Abstract

The VPN is the abbreviation of the Virtual Private Network, Chinese translates for the virtual appropriation net.The meaning of the Virtual Network contain two, on is a VPN is an establishment at the existing physics network on, with the concrete network structure of the physics network irrelevant, the customer did not need to concern the physics network and equipmentses generally;Two is the VPN what hour of the customer usage VPN see is a can establish in advance the definite dynamic state of network.The meaning of the Private Network also has two, on is a public network that expresses that the VPN establishment can arrive in all customers up, especially Internet, also include the PSTN, frame relay, ATM etc., in time of a be constitute by the special line particularly net inside set up the VPN, opposite VPN this is also a" male net";Two is a VPN and will build up the appropriation network to be called the privately owned network perhaps, insure the network conjunction of provide the safety, it must have a few key functions:Attestation, visit the control, encrypt and data integrity.

The key technology for VPN is the security of data over a public network. The three types of security: authentication, encryption and encapsulation, forms the foundation of virtual private networking. However, authentication, encryption and encapsulation can be performed by many different technologies. In addition, these three sets of technologies can be combined in different ways.

Keywords    Frame relay    authentication    encapsulation

目    录

摘  要. I

Abstract.. II

第一章   VPN的主要内容. 1

1.1 什么是VPN. 1

1.2 VPN组成 3

1.3 VPN的特性 4

1.4 VPN的用途 6

1.5 VPN的优势 7

第二章  基于Windows的VPN方案. 9

2.1 历史 9

2.2 Windows VPN协议 9

2.3 Windows 内可以建立三种VPN. 11

2.4 Windows VPN相关问题 12

2.5 Windows VPN方案优势：初始成本最低的VPN. 14

2.6 应用方向 14

第三章  基于IPsec的VPN方案. 17

第四章  基于SSL的VPN方案. 21

第五章 VPN实例. 25

实例一：远程移动办公安全方案 25

实例二：分公司与总公司联网 28

实例三：安全平台 30

参考文献. 34

第一章   VPN的主要内容

1.1 什么是VPN

VPN是Virtual Private Network的缩写,中文译为虚拟专用网。Virtual Network的含义有两个，一是VPN是建立在现有物理网络之上，与物理网络具体的网络结构无关，用户一般无需关心物理网络和设备；二是VPN用户使用VPN时看到的是一个可预先设定义的动态的网络。Private Network的含义也有两个，一是表明VPN建立在所有用户能到达的公共网络上，特别是Internet，也包括PSTN、帧中继、ATM等，当在一个由专线组成的专网内构建VPN时，相对VPN这也是一个“公网”；二是VPN将建立专用网络或者称为私有网络，确保提供安全的网络连接，它必须具备几个关键功能：认证、访问控制、加密和数据完整。

　　一个网络连接一般由三个部分组成：客户机、传输介质和服务器。VPN也一样，不同的是VPN连接使用隧道作为传输通道，靠的是对数据包的封装和加密。

　　VPN是一种快速建立广域联接的互联和访问工具，也是一种强化网络安全和管理的工具。

　　VPN建立在用户的物理网络之上、融入在用户的网络应用系统之中。VPN技术涵盖了多个技术专业,不同应用领域所适用的技术和产品有很大差异。

　  VPN技术仍在快速发展中。