Wireless networks have been developed with various demands such as voice over IP (VoIP) and multimedia services. And mobile devices become smaller and do more computation and communications with high technological innovations. In the case of ad hoc communications, a mobile node is responsible for forwarding others’ data as well as sending/receiving its own data. Therefore much attention should be paid to energy issue in terms of energy balance as well as energy consumption.
With respect to energy balance, there have been active researches proposing energy-aware routing algorithms for mobile ad hoc networks. They take advantage of energy-related metrics to find the most energy-balancing route in route discovery procedure. However there have been few works touching the energy balance during data transmission which is addressed in this paper.
This paper presents a new mechanism named $\emph{Node Alarming Mechanism (NOAL)}$ where an intermediate node having low energy alarms its status to others. With NOAL, we propose two routing algorithms: $\emph{LEAR with NOAL (LENOAL)}$ and $\emph{FEAR with NOAL (FENOAL)}$ that can balance the energy consumption among mobile nodes in ad hoc networks. They are based on DSR and FSR and belong to different routing categories such as reactive and proactive protocols, respectively. Therefore it is possible to compare the energy performances between different types of routing protocols as well as to evaluate them under a type of routing protocol in the proposed algorithms. The simulation study shows that LENOAL and FENOAL can balance energy consumption over networks by 21-36% depending on the network conditions.