ABSTRACT
To reduce and control unwanted traffic over the Internet, technologies such as firewalls, Intrusion Detection System, and Intrusion Prevention System have been widely used, achieving certain positive effects. However, the ubiquitous Internet has also made it much easier for spammers to spread unwanted traffic to a large number of Internet users. Moreover, it is capricious due to the fact that spammers are adopting increasingly sophisticated methods and applying new strategies. Web spam refers to the immoral manipulation of search engine results that intentionally mislead search engines to rank certain web pages higher than they deserve. The web spam can be classified into link spam, content-based spam, and spam that utilizes hiding techniques. Link spam boosts the ranking of a target web page by making use of a link-based ranking algorithm, such as PageRank. A good privacy-preserving solution should be able to protect personally identifiable information and ensure data secrecy, anonymity, and unlinkability in a certain degree.
