Fast distributed dominating set based routing in large scale MANETs

Hierarchical routing techniques have long been known to increase network scalability by constructing a virtual backbone. Even though MANETs have no physical backbone, a virtual backbone can be constructed by finding a connected dominating set (CDS) in the network graph. Many centralized as well as distributed algorithms have been designed to find a CDS in a graph (network). Theoretically, any centralized algorithm can be implemented in a distributed fashion, with the tradeoff of higher protocol overhead. Because centralized approaches do not scale well and because distributed approaches are more practical especially in MANETs, we propose a fast distributed connected dominating set (FDDS) construction in MANETs. FDDS has message and time complexity of O(n) and O(Δ²), where n is the number of nodes in the network and Δ is the maximum node degree. According to our knowledge, FDDS achieves the best message and time complexity combinations among the previously suggested approaches. Moreover, FDDS constructs a reliable virtual backbone that takes into account (1) node's limited energy, (2) node's mobility, and (3) node's traffic pattern. Our simulation study shows that FDDS achieves a very low network stretch. Also, when the network size is large, FDDS constructs a backbone with size smaller than other well known schemes found in the literature.