Research On The Technology Of Route Optimization In Nested Mobile Networks

NEMO has a promising application future in the next generation network, as it handles mobility of a set of mobile nodes in an aggregate way and provides continuous Internet connectivity, meeting the demands of people to communicate everywhere, at anytime. However, NEMO suffers from severe route optimization problems, especially when it becomes nested or multi-homed. The main shortages of the existing route optimization schemes are as follows: Firstly, route optimization schemes are lack of effective cost analysis model. Secondly, the current schemes can't combine with the construction characters and application environment, resulting in high costs in the process of route optimization. Lastly, reasonable strategies taking the multi-homed and security problems into consideration are in demand. Therefore, this dissertation is devoted to researching on the route optimization problem in Nested NEMO.Based on the study of route optimization problem, the dissertation established a novel cost analysis model for route optimization in Nested NEMO firstly, and then, proposed two route optimization schemes on the basis of the cost model.The main achievements of this dissertation are as follows:1. A cost analysis model for route optimization in Nested NEMO (CAMRO) is proposed. From the aspect of cost spending, the singaling cost and header overhead are used to be measurement of route optimization performance. The model defines the cost function of data routing and calculates the total cost of the communication in Nested NEMO. CAMRO not only can analyze the communication cost for route optimization schemes, but also can be used as performance evaluating metrics.2. An adaptive routing optimization scheme based on cost function (ARO-CF) is proposed. In the scheme, depending on the communication and mobility pattern, the communication of Nested NEMO is divided into three models, including binding update model, data routing model and balanced communication model. Different routing optimization strategies are chosen to balance the signaling cost and the header overhead to minimize the total communication cost in each model. The CAMRO analysis and simulation results show that the scheme can shorten tunnel length and transmission delay, achieve the minimum cost of the communication in each communication model and have good adaptability for network topology dynamic changes.3. A load balancing route optimization scheme based on path-cost model (LBR-PM) is proposed. The scheme establishes path-cost model for Multihomed nested-NEMO firstly, then depending on the density of path-cost, a dynamic source routing algorithm is used for path choosing and traffic balancing to minimize the total cost of data routing in Multihomed nested- NEMO. The simulation results show that the scheme can solve the route optimization problem, realize reasonable choose in multiple transmission paths and achieve the minimum cost of the communication in Multihomed nested-NEMO.