vpn An integrated MIP

An integrated MIP client function (client-basedmobility) supports a variety of MIP extensions specificfor WiMAX and 3GPP2 EV-DO/HRPD; for MIP version 4(MIPv4), it also supports both foreign agent-based CoA(as per WiMAX and 3GPP2) and collocated CoA (typical for Wi-Fi interworking) configurations. An integrated DHCP client supports additional DHCP options(e.g., carrying user identity or requesting an ANDSFserver IP address) necessary for interworking with network-based mobility, as well as the acquisition of localIP addresses for CMIP with collocated CoA.CM also controls policy enforcement functions andbuffering algorithms in the user plane, in conjunction with the make-before-break inter-technology handover procedures.Seamless interworking algorithms. A seamlessinter-technology handover experience is achieved viaa combination of several algorithms implemented inthe UE as listed below. Specific details of the algorithms' realization are outside the scope of this paper.All algorithms are implemented in the CM, except forintelligent buffering, which is implemented in thebearer (data) plane and controlled by the CM.• Enhanced network discovery and selection. The goalsof this algorithm include maintaining active RATwith a signal quality within the policy-definedboundaries; timely selection of a new RAT to minimize the possibility of the currently active RATsignal deteriorating below an acceptable level andimpacting the quality of application sessions;avoiding a ping-pong effect of frequent back-andforth handovers between RATs at RAT coverageboundaries; and enforcing both static anddynamic SP policies. This algorithm makes use ofsignal quality monitoring via an interface withdevice adapters, in conjunction with associatedpower and battery life policy