Wijesekera, DumindaAljarrah, Mohaymen2015-01-292015-01-292015-01-29https://hdl.handle.net/1920/9126DTNs (Delay Tolerant Networks) or opportunistic networks represent a class of networks in which a continuous end-to-end connectivity in the network may not be quite possible. Because DTN is a well-recognized networking concept, it has attracted extensive attentions from both the system designers and also application developers. Security is a major barrier to wide-scale deployment of the DTNs, though it has gained little attention so far. Just like traditional mobile ad hoc networks, the multi-hop transmission and open channel have made DTNs vulnerable to security threats, such as unauthorized access message modification or injection attack. The security characteristics of DTNs include frequent disconnectivity, long round-trip delay, opportunistic routing, fragmentation, as well as limited storage capability and computational delays; make the existing security protocols unsuitable for DTNs. Thus, new security protocols should be implemented; that are stringent and efficient in securing DTNs.enDelay tolerant network (DTN) securityThesis