*********************************
There is now a CONTENT FREEZE for Mercury while we switch to a new platform. It began on Friday, March 10 at 6pm and will end on Wednesday, March 15 at noon. No new content can be created during this time, but all material in the system as of the beginning of the freeze will be migrated to the new platform, including users and groups. Functionally the new site is identical to the old one. webteam@gatech.edu
*********************************
Atlanta, GA | Posted: August 24, 2007
Graduate student Anirudh Ramachandran's work on filtering spam usingnetwork-level properties will appear at the ACM Conference on Computerand Communications Security (CCS), ACM's top security conference, atthe end of October. Ramachandran and his advisor, Assistant ProfessorNick Feamster, have been working with Professor Santosh Vempala todevelop next-generation spam filtering techniques.
Spam is becoming increasingly virulent as it makes use of images andPDFs to evade content-based filters. To make matters worse, spammersare sending spam from "fresh" machines every day, which makes itdifficult to maintain static blacklists of known bad senders.
To get a step ahead, the researchers have taken a different approach:
rather than filtering spam based on content or an ephemeral identity ofthe sender (e.g., an IP address), the researchers have invented a newtechnique called "behavioral blacklisting". Behavioral blacklistingaims to learn and "fingerprint" spammers' sending patterns---forexample, the set of recipients a particular sender is targeting---andblacklist senders based on their sending behavior, rather than a fixedidentity.
The researchers developed their first behavioral blacklisting techniqueby applying Professor Vempala's novel spectral clustering algorithms,which have also successfully been applied to other areas (e.g., Websearch).
