Network Time Protocol (NTP)

Network Time Protocol (NTP)

We've run into an issue with NTP..figure I'll trace out my notes here:

Network Time Protocol (NTP) is a networking protocol for clock synchronization between computer systems over packet-switched, variable-latency data networks.

NTP uses a hierarchical, semi-layered system of levels of clock sources. Each level of this hierarchy is termed a stratum and is assigned a layer number starting with 0 (zero) at the top. The stratum level defines its distance from the reference clock and exists to prevent cyclical dependencies in the hierarchy. It is important to note that the stratum is not an indication of quality or reliability, it is common to find stratum 3 time sources that are higher quality than other stratum 2 time sources. This definition of stratum is also different from the notion of clock strata used in telecommunication systems.




It should be noted that a router cannot be a stratum 1 device (cannot connect to a Stratum 0 device such as a GPS clock), a router is not an accurate source of time information.  If this is not important, then using a router as an NTP server may be appropriate.