論文標(biāo)準(zhǔn)WORD格式排版

目　　錄
第一章vpn的工作原理 4
第二章vpn的特點(diǎn)及vpn的分類 5
2.1 vpn的特點(diǎn) 5
2.2 vpn的分類 6
2.2.1 Intranet VPN 6
2.2.2 Access VPN 7
2.2.3 Extranet VPN 8
第三章IP VPN 的安全機(jī)制 8
3.1認(rèn)證技術(shù) 9
3.2 加密技術(shù)簡(jiǎn)介 9
3.3 密鑰的交換與管理 10
第四章IPSec 及VPN 10
第五章隧道協(xié)議和基本隧道要求 10
5.1 令牌卡（Tokencard）支持 11
5.2 數(shù)據(jù)壓縮 11
5.3 數(shù)據(jù)加密 11
5.4 密鑰管理 11
5.5 多協(xié)議支持 11
第六章 典型實(shí)例 vpn拓?fù)鋱D 12
第七章 VPN發(fā)展趨勢(shì) 12
第八章 IP VPN市場(chǎng) 13
8.1 Internet成為了全球信息基礎(chǔ)設(shè)施 14
8.2 全球經(jīng)濟(jì)一體化 14
8.3 IP VPN為企業(yè)和服務(wù)提供商實(shí)現(xiàn)了雙贏 14
結(jié)論 14
致 謝 15
參考文獻(xiàn) 16

摘要：VPN是指虛擬專用網(wǎng)絡(luò)，英文全稱是Virtual Private Network。它不是真正的專用網(wǎng)絡(luò)，是利用公有網(wǎng)絡(luò)（利用Internet）將多個(gè)私有網(wǎng)絡(luò)通過一定方法連接起來。使用公用網(wǎng)絡(luò)進(jìn)行連接的好處是可以降低通信及設(shè)備的成本。
在網(wǎng)絡(luò)中的計(jì)算機(jī)可以通過IP地址，能夠直接進(jìn)行通信的。但是這些計(jì)算機(jī)的網(wǎng)絡(luò)是不能直接互聯(lián)的，原因就是這些私有網(wǎng)絡(luò)和公有網(wǎng)絡(luò)使用了不同的協(xié)議和地址空間等等，這說明了一個(gè)問題：私有網(wǎng)絡(luò)和公有網(wǎng)絡(luò)是不兼容的。VPN的原理就是在私有網(wǎng)絡(luò)和公有網(wǎng)絡(luò)之間建立一個(gè)條專用的通道。讓私有網(wǎng)絡(luò)之間的通信經(jīng)過計(jì)算機(jī)或網(wǎng)絡(luò)設(shè)備打包然后通過公有網(wǎng)絡(luò)的專門的通道進(jìn)行傳輸，然后傳到對(duì)端之后進(jìn)行解包，還原為私有網(wǎng)絡(luò)之后將網(wǎng)絡(luò)信息轉(zhuǎn)發(fā)到私有網(wǎng)絡(luò)中。這樣對(duì)于兩個(gè)私有網(wǎng)絡(luò)和公有網(wǎng)絡(luò)就像普通的通信電纜，而在公有網(wǎng)絡(luò)上的計(jì)算機(jī)或網(wǎng)絡(luò)設(shè)備就能很好的同信了。
由上面可知vpn中要解決兩個(gè)很重要的問題就是在網(wǎng)絡(luò)傳送中的安全問題還有傳輸之后的解包問題。而且在傳送中還要解決之間的傳輸之間的協(xié)議問題
關(guān)鍵詞：虛擬專用網(wǎng) 安全協(xié)議 VPN、IP SEC、隧道技術(shù)、加密技術(shù)、L2TP

Virtual Private Network
Abstract ：VPN is to refer to suppositional special use network , the English full name is Virtual Private Network. It is not real special use network , is to make use of the public network (make use of Internet) to will be the private network more by the fact that certain method links up. Using the public network to carry out connected benefit is to be able to reduce communication and the equipment cost.
Can pass IP address in computer in network , be able to be in progress directly communicating by letter. These computer networks have been to be able to not interconnection directly but , cause has it is these private networks and public network to have used different agreement and address space etc. , this has explained a problem: The private network and the public network are no compatible. The VPN principle it is between private network and public network to build a special-purpose passage. And then dodge the communication between private network a computer passes or network equipment packs and then transfer by the fact that network special public passage is in progress, conduct arriving at the parcel carrying out a solution on end afterwards, restore for the private network believes a network afterwards
May need to resolve very important two problems it is safe problem in delivering in the network to there are still in knowing vpn by higher authority transmission afterwards solve package of problems. And transmission between wanting to solve too in transference between agreement problem
Keywords: Suppositional special use net safety agreement VPN , IP SEC , tunnel technology, encrypt the technology , L2TP