Research And Realization Of Escalating Conference’s Security Level Based On SIP

Recent years, with the development of Internet technology, the traditional communicationcontent such as audio, video, data has been migrated to the Internet, in order to realize low costand high flexible transmission mode. It has become one of the major development trends in thefield of communication. By reason of increasingly industry competition, each huge telecommuni-cation enterprise has done much research on VoIP technology. Its application and service arehelping customers to save money, improve productivity and rich customer relationship. Thewidespread use of IP phone based on VoIP technology is to promote the development of the in-dustry to becoming more advanced. However, due to its signal is real-time voice which is trans-mitted on the Internet, it naturally inherited the weakness of IP network, such as being attacked bythe hackers and virus. Therefore, for large and medium-sized enterprises customer group, improv-ing the security level of IP phone is urgently needed. This article is based on this big background,exploring how to escalate the security level when the conference is in process. And we provide afeasible solution.Firstly, this article introduces two protocols which support the network conference, that isH.323based on ITU-T and SIP based on IETF. I give the detail information about the functionand network entity of SIP, message format, SDP and so on. Besides, I compared these two proto-cols and highlight the easy-extending characteristic of SIP.For network conference’s signal is transmitted on the Internet, it’s so easy to be vulnerable.This article shows the security threats of VoIP, and introduces the corresponding SIP securitymechanism and method of PKI technology for date encryption. I pay much emphasis on the con-cept, service and composition of PKI. And it’s also one of the most common ways in encryptionfield at present. Combined with the actual situation of the Cisco IP phone use, this article comes from theperspective of the user experience, considering that the security level of conference is determinedby the lowest security of the terminal equipment which is in the conference, thus in order to ensurethe encrypted call, we must enable it to escalate. To solve this problem, we do research on it andput forward a new method, that is, to add one new parameter in the SIP message header and re-construct the SIP state machine. This method can escalate the security level without sacrificing thequality and security of the conference.Finally, this new method is verified on SIPp platform. The experiment shows that it can es-calate the security level of network conference efficiently. In the future, if it can pass the stresstest, it will become one new call feature of Cisco IP phone.