VANET Networks are one of the main next generation wireless networks which are envisaged to be an integration of homogeneous and heterogeneous wireless networks. The inter-networking of these wireless networks with the Internet will provide ubiquitous access to roaming network users. However, a seamless handover mechanism with negligible handover delay is required to maintain active connections during roaming across these networks. Several solutions, mainly involving host-based localized mobility management schemes, have been widely proposed to reduce handover delay among homogeneous and heterogeneous wireless networks. However, the handover delay remains high and unacceptable for delay-sensitive services such as real-time and multimedia services. Moreover, these services will be very common in next generation wireless networks. Unfortunately, these widely proposed host-based localized mobility management schemes involve the vehicle in mobility-related signalling hence effectively increasing the handover delay. Furthermore, these schemes do not properly address the advanced handover scenarios envisaged in future wireless networks. This paper, therefore, proposes a VANET mobility management framework utilizing cross-layer design, the IEEE 802.21 future standard, and the recently emerged network-based localized mobility management protocol, Proxy Mobile IPv6, to further reduce handover delay.
A Cross-Layer Design Based on Geographic Information for Cooperative Wireless Networks