Performance Research On The Human Networks And Its Routing Algorithms

With the development of science and technology and the popularity of various wireless communication devices, various types of networks began to emerge, such as human networks, vehicle networks, wireless sensor networks, interplanetary networking, military wireless networks, and so on. These emerging networks have their own communication needs, and also incompatible with each other. As the use of wireless communication and network topology changes frequently, these networks have higher data transmission delay and error rate in the communication process. The current Internet architecture and its protocols can't apply to these emerging networks.As the nodes'distribution is sparse, and the end-to-end connection may not be existed, the communication protocols (such as AODV, DSDV, DSR, et al) which based on the end-to-end in Ad hoc network can't be used in DTN. Especially when the nodes have strict limits on energy and storage, the design of routing algorithms become more difficult. In order to achieve the interconnection between these networks, the international community put forwards a new type of network architecture and its application interfaces, which is called Delay Tolerant Networks.In the Delay Tolerant Networks architecture, the asynchronous message transmission is achieved by adding a bundle layer between the application layer and transport layer, and it uses the way of storage-carry-forward to communicate.As the popularity of wireless mobile communication devices, the human network which is independent of the traditional fixed network infrastructure, has its potential application prospect. Many researchers are dedicated to the approach of the routing algorithms and its applications. There are two main aspects in the research of human network:(ⅰ) Study the characteristic of social relationships, which has guiding significance for the design of routing algorithm in human network. (ⅱ) Research the routing algorithms which are suitable for the human network. As the end nodes in the network have various limits on the resources (including bandwidth, storage space, energy supply, computing power), researchers should take into account these factors in the design of routing algorithms.In this paper, first, we analyze and summary the DTN network model. Then, we put forward the following methods for the research of human network.1. The human network classification based on the routing concern. As people's social mobility, the network topology is changing frequently. A specific routing algorithm is difficult to maintain good performance forever. Therefore, based on the consideration of the routing algorithm's design, we classify the human networks based on the characteristic on the types of links. As the network is determined by the types of links, determining the characteristic of the network links has an important guiding significance for the design of routing algorithms.2. As the mobile devices have energy constraints, we introduce the concept of core node in this paper, and propose the nested spray and wait routing algorithm based on core nodes assisted. The simulation indicated that by increasing the cost of energy consumption at the core-nodes, this routing algorithm has better performances in terms of delivery probability and average delay.3. We use the ONE simulator to build the human network which has vehicles as core nodes assisted. Then we simulate the nested spray and wait routing algorithm, and compare the results with other routing algorithms.