An algorithm optimization was made with improved simulated annealing algorithm aimed at data transmission strategy of streaming media system in P2P networks.According with global layout

a mathematic model have been estab-lished for data transmission strategy of streaming media system in P2P networks named VMDTSA-P2P

which com-pletely have considered the affection of both the out-bandwidth and the available time

and take them as the object func-tion for getting the optimum solution.It also optimized the solutions with improved simulated annealing algorithm.Compared with traditional data transmission strategies

this improved algorithm accelerates the speed of new nodes choose the data provider from its partner nodes when there are lots of users and insures the solution of the data provider is approximate the best.Thus

the play delay of the streaming media system is decreased and the quality of video playback is increased.By realizing it in a simulated P2P system

the accuracy and the efficiency were both verified in the simulation.