随着企业信息化的发展,企业已经不再满足只是能在自己的局域网内访问信息资源,他们需要突破限制,实现总部和各个分支机构的互联,实现移动员工可以随时随地地访问企业内部的局域网,甚至合作伙伴也能访问企业的部分信息资源。Internet的发展和电信网络的不断完善,使这一切都成为可能。但是,随之而来便产 With the development of enterprise information, enterprises are no longer satisfied with just access to information resources within their own LAN, they need to break through the restrictions and achieve the headquarters and various branches of the Internet, to achieve mobile employees can access anytime, anywhere within the local area network , And even partners can access some of the company’s information resources. The development of the Internet and the continuous improvement of the telecommunications network make all this possible. However, the consequent will be produced