Research On Congestion Control Of Dense Business Based On Wavelength Alternation In IONs

With the rapid growth of IP services,it becomes a key issue to be considered about how to control more reasonably and allocate resources more flexibly for intelligent optical networks to make it efficient to carry IP services.Therefore,this thesis makes a research of intelligent optical networks congestion control problem focused on dense business,and researches how to minimize network blocking possibility and maximize the utilization of network resources by proper control.This thesis proposes some design works through the researches of congestion control in intelligent optical networks for multiple services and analyzing impact of blocking possibility in dense business network environment.First,it is easy to form resource conflicts because the wavelength is used again for dense business in distributed intelligent optical networks,the thesis designs a dynamic routing algorithms based on wavelength alternation strategy(for short D_WA)by introducing wavelength cost Cλ on the total weight of route.Then,the thesis designs a link prediction algorithm based on wavelength alternation strategy(for short LP_WA)by introducing the definition of critical links and route factor β on the total weight of route because of the large time complexity of the traditional RWA and the link overloaded.Finally,this thesis paper designs a link prediction and soft preemption algorithm based on wavelength alternation combining soft preemption strategy(for short LPSP_WA)by further congestion location and rerouting for the blocked business because of the imbalance of dense business space.It will release the resource to high priority business on base of the transmission quality of existing services and existing another path for the preempted business.Finally,this thesis simulates these three congestion control algorithms,and then compares and analyzes the performance with other solutions.Simulation results show that:the wavelength alternation strategy is more effective to avoid resource conflicts in the dense business network,compared without the strategy and adaptive optimization algorithm,blocking possibility decreased by about 25%,resource utilization increased by nearly 20%and it is better for non-dense business.While LP_WA algorithm adjusts factor β and wavelength cost Cλ to make the link load mean increase by nearly 9 percent,and the resource utilization and blocking possibility are better compared to the adaptive optimization algorithm.The soft preemption strategy improves the network performance on average by 10%,and optimizes the allocation of resources further and improves congestion control performance.