PIES: Protocol Independent Energy Saving Technique for Mobile Ad Hoc Networks
Carleton University, Ontario, Canada. April 2005.

Mobile communications have become very popular nowadays, especially with the advent of light-weight portable devices that made it convenient to perform many types of tasks while on the move. This has led to rapid advances in the mobile ad hoc network (MANET) field of research. Ad hoc networks are composed of mobile wireless nodes that are generally moving freely within a certain area. These nodes cooperate together in order to route traffic from a source to a specific destination. Several routing protocols have been devised to handle the routing duties within ad hoc networks.

Battery energy is the most scarce resource on which the continued functionality of a mobile ad hoc network depends. Several schemes have been developed to address the issue of energy efficiency with varying degrees of success. In this thesis, we present a new energy-efficient algorithm that we call PIES, which stands for Protocol-Independent Energy Saving. The PIES algorithm presents a new energy saving technique that helps conserve energy that is consumed by the wireless interfaces of the network nodes. PIES is not a routing algorithm, rather it is an algorithm that works in conjunction with existing routing protocols and helps those protocols make decisions regarding energy conservation. PIES functionality conforms to the principle of energy fairness amongst network nodes and does not intervene with the core functionality of the routing protocol. It is a distributed algorithm whose functionality does not depend on any single node or set of nodes within the network. In addition, PIES does not introduce any significant additional traffic or energy costs to the network and its nodes and can be configured to have no additional traffic or energy costs. Our experimental results show that PIES introduces considerable energy savings and works equally well with various categories of routing protocols. This is done in a fair manner to all nodes within the network. Our experiments also show that PIES functionality is consistent with the increase of network traffic and population and increases network lifetime by about 70%.

In addition to the simulation studies, we analyzed the impact of PIES major parameters on protocol performance and validated them through simulation. This provides guidance to network operators in setting these parameters.