An Integrated Framework for Seamless Soft Handoff in Mobile Ad Hoc Networks
Patel,Mitesh
US Army CECOM
LI,Jason
Intelligent Automation, Inc.
Staikos,Aristides
US Army CECOM
McAuley,Tony
Telcordia Technologies, Inc.
Luo,Song
Intelligent Automation, Inc.
Gerla,Mario
University of California, Los Angeles
Das,Subir
Telcordia Technologies, Inc.
The multiplicity of existent wireless networks and technologies creates the need for techniques that can allow devices to automatically transit between the network landscapes. In this paper, we present an integrated architecture for seamless soft handoff in mobile ad hoc networks, where various managers residing on multiple layers are proposed to handle handoff issues in a cross-layer and cooperative manner. At the link adaptation layer, the virtual interface provides link transparency to the upper layers and session management is handled at the interface manager. The device and system monitor reports information about the wireless interfaces, and the policy manager incorporates various aspects of factors for comparing interfaces. The handoff is optimized to execute policy-based decisions to keep network traffic delay and traffic congestion to a minimum. At the network layer, essentially most IP-based ad hoc routing protocols can be accommodated, and the architecture can naturally host QoS protocols, like Differentiated Services with admission control. At the transport layer, the transport manager is instructed by the interface manager to adapt the transmission rate according to the new wireless link. Finally at the application layer, the security manager handles various aspects of security concerns, including defense against man-in-the-middle attacks. We have shown that our approach can deliver low packet loss, low latency, and smooth handoff solutions with minimum packet overhead. Further, our approach is resistant to node mobility thanks to the intelligent link management scheme. Our research on IEEE 802.21 shows that current Media Independent Handover (MIH) may either serve as a component in our integrated architecture, or this research will pioneer Ad-Hoc-MIH specifications. In conclusion, our work represents the first complete solution that provides seamless handoff in ad hoc networks with minimum service disruption.
Jason H. Li received his B.E. and M.S. degrees in Electrical Engineering from the Tsinghua University, Beijing, China in 1993 and 1996 respectively, and his Ph.D. degree in Electrical and Computer Engineering, from the University of Maryland at College Park, USA in 2002 majoring in computer communication networks.
He is currently a senior research scientist at Intelligent Automation, Inc., Rockville, MD, USA. Prior to that, he was a senior research scientist in Hughes Network Systems. His research interests lie in the general area of computer communication networks, including network protocols, network security, network management and control, and distributed software agents.
Dr. Li is a member of the IEEE and the ACM.