Time

Pages on this website

• Lindy Precision Clock driver
  I'm developing a driver for the NTP daemon reference implementation for the Lindy Precision Clock.
• Jans
  Jans is an unusual NTP server: it can return the systemclock time (and just that) but it can also return blatantly incorrect time.
• nmea-ntp-dev-4.2.5p158.diff.gz
  Patch against ntp 4.2.5p158 to enable NMEA-PPS.
• my setup
  My servers are part of the NTP pool project. One can see here what my network consists of.
• ntp - be on time, always
  For the "deb-a-day"-website I wrote an article trying to convince people to become part of the NTP pool.
• NTP monitor
  One can let his/hers NTP server be monitored via this page.
• OmniSync
  OmniSync is a driver for NTPd for people who are firewall-challenged. It allows you to sync against the daytime service (port 13 tcp/udp), time (port 37 tcp/udp), http and https (both also via proxy server).
• Query NTP server
  At this page one can check if their NTP server is reachable over the internet.
• ppsldisc.patch.bz2
  Patch to make ppsldisc (Linux PPS patch) behave like a more UNIX-like daemon (forks itself into the background and writes pid to a file).

Links on the net

devices

• Cesium: also known as atomic clock
  
• DCF77: German time signal
  
• GPS: Global Positioning System, also emits a time signal
  
• HBG: Swiss time signal (uses DCF-77 protocol)
  
• MSF: time signal from NPL (UK)
  
• NTP: Network Time Protocol, a method for distributing the current time across a network
  
• OCXO: a crystal in controlled-temperature environment
  
• PPS: Pulse Per Second
  
• Rubidium: also known as atomic clock
  
• TCXO: a crystal oscillator
  
• TDF: French time signal
  
• VCO: voltage controlled oscillator
  
• WWVB: NIST time signal (US)
  

software

miscellaneous

• Linux PPS
  Rodolfo Giometti is developing a PPS implementation for the Linux kernel.
• atomic-clocks.com
  This company has atomic clock watches/clocks/etc. Only for US!
• how atomic clocks work
  Web-page describing how atomic clocks work.
• radio clocks for pcs
  Building your own radio-clock. Describes hardware for a DCF-77 as well as an MSF receiver.
• RFC868
  Describes the 'time'-protocol which can be retrieved via port 37 (TCP and UDP).
• RFC1305
  Describes the 'network time protocol' (port 123 UDP). This one is preferred over 'time' (port 37) as it also handles delays and jitters correctly.
• Time @ wikipedia
  Document in Wikipedia which describes time.
• PIC NTP server
  A microcontroller based NTP server, synchronized to a GPS receiver.
• IEEE 1588
  A precision clock synchronization protocol for networked measurement and control systems.