关于下一代网络NGN的设计与实现毕业论文

I摘要本文首先从NGN的定义、特点、网络架构、系统工作流程等几个方面做简单介绍。然后以互联网和传统电信网的安全需求为研究基础，对NGN的安全需求进行分析研究，指出NGN的安全需求是在互联网和传统电信网的安全需求基础上的进一步提升；通过NGN的可靠性与生存性、服务可控性、可用性、信息传递安全等方面来具体分析了NGN的安全问题。通过介绍传统网络的安全解决方案和这些传统解决方案在应对NGN的安全问题中所呈现出的局限性。针对NGN中出现的安全威胁，提出相对比较完整的NGN安全体系框架，并且提出了一些特别的防御措施、合法监听的原理和可行性、入侵检测的基本原理，主要包括面对的威胁、分类检测的方法及其关键技术。本文运用比较全面的视角审视了NGN的安全问题。其中NGN安全体系是本文的创新点。该安全体系在充分考虑了NGN安全需求的前提下，提炼出传统网络的安全解决方案中的精髓，弥补NGN安全上存在的漏洞，解决NGN可能面临的安全威胁。本文同时提出了NGN安全防御的实现思路，重点提出了合法监听在NGN的安全解决方案中的重要性，阐述了合法监听的基本原理、可行性以及所面临的困难,为以后更深入的研究奠定了基础。关键词：NGN，安全需求，安全威胁，安全体系，防火墙，加密，入侵检测，入侵防护，反病毒，合法监听IIAbstractFirstofall,thispapersimplyintroducedthenextgenerationnetwork(NGN),suchasthedefinition,characteristics,networkframesandsoon.Then,thisthesistrytoanalyzeandresearchthesafetyissueswhichNGNmayfaceandthesolveplanscomprehensively.Itincludesfollowingaspects:NGNsaferequests,safetychallengethatNGNmayface,solvingplansofNGNsafetybasedonthetraditionalplans,NGNsafetysystem,NGNdefendmeasures,NGN'slegalmonitorandsoon.ThesecurityrequirementandweaknessarestudieddeeplybasedonthatofInternetandPSTNnetwork.IthasbeenfiguredoutthatthesecurityrequirementofNGNisthecomboofthatofInternetandPSTNnetwork.Throughanalyzingthereliability,existence,servicecontrollabilityandsoon,securityproblemofNGNhasbeenataskdeservingresearch.Thispaperhasconsideredthesecurityrequirementtoabstractthekernelofthesecurityresolveschemeinthetraditionalnetwork;makeuptheleakinNGNsecurity;resolvethepotentialsecurityproblem.But,thetraditionalsecuritysolutionisnotenoughtoresolvealltheNGNsecurityproblems.ThispapersetupanewsecuritysystemforNGNtomeetsuchspecialrequirement,whichisbasedonamountofstudiesonsecuritythreatsfacedbyNGN.Atthesametime,itismentionedthatsomespecialrecoverymeasureandithasbeenputforwardthattherealizationway,especiallytheimportanceofthelegalmonitoringinNGNsecurityscheme.Andthepaperhasexpoundedtheprinciple,fundamental,feasibilityandfacingproblemofthelegalmonitoring.Itwouldbethebaseofdeeperresearch.ThispaperstudiesNGNsecurityproblemsinacomprehensiveview.SuchaconclusionisdrawnthatthetraditionalsecuritysolutioncannotresolveNGNsecurityproblemsentirelybecauseofthedifferencesofrequirement,althoughitisusefulinsomeaspects.Atpresent,itisthegreatestinnovationontheNGNsecuritysystem.Keywords：NGN,securityrequirement,securitythreat,securityframework,firewall,encrypt,IDS,IPS,virus,lawfulmonitor.III目录1前言..........................................................................................................................12下一代网络（NGN）简介........................................................................................22.1基本概念......................................................................................................22.2NGN的特点...................................................................................................32.3NGN的网络架构...........................................................................................42.4NGN的主要技术...........................................................................................53NGN安全解析...........................................................................................................63.1网络安全分析..............................................................................................63.1.1软交换............................................................................................103.1.1.1软交换可以提供哪些主要业务........................................................103.1.1.2软交换业务提供方式........................................................................113.1.1.3软交换与现有网络的互通................................................................133.1.2互联网安全分析............................................................................143.1.3电信网络安全分析........................................................................143.1.4NGN安全分析.................................................................................143.2传统网络安全解决方案分析....................................................................163.2.1防火墙技术....................................................................................173.2.2入侵检测技术................................................................................183.2.3入侵防御技术................................................................................193.2.4应用信息安全保护机制................................................................203.2.5其他相关技术................................................................................213.3传统安全解决方案在解决NGN安全问题的局限性................................224NGN的安全问题.....................................................................................................244.1黑客攻击....................................................................................................244.1.1DOS/DDOS攻击...............................................................................244.1.2其他常见黑客攻击........................................................................254.2VOIP中的安全问题...................................................................................264.2.1VoIP自身的缺陷...........................................................