在VoIP環境中的彈性化監聽方案

Abstract

由於IP網路的蓬勃發展，再加上更便宜的通訊費用和更多樣化的加值服務，VoIP的技術成為傳統PSTN網路的替代方案。但是在提供通訊服務之外，電信業者也必須提供合法的監聽管道，提供政府能夠執行合法的監聽。本篇論文在現行的網路基礎架構下，提供彈性化的VoIP監聽方案。我們提供了一套名為FIVE System的彈性化監聽方案，提供五種不同的監聽模式，並針對不同的模式做評估與分析。我們提供的五種監聽方式分別為：The Rogue Back to Back Interception, The Rogue SIP Proxy Interception, The SIP Proxy attached Interception, Remote Attack Interception and Port Mirroring Interception。每一種不同的監聽模式都可應用在某一種網路區域，而且各有其優點。藉由我們FIVE System的協助下，政府單位可以選擇最適合的方式來做合法的監聽。我們也建構了VoIP的環境來驗證我們的FIVE System，所得到的實驗結果更可以提供未來使用FIVE System的參考。而各種彈性化的方案，提供使用者根據不同的網路類型選擇方案，或者使用混合的方式得到最佳的網路監聽效果。

The VoIP is growing rapidly due to the popular of the Internet network. The VoIP can provide the cheaper communication fee and various value-add services. It can replace the traditional PSTN network. But the VoIP network should also provide the lawful interception function for government. This thesis based on the current VoIP network architecture to provide a flexible interception system. The FIVE system is a flexible interception system. And provide five different interception models for the lawful interception. The five models are The Rogue Back to Back Interception, The Rogue SIP Proxy Interception, and The SIP Proxy attached Interception, The Remote Attack Interception and Port Mirroring Interception. Each interception model have their advantages. The government can do the flexible interception by using our FIVE system. We also setup the VoIP environment to do the experiment According to our experimental results. Government can choose the best solution to adapt the different network environment. And the hybrid mode can provide the best VoIP lawful interception.