1. Efficient Reliability for NRC Time Services

2. NCSLI 2008 2

3. 3 Canada’s Official time available to all.

4. NCSLI 2008 4 CBC “…The beginning of the long dash…” Talking clock Web clock Radio station CHU Computer modem service Network Time Protocol (NTP) NRC TIME SERVICES

5. NCSLI 2008 5 NRC time services statistics for 2007 Talking Clock 616,857 Web Clock 568,651 Computer Code 32,211 Network Time Protocol 7,124,679,958 Calls per year Hits per year Calls per year Hits per year

6. NCSLI 2008 6 NRC Time Dissemination Equipment

7. NCSLI 2008 7 Time Dissemination equipment

8. NCSLI 2008 8 Network Time Protocol (NTP) Hierarchy Clock Stratum 1 Server Reference Clock Stratum 1 Server Reference Clock Stratum 1 Server Reference Stratum 2 Server Stratum 2 Server Stratum 0 Stratum 1 Stratum 2 Network path Serial stream Atomic clock

9. NCSLI 2008 9 A stratum-1 server at NRC Atomic clock UTC(NRC) 1pps Leitch Clock Stratum 1 Time server tic.nrc.ca Stratum 1 Time server tac.nrc.ca Stratum 1 Time server toc.nrc.ca

10. NCSLI 2008 10

11. NCSLI 2008 11 Radio Station CHU Time Dissemination Equipment

12. NCSLI 2008 12

13. NCSLI 2008 13 Typical Internet Node Radio Propagation DelayTelephone Line Delay

14. NCSLI 2008 14 English - http://inms-ienm.nrc-cnrc.gc.ca/time_services/time_services_e.html French - http://inms-ienm.nrc-cnrc.gc.ca/time_services/time_services_f.html NRC time services web site

15. NCSLI 2008 15 THE END

16. NCSLI 2008 16 Leap Second History

17. NCSLI 2008 17 Year overflow 1900-01-01 2036-02-07 1968-01-20 2036-02-072172-04-03 1901-12-13 1970-01-01 2038-01-19 NTP overflow UNIX/Linux overflow 2007 32 bit timestamp NTP ver 3 NTP ver 4

18. NCSLI 2008 18 Time server rack Web server time5.nrc.ca Stratum 1 time server tac.nrc.ca Stratum 1 time server toc.nrc.ca Stratum 1 time server tic.nrc.ca Leitch serial interface KVM switch Stratum 2 time server time.inms.nrc.ca Stratum 2 time server time2.inms.nrc.ca UPS 1 UPS 2 Keyboard, monitor, mouse

19. NCSLI 2008 19 CHU code in Star Wars