Date Added: Feb 2010
This paper considers the problem of routing packets across a multi-hop network consisting of multiple sources of traffic and wireless links with stochastic reliability and a broadcast nature. Opportunistic routing relies on the following principle. Each packet transmission can be overheard by a random subset of receiver nodes among which the next relay can be selected opportunistically. This paper surveys and revisits known opportunistic routing policies: Opportunistic variants of shortest path routing, such as Extremely Opportunistic Routing (ExOR) and Stochastic Routing (SR), select the relay on the shortest path to the destination. The opportunistic variants of backpressure routing, such as DIVersity BAckpressure Routing (DIVBAR), select the relay with the least queue backlog.