{"draft":"draft-ietf-ntp-chronos-25","doc_id":"RFC9523","title":"A Secure Selection and Filtering Mechanism for the Network Time Protocol with Khronos","authors":["N. Rozen-Schiff","D. Dolev","T. Mizrahi","M. Schapira"],"format":["HTML","TEXT","PDF","XML"],"page_count":"13","pub_status":"INFORMATIONAL","status":"INFORMATIONAL","source":"Network Time Protocols","abstract":"The Network Time Protocol version 4 (NTPv4), as defined in RFC 5905,\r\nis the mechanism used by NTP clients to synchronize with NTP servers\r\nacross the Internet. This document describes a companion application\r\nto the NTPv4 client, named \"Khronos\", that is used as a \"watchdog\"\r\nalongside NTPv4 and that provides improved security against\r\ntime-shifting attacks. Khronos involves changes to the NTP client's\r\nsystem process only. Since it does not affect the wire protocol, the\r\nKhronos mechanism is applicable to current and future time protocols.","pub_date":"February 2024","keywords":["NTP","NTPv4"],"obsoletes":[],"obsoleted_by":[],"updates":[],"updated_by":[],"see_also":[],"doi":"10.17487\/RFC9523","errata_url":null}