In most of the mobile network which are of wireless network at many times they do not have the complete path between the source and destination. There are many networks real that follow these conventional rooting methods such as military networks, vehicular ad hoc networks, and wildlife tracking sensor networks. Because they establishes complete end- to- end paths before any data are been send. In the case of flooding based schemes have the high probability of delivery, which wastes more energy.

The dealing with such a networks many researches have been done which can significantly degrade their performance. So that the overhead of the flooding based schemes are been reduced in large. New routing schemes have been introduced where these schemes spray a message copy into the network and routes each copy independently to the destination. It also good performance under large number of scenarios, and also shows how to no of copies to be sprayed and how to distribute these copies between the systems in the network.

Efficient Routing in Intermittently Connected Mobile Networks paper also discuss about the topics like delay tolerant networks, ad hoc network, intermittent connectivity and routing. The spray phase can be defined as for every message originating at the source node, nmessage copies are been initially spreadforwarded by the source and possibly by the other nodes receiving a copyto ndistinct relays. Direct transition is performed Ifthe designationis not found in the spraying phase, then each of the nnodes carrying a message copy i.e. it will only forward the message to its destination is mentioned as the Wait phase.

Efficient Routing in Intermittently Connected Mobile Networks paper also discusses about the stability of spray and wait. This paper proposes two efficient multi- copy schemes called spray and wait which overcomes the shortcomings of flooding based and other existing schemes.