Huang Yongfeng

Steganalysis of Compressed Speech

Based on the analyzing of the redundancy of coded parameters in G.723.1, a novel approach to detect hiding information is proposed in this paper. By using the statistical value of increaser entropy, this scheme can not only detect hidden messages embedded in compressed speech, but also estimate the embedded message length accurately .The experimental results show that the proposed scheme is effective.

Research on methods to identify the opinion leaders in internet community

With the rapid development of WEB2.0, Internet forums have become an information exchanged platform where netizens can freely express their opinions. In Internet consensus environment, it is very important to appropriately control and lead the consensus and the opinion leaders play critical roles in Internet community. This paper, by combining the characteristics of Internet forums, established a PageRank Model to identify the opinion leaders based on the influence of linguistic contents and the sentiment tendentiousness. The PageRank Model adopts the product of the influences of the contents and sentiments (i.e., integrated influence) as the weighted value of two ID numbers and achieves the PR value via the PageRank calculation, thereby identifying the opinion leader of the forum. Tests have verified that the original PageRank vector of the Inlink has its advantages, compared with other methods, the ID of the opinion leaders articles identified by the PageRank Model can cover 80% of the forum IDs, which is in compliance with the 2-8 law. Therefore the algorithms based on the PageRank Model can identify effectively the opinion leaders in Internet community.

Implementation of Steganography Based on HOOK

So far the steganography based on streaming media is widely studied,but rarely of it is based on instant communication tools. This paper improved the previous steganography which was implemented by HOOK based on instant communication tool. The improved methods contain adaptive sockets functions hooking(ASFH) and speech recognition based on socket functions,which can be generally applied in the instant communication tools,at last we implemented these methods in the covert channels of Bol SipPhone and Gtalk. Experimental results presents that the methods are actually feasible in the communication process. Which broaden the scope of steganography based on the streaming media and have a good realistic significance.

The key technologies in multi-call processing of the VolP Gateway

Bacause Gateway serves many users, there are some related problems to be solved, such as the allocation and management of multiple calls, the synchronization of multiple threads, the state transference and time-out processing. To solve these problems, key technologies in our implementation will be proposed, which are important to the stability and efficiency of the Gateway. At last, the test of our Gateway is shown and analyzed.

Security issues in VoIP based on H.323

We first discusses some threats to VoIP system and H. 323 architectures designed for VoIP communications on security point of view. Continues with presenting security requirements of VoIP, and explaining the essential security constraints surrounding a seccessful VoIP deployment. Finally, suggests some strategies to implement the security and encryption functions of VoIP system based on H. 323.