The4thWorkshoponInformationSecurityApplications(WISA2003)wassp- sored by the following Korean organizations and government bodies: the Korea Institute of Information Security and Cryptology (KIISC), the Electronics and TelecommunicationsResearchInstitute(ETRI), andtheMinistryofInformation and Communication (MIC). The workshop was held in Jeju Island, Korea - ring August 25-27, 2003. This international workshop provided ample technical sessions covering a large spectrum of information security applications. Subjects covered included network/mobile security, electronic commerce security,...