1. Embedded System on NTP 2009 Fourth International Conference on Computer Sciences and Convergence Information Technology Chien-Chi Chao Shih-Ping Huang Ho-Lung Hung 1

2. Outline Introduction – Network Time Protocol (NTP) – NTP Pool Project Experiment Conclusion Reference 2

3. Introduction The Network Time Protocol (NTP) (RFC 1305) is proposed in 1980. Original NTP Topology 3

4. Introduction cont. Clock synchronization flow chart with NTP. 4

5. Introduction cont. The NTP Pool Project, a self-voluntary organization, is founded by Adrian von Bidder. The main goal of the NTP Pool Project is to provide the free service of the time synchronization. The union of the assistances from the different sources equips the NTP Pool Project to become a successful project. 5

6. Introduction cont. The NTP Pool Project Topology. 6

7. Experiment 7

8. Experiment cont. The operational process of the NTPD 8

9. Experiment cont. 9

10. Conclusion The NTP Pool Project is a well-designed network system based on the distributed framework to avoid the network traffic. After installation of the NTP software, we need to check the NTP setting to avoid the selection of the NTP server too far away. 10

11. Reference David L. Mills, “Internet Time Synchronization: The Network Time Protocol,” IEEE Transactions on Communications, Vol. 39, No. 10, Oct 1991. NTP Pool Project, http://www.pool.ntp.orghttp://www.pool.ntp.org RFC 1305 11