ABSTRACT

Dela y tolerant networks are kind of ad-hoc networks in which end-to-end connected path does not exist between sender and receiver. Mobility of nodes highly effects the communication in delay tolerant networks. Due to network partitions traditional routing mechanisms are not viable so, DTN relies on store and forward strategy to route messages. One of the major objectives of delay tolerant network is to provide conductivity in those areas which were considered to be unapproachable such as to extend the concept of internet to space to interconnects planets and provide communication in underwater. In order to accomplish the mentioned objective some routing mechanism must be devised. Therefore, routing in delay tolerant network has become one of the hot research areas. Since last few years many researchers have explored challenging issues with respect to routing in DTN.

There are two major objectives of our thesis work. First. we investigated performance of some well-known DTN routing protocols using various mobility models and provide a detail comparative analysis of these protocols in term of various parameters such as delivery ratio, overhead and latency at different buffer sizes, variable number of nodes, different transmission ranges and mobility models. We also surveyed various routing protocols for DTN proposed by different researchers and provide a detailed classification based on various features such as flooding or controlled flooding. historical or no­ historical. single copy or multiple copy and location aware or location unaware. Second, we proposed an algorithm called "Grid based routing algorithm" for delay tolerant network, which is basically an improved version of epidemic routing protocol. Grid based routing algorithm make use of the idea of location infonnation of nodes in order to control flooding and number of message transmission in network. It is assumed that in grid based routing,


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