A One-Pass Method of MIP Registration by WLAN Host Through GPRS Network.

This paper proposes a new technique for Mobile IP (MIP) registration by WLAN host (WH) through GPRS network. The home agent (HA) of WH resides in external IP network. The gateway GPRS support node (GGSN) provides foreign agent (FA) functionality for WH in GPRS. After successful attach with GPRS network, WH needs two mandatory passes for MIP registration with HA. First it establishes PDP (packet data protocol) context in GPRS network and then it sends MIP registration request (MRR) to FA at GGSN. This causes a large delay for handoff from WLAN to GPRS. We propose a one-pass technique of MIP registration through GPRS network to reduce the handoff delay. We transport MIP-registration request of WH in the information field of activate-PDP-context request message to GGSN. Thus MIP registration message reaches GGSN before completion of PDP context establishment. This technique reduces the control signaling for handoff from WLAN to GPRS. We observed from simulated results that proposed one-pass technique reduces handoff delay by 18% compared to handoff delay in two-pass method. Keywords: 3G, GPRS, loose coupling, MIP, tight coupling, UMTS, WLAN. [ABSTRACT FROM AUTHOR]