对于分布式的大型企业来说,其各地分支机构之间的联系是日常工作的重要组成部分。这种远程的通信联系,以前主要是依靠电信部门的长途电话交换网,虽然比较稳定可靠,但价格也是比较高的,随着长途通信量的急速增长,企业的通信成本也大幅攀升,企业为降低成本,迫切需要市场提供一种兼具实用性和经济性的远程通信手段。IP网络的迅猛发展为远程通信提 For distributed large enterprises, the links between their branches around the country is an important part of their daily work. This long-distance communication connection was mainly based on the long-distance telephone exchange network of telecommunications departments. Although relatively stable and reliable, the price is relatively high. With the rapid growth of long-distance traffic, the communication costs of enterprises have also risen sharply. Enterprises Reduce costs, the urgent need for the market to provide a practical and economical means of telecommunications. The rapid development of IP network for the telecom