. The mobile requests the registration of its CoA by sending the Binding Update message; - when the home agent receives the Binding Update message, it copies the BID in its correspondence table (Table 9.1); - to route the IP flows through a specific access, the mobile must ask the home agent to store traffic selection filters for this access. The mobile includes the Flow Identifier (FID) in the Binding Update message (Table 9.2); - the mobile assigns a priority level to each BID. If incoming traffic does not match the traffic selection criteria, then the CoA corresponding to the lowest priority will be used. Table 9.1. Correspondence table between the HoA and CoA addresses Traffic selection IP source/destination address source/destinati