Modelling And Evaluation For Opportunistic Networks Based On Being Restricted Time And Space

With the emergence of intelligent devices,the application of opportunistic networks is also expanding.Simulation has become an important means to study the performance of communication protocols or routing algorithms because of being difficult to build large-scale network.The basis of the simulation experiment is mobility model that can simulate the movement of the nodes.The movement of nodes shows different features due to the variety of nodes and the complexity of the environment.It is necessary to build different mobility models to describe the movement of nodes in different scenarios.Research shows that different mobility models have a great impact on network performance,such as routing protocol,network connectivity,etc.Therefore,in order to accurately simulate the characteristics of nodes in different scenes,different mobility models need to be built.In real networks,nodes that are carried by humans have human mobility characteristics.Research shows that human movement has spatial and temporal properties.However,the proposed mobility models do not respond well to these properties of the nodes.In order to solve this problem,the novel mobility model with spatial and temporal properties and the method of evaluation are proposed.The main contents of this paper are as follows.(1)Modelling based on being restricted time and space.The state of nodes is divided into free state and restricted state according to the spatial and temporal properties of nodes.The nodes have different behaviors in different states.Different parameters are used to simulate these properties of the nodes.(2)Analysis steady distribution of the novel model.The model of node state transformation is built on the basis of Markov theory.(3)Exploring the evaluation method of the mobility model.First of all,we put forward thirteen evaluation indicators from four aspects.Secondly,the evaluation method of qualitative and quantitative is proposed based on fuzzy comprehensive evaluation method.(4)Analysis performance of the novel model.The performance of the mobility model is analyzed with ONE and Proposed evaluation method.The results show that the novel mobility model has the authenticity and rationality.