Aim to the problem of resource allocation

a dynamical algorithm of allocating resource was proposed.The algorithm dynamical migrates virtual node

which based on the average load discrepant degree of physical nodes and the tolerant load discrepant degree of substrate network.It will choose a proper host according to the values of synthetically impact factor

that reduce impact on the delay of virtual link and the bandwidth of physical link.Simulation result shows that the algorithm can improve load balance on physical nodes

and reduce negative impact on delay and bandwidth.