【正文】 Infoics稱，2022 年全球 MPLS服務(wù)收入為 130億美元，比 2022年增長了 20%。MPLS VPN服務(wù)通常提供許多網(wǎng)狀網(wǎng)絡(luò)，任何站點都能夠與其它站點連接。要使用幀中繼技術(shù)達到這個目的就需要在每一個站點與每一個其它站點之間建立昂貴的虛擬線路。MPLS 能夠讓用戶避免復(fù)雜性和更多的成本。MPLS還支持各種價格的多種服務(wù)質(zhì)量，為企業(yè)用戶提供更多的選擇，可以為不重要的通訊購買價格便宜的 VPN服務(wù)。但 MPLS VPN使用價格相對較貴，當企業(yè)規(guī)模大、總部分部之間需要交換信息量大的時候可以考慮使用 VPN。VPN ( Virtual Private Network)是一種對網(wǎng)絡(luò)數(shù)據(jù)進行封包后再加密傳輸?shù)募夹g(shù)，可以在互聯(lián)網(wǎng)上建立起臨時時、安全的連接，并傳遞私有數(shù)據(jù)，能夠達到私人網(wǎng)絡(luò)的安全用戶級，從而利用互聯(lián)網(wǎng)構(gòu)筑起企業(yè)專有網(wǎng)絡(luò)，是企業(yè)內(nèi)部網(wǎng)絡(luò)的向外延伸，可以給用戶提供到專用網(wǎng)絡(luò)所必須具備的網(wǎng)絡(luò)功能，但是其本身又不是一個獨立自由的物理網(wǎng)絡(luò)系統(tǒng)。VPN的核心技術(shù)是“隧道”(Tunneling)技術(shù)，它的核心過程是在源局域網(wǎng)和公網(wǎng)的對接日位置，將數(shù)據(jù)作為負載封裝在公網(wǎng)上傳輸?shù)臄?shù)據(jù)格式里，在目的局域網(wǎng)和公網(wǎng)的對接日部分將已經(jīng)封裝的數(shù)據(jù)再解封，取出負載。封裝后的數(shù)據(jù)包在互聯(lián)網(wǎng)上傳遞過程中經(jīng)過的邏輯路徑被稱為“隧道” 。隧道技術(shù)允許VPN的數(shù)據(jù)流經(jīng)由路由，再通過網(wǎng)絡(luò)，而且不論生成該數(shù)據(jù)流的是哪一種類型的網(wǎng)絡(luò)或者是設(shè)備。某種意義上講，VPN 的操作可以獨立于其它網(wǎng)絡(luò)操作協(xié)議，隧道內(nèi)的數(shù)據(jù)流或者數(shù)據(jù)包可以是 IP、甚至是 IPX以及 AppleTalk等不同類型的網(wǎng)絡(luò)數(shù)據(jù)包。所以 VPN必須通過跨越于 IP協(xié)的公用網(wǎng)絡(luò)共同構(gòu)建起安全專用通道實現(xiàn)公用網(wǎng)絡(luò)的私用傳遞。三、課題的主攻方向本課題主要是探討如何在大型企業(yè)網(wǎng)絡(luò)中使用的 VPN，對大型企業(yè)網(wǎng)絡(luò)中使用的 VPN的應(yīng)用方案進行規(guī)劃、設(shè)計與實現(xiàn)。在大型企業(yè)部署 VPN要考慮到實用性、可擴展性、便利性、可靠性、先進性、經(jīng)濟合理性，要先全面進行規(guī)劃，然后再逐步實施。先要調(diào)查企業(yè)的需求，然后對企業(yè)的需求進行分析，選擇合適的 VPN協(xié)議類型及相關(guān)設(shè)備，并完成對設(shè)備的配置，最后測試網(wǎng)絡(luò)。四、工作的主要階段、進度及完成時間～ 初步確定選題、寫作論文提綱～ 查閱相關(guān)文獻～ 寫開題報告、準備開題答辯 開題答辯～ 在老師指導下進行論文修改、定稿 論文打印、裝訂、填寫相關(guān)表格，準備答辯～ 畢業(yè)答辯參考文獻[1]龍成梁, VPN技術(shù)及在大型企業(yè)集團中的應(yīng)用[J].武漢科技學院學報,2022,23(2):4447[2]戴剛,文信翔, 在企業(yè)中應(yīng)用的研究[J].網(wǎng)絡(luò)安全技術(shù)與應(yīng)用,2022,4:6567[3][J].科技信息,2022,28:266267[4] 技術(shù)在企業(yè)信息管理中的應(yīng)用研究[J].中小企業(yè)管理與科技,2022,6:218219[5]梁靜宇, VPN 和 IPSec VPN企業(yè)應(yīng)用分析[J].科學之友,2022,11:45[6] VPN及其在安全遠程訪問中的應(yīng)用[J].四川理工學院學報(自然科學版),2022,18(1):5759[7]董云耀, VPN試驗網(wǎng)的組建和測試分析[J].計算機工程與設(shè)計,2022,26(6):14721477[8]陶國芳, IPSec VPN的配置實現(xiàn)[J].微計算機信息,2022,22(9):134136[9]、入侵檢測與 VPN[M].:北京郵電大學出版社,2022[10]王振宇, 路由器 VPN配置常見問題及解決方法[J].硅谷,2022,22:3334[11]李紅, VPN技術(shù)的比較與應(yīng)用探析[J].硅谷,2022,17:181182[12]G Shorrock, C IP Secure — a Managed Firewall and VPN Service[J].BT Technology Journal,2022,19(3):99106[13]董小國, SSL VPN的研究與設(shè)計[J].中國科技信息,2022,4:9497[14] VPN[EB/OL]./,2022725[15]Laurent Ciarletta, MiJung Configuration for VPN Using Active XML[J].Lecture Notes in Computer Science,2022,3751:173180專業(yè)譯文原文：《Cisco Certified Network Associate Study Edition 》的第 740747 頁（作者：Todd Lammle 出版社：Wiley Publishing, Inc. ）英語原文：I hope you39。re ready to learn about the nuts and bolts of Inter Protocol version 6 (IPv6), because you39。re going to get the rub on it in this chapter! You should have a solid hold on IPv4 by now, but if you think you could use a refresher, just page back to Chapter 3, Subting, Variable Length Sub Masks (VLSMs), and Troubleshooting TCP/IP. And if you39。re not crystal clear on the address problems inherent to IPv4, you really should review Chapter 11, Network Address Translation (NAT)” People refer to IPv6 as the nextgeneration Inter protocol, and it was originally created as the answer to IPv439。s inevitable, looming addressexhaustion crisis. Though you39。ve probably heard a thing or two about IPv6 already, it has been improved even further in the quest to bring us the flexibility, efficiency, capability, and optimized functionality that can truly meet our ever increasing needs. The capacity of its predecessor, IPv4, pales in parisonand that39。s the reason it will eventually fade into history pletely. The IPv6 header and address structure has been pletely overhauled, and many of the features that were basically just afterthoughts and addendums in IPv4 are now included as fullblown standards in IPv6. It39。s seriously well equipped, poised, and ready to manage the mindblowing demands of the Inter to e. I promisereallyto make this chapter pretty painless. In fact, you might even find your self actually enjoying itI definitely did! Because IPv6 is so plex yet elegant, innovative and chockfull of features, it fascinates me like some weird bination of a brandnew Lambhini and a riveting futuristic novel. Hopefully you39。ll experience this chapter as the cool ride that I did writing it!Why Do We Need IPv6?Well, the short answer is, because we need to municate, and our current system isn39。t really cutting it anymorekind of like how the Pony Express can39。t pete with airmail. Just look at how much time and effort we39。ve invested in ing up with slick new ways to conserve bandwidth and IP addresses. We39。ve even e u p with Variable Length Sub Masks (VLSMs) in our struggle to overe the worsening address drought It39。s realitythe number of people and devices that connect to works increases each and every day. That39。s not a bad thing at allwe39。re finding new and exciting ways to municate to more people all the time, and that39。s a good thing. In fact, it39。s a basic human need. But the fore cast isn39。t exactly blue skies and sunshine because, as I alluded to in this chapter39。s introduction, IPv4, upon which our ability to municate is presently dependent, is going to run out of addresses for us to use. IPv4 has only about billion addresses availablein theory, and we know that we don39。t even get to use all of those. There really are only about 250 million addresses that can be assigned to devices. Sure, the use of Classless InterDomain Routing (CIDR) and Network Address Translation (NAT) has helped to extend the inevitable dearth of addresses, but we will run out of them, and it39。s going to happen within a few years. China is barely online, and we know there39。s a huge population of people and corporations there that surely want to be. There are a lot of reports that give us all kinds of numbers, but all you really need to think about to convince yourself that I39。m not just being an alarmist is the fact that there are about billion people in the world today, and it39。s estimated that just over 10 percent of that population is connected to the Interwow! That statistic is basically screaming at us the ugly truth that based on IPv439。s capacity, every person can39。t even have a puterlet alone all the other devices we use with them. I have more than one puter, and it39。s pretty likely you do too. And I39。m not even including in the mix phones,