Energy Efficient Beaconing Control Strategy Based on Time-Continuous Markov Model in DTNs

In delay-tolerant networks (DTNs), unpredictable mobility leads to the uncertainty of network topology, and it is hard to maintain an end-to-end connection from the source to the destination. To realize the forwarding of the messages, beaconing is used to detect the contact probabilities. However, beaconing frequency not only influences the detection probability of the available communications but is concerned with the energy consumption rate as well. The higher the beaconing frequency is, the faster the energy is consumed. The energy consumption leads to the reduction of the network survival time, due to the lack of energy supply. In contrast, the lower the beaconing frequency is, the less frequently available communications are detected, which also leads to a decrease in delivery rate. Therefore, it is meaningful to find out the most suitable beaconing frequency in specific DTNs. In this paper, we propose an energy efficient dynamic beaconing control strategy in energy-constrained DTNs (DBCEC) based on the time-continuous Markov model. Six different dynamic function forms are, respectively, used to control the beaconing frequency. Simulations based on the synthetic mobility pattern and real mobility traces are conducted in the Opportunistic Network Environment (ONE), and the results show that DBCEC-E achieves a better delivery rate without affecting the average delay and the overhead ratio, compared with other beaconing control strategies.