Fast IPv4/IPv6 address acquisition in wireless LANs

We design a methodology for fast IPv4 and IPv6 address acquisition by mobile layer-2 entities in a wireless LAN. The main idea is to do the IP address assignment whenever it is necessary, not after the mobile establishes a layer-2 connection with a new access point. In order to achieve this, we propose to encapsulate the current IP address of the mobile to the association or re-association message in 802.11 WLANs. We present procedures of address acquisition for IPv4, IPv6 and Mobile IPv4, Mobile IPv6. Due to the hidden station problem, the mobile cannot successfully achieve the duplicate address detection (DAD) procedure in IPv6. Our proposal does not require the DAD, so the impact of the hidden station problem in IPv6 address assignment is eliminated. The proposed address assignment procedure, which is executed with layer-2 association, is faster than the existing DHCP-based stateful IP assignment.