Title: Ultrafast Security Event Processing for SIEM Systems Abstract This talk describes a new technique for fast submatch extraction for regular expressions and its application to improving the performance of event processing in Security Information and Event Management (SIEM) systems. A capturing group is a syntax used in modern regular expression implementations to specify a subexpression of a regular expression. Given a string that matches the regular expression, submatch extraction is the process of extracting the substrings corresponding to those subexpressions. Our experimental results show an approximate 2.5 fold improvement over Java's backtracking based regular expression library on a typical SIEM problem. Bio Dr. Bill Horne is a Research Manager in the Cloud and Security Lab of Hewlett-Packard Laboratories, where he directs research on systems and network security, cryptography, privacy and risk management, and is responsible for transferring security technology developed in HP Labs to customers and business units.