An Adaptive Traffic Distribution Scheme for CMT based on Lotka-Volterra Model in Multihomed Networks

CMT(concurrent multipath transfer) can increase throughput and transmission efficiency in multihomed networks. However, it is still an important challenge about distributing traffic adaptively into multiple access networks. Based on LV(Lotka.Volterra) model, we propose an adaptive traffic distribution scheme. In the scheme, two competition modes are concluded, multiple S.D(source.destination) streams competition for bandwidth of one path and multipath competition for traffic between each multihomed S.D host pair. Actually, each access network can establish a path for S.D pairs. So, in the first mode, each path is analogous to a predator, and overall traffic in a multihomed host is analogous to prey. Then, each path has to compete for the traffic by path information, e.g., bandwidth and congestion level. In the other one, if several S.D pairs pass through a shared path simultaneously, they will compete for bandwidth of the path. Here, each S.D pair is analogous to a predator, and the bandwidth of the common path is analogous to the prey. At last, compared with other three schemes, uniform traffic distribution, greedy path selection, random path selection in OPNET simulator, the proposed scheme can perform better onreducing file transmission time and increasing network throughput in FTP service.

An Integrated Architecture for Vertical Handover Management

Recent advances in hardware technology have made it possible for mobile devices to interface with multiple networks of different types. In this paper, an IEEE 802.21 Media Independent Handover (MIH) based handover management architecture containing four modules is proposed and the multihoming technology is adopted to achieve Make-Before-Break vertical handover. Then the paper presents the performance analysis of the architecture and simulation in ns-2. The results substantiate the effi cacy of the architecture in improving the handover performance signifi cantly compared with the traditional Mobile IPv6 (MIPv6) based vertical handover. Besides, we design and implement this handover management architecture in our test-bed. The experimental results in a real network environment show that our proposed architecture can not only support the Make-before-break handover, but also guarantee the scalability because of the modulized design.

Secured Efficient Fast Handover Multihoming Based NEMO+ (SEFMNEMO+) for Vanets

Vehicular Ad Hoc Network (VANET) is an emerging technology in which mobility management, continuous connectivity and security on data transmission between vehicles with high speed or during the change of topology of the network acts as a challenging exploration issue of Intelligent Transportation System (ITS) applications. This paper aims to formulate a ubiquitous connectivity to nodes by keeping the established connections before and after handover thereby minimizing the delay, packet loss and provide secured acknowledgement for handover. The Secured Efficient Fast Handover Multihoming Based NEMO+ (SEFMNEMO+) framework helps to optimize the NEMO+ scheme that supports multihomed network, handover and security. The predictive policy exchangemethod is used to update the future handover for minimizing the overhead delay and packet loss. The multihomed feature in NEMO+ supports efficient handover mechanism between heterogeneous networks when VANET connection fails. Public key cryptography provides the secure acknowledgement before handover i.e., the acknowledgement is encrypted with digital signature.