In delay tolerant networks (DTNs), the network may not be fully connected at any instance of time, but connections occurring between nodes at different times make the network connected through the entire time continuum. In such a case, traditional routing methods fail to operate as there are no contemporaneous end-to-end paths between sources and destinations. This study examines the routing in DTNs where connections arise in a periodic nature. Various levels of periodicity are analyzed to meet requirements of different network models. We propose various routing algorithms for periodic connections. Our proposed methods can find routes that can guarantee earliest delivery and minimum hop count. We evaluate our routing schemes via extensive simulation experiments and also compare them to some other popular routing approaches proposed for delay tolerant networks. Our evaluations show the feasibility and effectivenes of our schemes as alternative routing methods for delay tolerant networks.  Keywords
To meet the needs of different network models, Mergenci and Korpeoglu REF provided different routing mechanisms for different types of periodic connections to ensure the earliest delivery time and the minimum number of hops.
Routing in delay tolerant networks with periodic connections
EURASIP Journal on Wireless Communications and Networking
Computer Science