Patrick Park has been working on product design, network architecture design, testing, and consulting for more than 10 years. Currently, Patrick works for Cisco as a VoIP test engineer focusing on the security and interoperability testing of rich media collaboration gateways. Before Patrick joined Cisco, he worked for Covad Communications (a VoIP service provider) as a VoIP security engineer focusing on the design and deployment of secure network architecture and lawful interception (under the Communications Assistance for Law Enforcement Act [CALEA]) with various tools and solutions. Patrick graduated from Pusan National University in South Korea, where he majored in computer engineering. While attending graduate school, he wrote the book Web Server Programming with PHP. Patrick lives with his wife and children in Los Gatos, California.