基于遗传算法的代理服务器位置优化研究

Study on Placement Optimization of Web Proxies Based on Genetic Algorithm

针对传统方法难以快速求得Web服务器代理部署问题的满意解,提出了一种基于遗传算法的求解策略.以图论为基础,构建了代理服务器位置优化模型,从Web服务器到客户构成一个树型结构.遗传算法采用二进制编码表示代理的位置,使用单亲交叉算子和单亲变异算子来提高算法的执行速度和进化效率.算法在时间复杂度方面优于传统方法.仿真结果表明,基于遗传算法的求解方案能快速地求出代理服务器位置优化问题的全局近似最优解,并满足实际Web应用的精度要求.

Focusing on the problem of the placement for Web proxies that can not be rapidly solved to get satisfactory results by traditional methods, a novel approach based on genetic algorithm (GA) to optimize the placement of Web proxies was proposed. The model of placement optimization for proxies was constructed on the basis of graphic theory and a tree-like structure was built from Web servers to clients. The GA approach uses binary coding to represent the places and the single parent crossover operator and single parent mutation operator are used to improve its speed and efficiency. The time complexity of this algorithm is known as O (HPN) which is better than traditional methods. Simulation results show that the global approximate optimal solution can be easily and quickly obtained by the proposed method and the precision requirement for practical Web applications is satisfied.