Proactive mobile IPv6 for context-aware all-IP wireless access networks

A major challenge in building ´all-IP´ wireless access networks, besides the use of IP as the unifying layer, relates to transparency of the IP hand off process as the mobile node (MN) transits across heterogeneous wireless network domains in IPv6 mobility management. Transparency in IP handoffs, however, must be effected in two separate contexts: IP-addressing and (re-)connection latency. Excessive delays during an IP handoff degrades the seamlessness of IP transmission between the MN and its peers. In this paper, we assess experimentally how transport protocols such as TCP and subsequently applications can under-perform as the MN performs an IP handoff between two heterogeneous wireless networks, namely WLAN and GPRS. We discuss why dynamic establishment of IP context-state can help address these limitations that seem inherent in heterogeneous environments. To this end, we evaluate by means of simulations, the proactive mobile IPv6 as a means of effecting advance context-state establishment, between candidate points of attachment, for the purposes of reducing/eliminating IP handoff delay while providing IPv6 handoff selectivity.