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voip关于nat穿越问题的解决方法,voip关于nat穿越问题的解决方法全文30页约20000字 图文并茂 内容翔实摘 要voip(voice over internet protocol)是一种以ip电话为主,并推出相应的增值业务的技术。voip最大的优势是能广泛地采用internet和全球ip互连的环境,提供比传统业务更多、更好的服务。它也是目前in...
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VOIP关于NAT穿越问题的解决方法
全文30页约20000字 图文并茂 内容翔实
摘 要
VoIP(Voice over Internet Protocol)是一种以IP电话为主,并推出相应的增值业务的技术。VoIP最大的优势是能广泛地采用Internet和全球IP互连的环境,提供比传统业务更多、更好的服务。它也是目前Internet应用领域的一个热门话题。
VoIP的大规模应用将极大地增加对IP地址的需求。当前VoIP主要使用NAT技术来解决地址匮乏的问题。随之而来却是NAT穿越的问题。基于H.323、SIP等协议的VoIP应用需通过信令消息中的IP地址和端口参数来实现目的地寻址,因此NAT穿越时不仅需要对TCP/UDP层的端口信息以及IP层的源地址和目的地址进行变换,还需对IP包载荷中的相关地址信息进行变换。NAT穿越是目前开展VoIP业务最大的障碍,迫切需要解决。
本文深入分析了VoIP中NAT穿越问题的现有解决方案,然而,当这些解决方案应用于不同的网络拓扑时都有着显著的利弊,以至于我们只能根据不同的接入方式来应用不同的方案。所以我们目前需要一种综合的足够灵活的方法,使之尽可能的解决大部分情况下的NAT穿越。
本文的创新点在于通过采用端口预测的机制来推断出对称NAT的下一个分配地址,使得STUN协议可以穿越大部分对称NAT和所有别的NAT。该方案无需现有NAT设备作任何改动,并支持多个NAT串联的网络环境,同时对STUN协议自身不能穿越对称NAT的问题做出了有益的探索和实践。研究和实践表明,本文所提出的STUN改进方案能够有效的解决典型的SIP穿越NAT问题,为VoIP的大规模应用提供了帮助。
关键词: IP网上的语音通信 会话初始化协议 UDP对NAT的简单穿越 网络地址转换
Abstract
This thesis deeply analyzes current solutions of NAT traversal on the VoIP. However, these solutions present obvious advantages VoIP is a technology that mostly utilized in IP phone, and relevant value-added services. The most advantage of VoIP is that can make use of the global IP internetworking environment, to provide the more and more the better and better services than traditional PSTN network. It is also the hot research field of Internet.
The widely application of VoIP increases the requirement of a large number of IP addresses. VoIP mainly uses NAT to solve this. Accompanied by the matter of NAT traversal .The VoIP application based on H.323 and SIP uses the IP address and port in the message body of signaling to route. So besides transforming the TCP/UDP layer port and IP layer address, VoIP NAT traversal needs to transform parts of the payload of IP packages. NAT traversal is the biggest drawback of VoIP application and it should be solved soon.
This thesis deeply analyzes current solutions of NAT traversal on the VoIP. However, these solutions present obvious advantages and disadvantages depending on the topological conditions of the network. So we need a complete solution that is flexible enough to through most of NAT in different network topology.
全文30页约20000字 图文并茂 内容翔实
摘 要
VoIP(Voice over Internet Protocol)是一种以IP电话为主,并推出相应的增值业务的技术。VoIP最大的优势是能广泛地采用Internet和全球IP互连的环境,提供比传统业务更多、更好的服务。它也是目前Internet应用领域的一个热门话题。
VoIP的大规模应用将极大地增加对IP地址的需求。当前VoIP主要使用NAT技术来解决地址匮乏的问题。随之而来却是NAT穿越的问题。基于H.323、SIP等协议的VoIP应用需通过信令消息中的IP地址和端口参数来实现目的地寻址,因此NAT穿越时不仅需要对TCP/UDP层的端口信息以及IP层的源地址和目的地址进行变换,还需对IP包载荷中的相关地址信息进行变换。NAT穿越是目前开展VoIP业务最大的障碍,迫切需要解决。
本文深入分析了VoIP中NAT穿越问题的现有解决方案,然而,当这些解决方案应用于不同的网络拓扑时都有着显著的利弊,以至于我们只能根据不同的接入方式来应用不同的方案。所以我们目前需要一种综合的足够灵活的方法,使之尽可能的解决大部分情况下的NAT穿越。
本文的创新点在于通过采用端口预测的机制来推断出对称NAT的下一个分配地址,使得STUN协议可以穿越大部分对称NAT和所有别的NAT。该方案无需现有NAT设备作任何改动,并支持多个NAT串联的网络环境,同时对STUN协议自身不能穿越对称NAT的问题做出了有益的探索和实践。研究和实践表明,本文所提出的STUN改进方案能够有效的解决典型的SIP穿越NAT问题,为VoIP的大规模应用提供了帮助。
关键词: IP网上的语音通信 会话初始化协议 UDP对NAT的简单穿越 网络地址转换
Abstract
This thesis deeply analyzes current solutions of NAT traversal on the VoIP. However, these solutions present obvious advantages VoIP is a technology that mostly utilized in IP phone, and relevant value-added services. The most advantage of VoIP is that can make use of the global IP internetworking environment, to provide the more and more the better and better services than traditional PSTN network. It is also the hot research field of Internet.
The widely application of VoIP increases the requirement of a large number of IP addresses. VoIP mainly uses NAT to solve this. Accompanied by the matter of NAT traversal .The VoIP application based on H.323 and SIP uses the IP address and port in the message body of signaling to route. So besides transforming the TCP/UDP layer port and IP layer address, VoIP NAT traversal needs to transform parts of the payload of IP packages. NAT traversal is the biggest drawback of VoIP application and it should be solved soon.
This thesis deeply analyzes current solutions of NAT traversal on the VoIP. However, these solutions present obvious advantages and disadvantages depending on the topological conditions of the network. So we need a complete solution that is flexible enough to through most of NAT in different network topology.