A Security Analysis of Version 2 of the Network Time Protocol NTP: A Report to the Privacy and Security Research Group Dartmouth Technical Report PCS-TR91-154 Matt Bishop Date: 1991 URL (PDF): (1004KB) Abstract: The Network Time Protocol is being used throughout the Internet to provide an accurate time service. This paper examines the security requirements of such a service, analyzes version 2 of the NTP protocol to determine how well it meets these requirements, and suggests improvements where appropriate.