當VoIP(Voice over IP)想要商業化並在市場上開始提供通話服務時,都會被國家的法律要求提供犯罪者的電話監聽。在這篇論文所提架構下的合法監聽,是以SIP(Session Initiation Protocol)網路協定為基礎來提出一個架構,另外合法監聽有一些基本的要求,例如不能讓監聽目標發現受到監聽等等,本研究所提架構也能符合這些要求。 For VoIP(Voice over IP) to be commercialized, it must support Lawful Interception(LI) which the Law Enforcement Agency(LEA) of the country asks for. The LI-supported VoIP architecture we proposed in this paper is based on SIP(Session Initiation Protocol). Certain basic requirements are required for a lawful interception system. The architecture we proposed meets the requirements which a lawful interception system must fulfill.