Multi Access Data Network Connectivity and IP Flow Mobility in Evolved Packet System (EPS)

Release-8 (Rel-8) EPS (Evolved Packet System) introduced a multi access 3GPP system where different heterogeneous access systems are connected to a common core network. However, in the system, the subscriber cannot communicate using multiple accesses simultaneously. Mobile devices with multiple interfaces are becoming commonly available and the set of applications running on the devices is diversifying with some applications suited to run over 3GPP access systems and other applications well suited to run over some other complementary access systems. In these circumstances, it has become important to allow dynamic allocation of different IP flows to different access systems as per their requirements, so that the user experience can be enhanced while the connectivity cost for the operator can be optimized. This paper has studied and analyzed the scenarios, requirements and solutions related to simultaneous connectivity to multiple access networks and IP flow mobility, and proposed necessary enhancements to existing 3GPP specifications for EPS.