报告日期Date:  2017年4月24日

报告时间Time:  上午10:30

报告地点Location:  数计学院2号楼309会议室

报告人:Dr. Yuhong Liu 刘宇宏  博士

Assistant Professor, Department of Computer Engineering, Santa Clara University, U.S.A

美國 加州 圣塔克拉拉大学 计算机工程系 助理教授

Title:    Security, Privacy and Trust in Online Social Media

报告标题:   网络社交媒体的安全、隐私及信誉机制

Abstract：The prosperity of online social media encourages individual users to generate and share diverse digital contents online. This huge amount and rapidly growing data is playing an increasingly important role in influencing people’s daily lives and decisions. However, it has also raised many security, privacy and trust issues.

The simplicity of creating arbitrary contents online by individual users makes the trustworthiness of information questionable. More important, profit driven malicious attacks are emerging rapidly aiming to mislead the general public’s opinions and decisions. Take online reputation system as an example. In such systems (e.g., Amazon rating platforms), users can provide their ratings/reviews based on past experiences, and later other users can refer to those ratings/reviews to make their online purchasing or downloading decisions. Many companies aggressively boost their reputation by manipulating these online ratings either by themselves or through some “rating companies”. Taobao, the largest retail website in China, has identified these rating boosting services (“water army”) as a severe threat. This talk will mainly focus on attack and defense studies on fake information detection in online social media through signal processing and machine learning tools.

中文摘要：网络社交媒体的繁荣极大的促进了个人用户在计算机网络上生成以及共享各种信息与数据。由此而产生的大量的数据正在对用户在日常生活中的各种决定起着越来越重要的作用。然后，这些数据与信息的共享也带来了很多安全、隐私以及信任的问题。

首先，由于任何用户都可以非常简单的生成信息，这些信息的可信度变得非常难以控制。更重要的是，利益驱动下的恶意用户也可以非常容易的篡改信息，从而误导大众的意见以及决定。用网络信誉系统来举个例子。在这些系统中，比如亚马逊的产品投票系统，或者淘宝的用户投票系统，用户可以根据他们对产品的使用体验来提供对于产品、其他用户或者服务的评价，而后来的其他用户可以根据这些评价来做出他们的购买或下载决定。很多商家利用这一点，通过提供虚假评价来提高自己的信誉值，从而吸引更多的真实用户。淘宝，中国最大的个人电子商务平台，也已经认定虚假投票是对电子信任机制的很大的威胁。这个报告将主要从攻击和防御两方面探讨对于网络社交媒体上虚假信息的检测。

Biography简历

Education and Award: Yuhong Liu is currently an assistant professor at Department of Computer Engineering Santa Clara University. She received her B.S. and M.S. degree from Beijing University of Posts and Telecommunications in 2004 and 2007 respectively, and the Ph.D. degree at University of Rhode Island in 2012. She is the recipient of the 2013 University of Rhode Island Graduate School Excellence in Doctoral Research Award. Her work on securing online reputation systems received the best paper award at the IEEE International Conference on Social Computing 2010 (acceptance rate = 13%).

Research Interests: With expertise in trustworthy computing and cyber security, her research interests include three major directions: online social network security, trust management in cyber-physical systems and trustworthy cloud computing. Specifically, her work borrows the concept of trust from sociology and applies it to the cyber world, where it is called digital trust, to indicate how much confidence one entity has about whether the other entity will perform a certain action or possess a certain property. Trust related security research, which guides entities to detect misbehavior, to take actions by avoiding risks, and to cooperate with other entities, plays a unique and indispensable role in making the cyberspace secure and trustworthy.

Professional Experiences: She is an associate editor of IEEE Signal Processing Magazine e-Newsletter since 2014, a guest editor of IEEE STCSN e-Letter special issue on \"Security and privacy issues in online social network\" 2014. She is the membership chair of IEEE Special Technical Community on Social Networks (STCSN) since 2013, and committee member of IEEE STC Executive Committee Board since 2015. She has served as the finance chair and registration chair of IEEE Global Conference on Signal and Information Processing (GlobalSIP) 2015, the general chair of Human and Social Computing Symposium at IEEE Computer Society International Conference on Computers, Software & Applications (COMPSAC) 2016. She also served as the technical program committee for the fourth ASE International Conference on Social Informatics 2015, IEEE GlobalSIP-Workshop on Information Forensics and Security 2014, and ASE/IEEE International Conference on Social Computing 2012. She also serves as a reviewer on a number of top-tier journals.

More information about her research can be found at https://www.scu.edu/engineering/faculty/liu-yuhong/.

刘宇宏博士，于中国北京邮电大学取得信息工程学士学位（2004年）、及信号处理专业硕士学位（2007年），于美国罗德岛大学取得计算机工程博士学位（2012 年）。现任职于Santa Clara University计算机工程系助理教授。她曾获得2013年罗德岛大学优秀博士毕业论文奖，2010年IEEE Socialcom会议(文章录取率13%) 最佳论文奖。

她的研究方向主要包括计算机及网络安全，信任机制模型及应用。目前，主要进行的项目研究包括社交网络以及云计算的安全、隐私及信任机制。具体而言，她的研究借鉴了社会科学中信任的概念，并把它应用到计算机系统及网络中来代表两方之间的关系，即一方对另一方即将做出的行动以及拥有的属性有多大的信心。信任机制相关的计算机安全研究，可以被用来帮助计算机系统或网络提前检测攻击行为，归避风险，以及增强多方之间的合作，在保障系统及网络的安全方面发挥着不可替代的作用。

她于2014年开始担任IEEE Signal Processing Magazine e-Newsletter的副编辑，还曾是IEEE STCSN e-Letter 关于网络社交媒体安全与隐私special issue的客座编辑。她于2013年开始担任IEEE STCSN会员主席，2015年开始担任IEEE STC 执行委员会委员。她是2015年IEEE GlobalSIP会议的财务主席和注册主席，2016年IEEE CompSAC会议关于社交计算及人机交互专题的主席。她还曾担任过多个会议的技术委员会成员，比如ASE Social Informatics 2015, IEEE GlobalSIP 2014信息安全专题研讨会，ASE/IEEE Socialcom 2012。她还是很多顶级期刊杂志的审稿人。