Delay/disruption Tolerant Networks (DTNs) provide connectivity in those networks which lack continuous connectivity or considerable delays like that of terrestrial mobile networks, military ad-hoc networks, sensor or planned network in space. They lack in an end-to-end path between Source and Destination resulting in long variable propagation delays. The Internet Protocols do not operate properly in these networks, thus raising a variety of new challenging problems in this area. The DTN effectively improves the network communications where the connectivity in the network is intermittent or is prone to disruptions. Routing in DTNs is challenging because of long and frequent time durations of non-connectivity. There are several routing approaches that have been proposed with strategies ranging from flooding to forwarding approaches. In this paper these protocols are analyzed based on the quantitative data gathered by simulating each protocol in ONE simulator environment. The performance is discussed and compared for different routing protocols and results are discussed for different performance metrics.