Soft load balancing over heterogeneous wireless networks

Ongoing next-generation networks are expected to be deployed over current existing networks in the form of overlayed heterogeneous networks, particularly in hot-spot areas. Therefore, it will be necessary to develop an interworking technique, such as load balancing, to achieve increased overall resource utilization in the various heterogeneous networks. In this paper, we present a new load-balancing mechanism termed "soft" load balancing, where the Internet Protocol (IP) traffic of a user is divided into subflows, each of which flows into a different access network. The terminology of soft load balancing involves the use of both load-sharing and handover techniques. Through a numerical analysis, we obtain an optimal load-balancing ratio (LBR) to determine the volume of traffic delivered to each network over an overlayed multicell environment. Using the optimal LBR, a more reliable channel transmission can be achieved by efficiently reducing the outage probability for given user traffic.