NTP users are strongly urged to take immediate action to ensure that their NTP daemons are not susceptible to being used in distributed denial-of-service (DDoS) attacks. Please also take this opportunity to defeat denial-of-service attacks by implementing Ingress and Egress filtering through BCP38.
ntp-4.2.8p15 was released on 23 June 2020. It addresses 1 medium-severity security issue in ntpd, and provides 13 non-security bugfixes over 4.2.8p13.
Are you using Autokey in production? If so, please contact Harlan - he's got some questions for you.
Clock Models (Boris) (GSoC 2011)
The goal of this project is to study the different clock models used in NTP, understand the basicas and operation of the NTP itself and propose and improved NTP clock algorithm.
In my project, I will make a research to understand what already exists in the NTP clock algorithms. I will then test this algorithms using the NTP build-in simulator and evaluate their performance. I will also try to propose the new improved algorithm using both mathematical/statistical models and NTP - build-in simulator. Furthermore, I will study the parameter which gives us a explicit connection between polling interval and accuracy of the synchronization process. At this moment, I am writing a progress reports about the basic concepts of the NTP.
Related Items: ClockAlgorithms
First Progress report
First progress report contains the information about the Frequency-Locked Loops and describes their detailed operation. It also decribes the mechanism how the FLL locks to the reference frequency.
Second Progress report
Second progress report contains the information about the Phase-Locked Loops and describes their detailed operation. This includes the mechanism which allows the PLL to lock to the particular phase.
Third Progress report
Third progress report contains the detailed differences between the PLLs and FLLs. Moreover it describes their example of usage.
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