At present, there are few methods for the design and optimization of scale-free network routing algorithms. This paper studied the relationships between classic local routing algorithms, network topology, and nodes processing speed. At first, a few relationships were revealed and proved theoretically and experimentally. And then, by using such relationships, the influence of parameters on the performance of routing algorithms was analyzed. Based on such analysis, some rules on the design and optimization of dynamic routing algorithm for BA network were proposed. Simulation experiments have shown that, compared with classic local routing algorithms, the dynamic local routing algorithm based on these principles can effectively improve the performance of BA scale-free networks.