Energy-Efficient Vertical Handover in Heterogeneous Networks

In heterogeneous networks, vertical handover plays a major role in providing seamless connectivity to the mobile users that are passing through different network access technologies and connecting to different point of network attachments. A mobile node scans all of its interfaces to find a suitable network with which it can connect. However, scanning of a large number of networks requires a huge amount of energy thereby the mobile node drains the battery very fast. The Media Independent Handover (MIH), which was introduced by IEEE, to facilitate seamless and energy efficient handover of mobile nodes across heterogeneous networks. The MIH Information Service (MIIS) offers a variety of criteria and services that can be used to avoid network scanning. But sometimes scanning avoidance leads to inconsistent handover, that is, increased handover failure rates. Thus, an optimal network scanning procedure, which can maintain a consistent handover and should consume the energy as least as possible is required. Our proposed work incorporates two additional functional units into MIH - one is responsible for making an optimal network scanning decision (it could be either full scanning, partial scanning, or avoid scanning) and other one is responsible for computing handover decisions by taking both network conditions and user preferences into account. In the second functional unit, we have introduced a utility function based TOPSIS algorithm that computes the handover decisions. Whereas, in principle, MIH users make the handover decision. Almost all of these existing methods suffer from severe ping-pong effect, unnecessary handovers, handover failures, and excess energy consumption due to inaccurate scanning method and ineffective network choice, whereas the performance analysis of our proposed work indicates that the suggested scheme performs better and consumes less amount of energy than existing works.