Delay Tolerant Networks Considering Pedestrian Crowds The research and development of technology for maintaining an information networks, which are an important lifeline in the event of a natural disaster such as an earthquake, is indispensable in large metropolitan areas. One of the characteristics of urban disasters is the occurrence of evacuees who form large crowds due to population congestion. Under such circumstances, delaytolerant networking, which has conventionally been considered an effective means of communication at times of disaster, does not always work sufficiently. We propose a routing method that reduces the number of message transfers significantly compared to the conventional methods by focusing on the movement characteristics of the pedestrians. Moreover, the effectiveness of the proposed method is evaluated by computer simulation.

An improved Spray and Wait routing protocol for Delay Tolerant Network Delay Tolerant Network(DTN) is a wireless network where source cannot have a handshake with the destination and source has to use a routing known as opportunistic routing to deliver the message to the destination. One of the most widely used routing protocol in DTN is Spray and Wait(SnW) routing protocol and there are a lot of methods to complete the spray phase, most popular is Binary SnW. In this paper, we are proposing a modified version of Binary SnW protocol referred as Hexago SnW. In this approach, we used hexagonal series instead of binary series. The comparison of Hexago SnW with other existing approaches shows that Hexago SnW gives better performance than others in term of overhead ratio, delivery ratio etc. In simulation, two groups of moving objects are used to show the working and performance evaluation of our proposed routing technique.