發(fā)布時間：2018-01-31 06:40

  本文關鍵詞： SIP NAT穿越 UDP打洞 STUN HTTP隧道　出處：《南京航空航天大學》2014年碩士論文　論文類型：學位論文

【摘要】：SIP協(xié)議作為下一代網(wǎng)絡最重要協(xié)議之一,已被廣泛應用于VoIP系統(tǒng)中。為了解決公網(wǎng)IP地址匱乏以及網(wǎng)絡安全等問題,企業(yè)網(wǎng)一般都使用了NAT和防火墻技術。雖然NAT技術可以很好的解決IP地址匱乏問題,但SIP協(xié)議本身并不具有穿越NAT的能力,因此NAT對VoIP通信造成了不利影響。目前,現(xiàn)有的SIP穿越NAT的解決方案都存在一定的局限性,各有優(yōu)缺點。本文提出一種綜合STUN和HTTP代理的NAT穿越新方案,該方案通過STUN技術自動判斷網(wǎng)絡環(huán)境類型,針對不同的網(wǎng)絡環(huán)境分別設計了具體的穿越流程。對于錐形NAT,該方案結合UDP打洞技術對其穿越;對于其它限制嚴格的NAT,該方案利用STUN技術和HTTP代理實現(xiàn)穿越。本方案可以穿越包括UDP受阻型等限制嚴格的NAT/防火墻,且不需要更換現(xiàn)有的NAT設備。為了更合理的分配系統(tǒng)資源,本文提出了SIP服務端系統(tǒng)資源優(yōu)化方案,由統(tǒng)計數(shù)據(jù)得知客戶終端發(fā)起通話請求的規(guī)律,計算出系統(tǒng)在現(xiàn)有設置下的各項性能指標。設定系統(tǒng)性能的期望指標,計算出系統(tǒng)各時段滿足期望的資源數(shù)量,結果表明各時段需要的資源數(shù)量遠小于原系統(tǒng)設置的數(shù)量,優(yōu)化了系統(tǒng)對資源的分配。為了解決系統(tǒng)服務高峰期產(chǎn)生的服務質(zhì)量下降問題,本文進一步的對系統(tǒng)資源做了動態(tài)優(yōu)化,降低了用戶等待服務時間,提高了系統(tǒng)的性能。為了驗證本方案的功能,在各類NAT網(wǎng)絡環(huán)境中進行了試驗,并做了抓包分析。利用SIPp測試軟件對其進行性能分析,結果表明本方案具有較好的性能和穩(wěn)定性。通過與其它方案對比,表明本方案可以穿越更多類型NAT/防火墻,能夠更合理的分配系統(tǒng)資源,具有很好的應用價值。
[Abstract]:As one of the most important protocols in next generation network, SIP protocol has been widely used in VoIP system. In order to solve the problem of lack of IP address in public network and network security and so on. Enterprise networks generally use NAT and firewall technology. Although NAT technology can solve the problem of IP address scarcity, SIP protocol itself does not have the ability to traverse NAT. Therefore, NAT has a negative impact on VoIP communication. At present, the existing solutions of SIP traversing NAT have some limitations. This paper presents a new NAT traversal scheme combining STUN and HTTP agents, which automatically determines the type of network environment through STUN technology. Specific traversing flow is designed for different network environments. For conical NATA, this scheme combines UDP drilling technique to traverse it. For other restricted NATs, the scheme uses STUN technology and HTTP proxy to implement traversing. This scheme can traverse the Nat / firewall which includes the UDP blocked type and so on. And do not need to replace the existing NAT equipment. In order to allocate system resources more reasonably, this paper proposes a SIP server system resource optimization scheme, from the statistical data to know the customer terminal call request rule. The performance indexes of the system under the existing settings are calculated. The expected index of the system performance is set, and the number of resources that meet the expectations in each time period of the system is calculated. The results show that the amount of resources needed in each period is much smaller than that of the original system, and the allocation of resources is optimized. In order to solve the problem of service quality decline caused by the peak period of system service. This paper further optimizes the system resources, reduces the waiting time of users, and improves the performance of the system. In order to verify the function of this scheme, experiments are carried out in various NAT network environments. The results show that this scheme has good performance and stability. It shows that this scheme can traverse more types of NATT / firewall, and can allocate system resources more reasonably, so it has good application value.
【學位授予單位】：南京航空航天大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TP393.04
，

本文編號：1478488