A multi-attribute decision making approach to congestion control in delay tolerant networks

DTNs are prone to congestion due to limited resource on each node and unpredictable end-to-end delay. We aim to develop an effective congestion control mechanism in this paper. For this purpose, we first identify a list of major congestion factors by analyzing the causes of congestion. We then model the congestion control as a multiple attribute decision making problem (MADM), in which the weight of congestion factors is measured by an entropy method. To solve this problem, we present a MADM-based congestion control mechanism that determines a set of forwarding messages and its transmission order on each encounter event. Moreover, we design a buffer management scheme that deletes messages whose removal would incur the least impact to the network performance when the buffer overflows. Extensive real-trace driven simulation is conducted and the experimental results finally validate the efficiency of our proposed congestion control mechanism.