Abstract
Delay –disruption Tolerant networks are sparse wireless network which is recently being used by the existing /current network for the purpose to connect devices or the underdeveloped area of the world that works in challenging environment. In DTN there majority of time does not exist the total path from source to target which is leads to the difficulty of how to route the packet in such environment. A communications network which is accomplished of storing packets temporarily in intermediate nodes, until the time an end-to-end route is re-established or regenerated is known as a delay tolerant networks. Routing in such network is very difficult and for that different routing protocols are developed. In this Survey paper we discuss about various routing Strategy and at the end compared the different routing protocol with their various performance metrics.
Keywords: Delay tolerant networks (DTNs), Erasure coding, Replication, Routing.