Design And Simulated Implementation Of Handoff Mechanisms Based On Swarm Intelligence With Abc Supported

With the rapid development of network technology, Internet has become one of the most important components of people's work and life. Enjoying the high-quality network service anywhere and anytime in NGI (Next Generation Internet) has become people's necessary requirement. Therefore, NGI must support ABC (Always Best Connected) and provide QoS (Quality of Service) guarantee. In this thesis, handoff mechanisms with ABC supported in NGI are designed based on such a background.In order to ensure that users can access to network with the best way, indetermination of network information, user's QoS requirements, user's preference, user's utility, service provider's utility and fairness of both sides are all considered. Because the state information of NGI is not exact enough, aiming at this problem, the network model and mathematic model are designed tohandle the inexact parameters. In order to incarnate the fairness between users and network providers, game theory of micro-economics is introduced to calculate the utility for the user and network provider. Meanwhile, Nash equilibrium is used to take into account the benefits of both sides to assure the support to ABC. Not only utilities of both sides should be optimized while the QoS requirements are satisfied, but also the users'preference ought to be taken into consideration. There are five swarm intelligence algorithms, namely, the niche PSO (Particle Swarm Optimization) algorithm, multi-PSO algorithm based on optimal mutation, artificial fish swarm algorithm based on mixture of mutation operator and SA (Simulated Annealing), population migration algorithm, and food-chain algorithm based on artificial life, to find the optimal solution to choosing the most reasonable distribution scheme of network access.In this thesis, the above handoff model and algorithms are implemented based on NS2 (Network Simulator 2) environment. The simulation results show that the mechanism is feasible and effective. Not only users'preferences about network and provider are taken into account while basic QoS requirements are satisfied, but also interest of users and network providers are taken into consideration. In conclusion, the mechanism can support the handoff with ABC supported in NGI.