NTP (Network Time Protocol) is a packet network based synchronization protocol for synchronizing a client clock to a network master clock (see also Configuring NTP.)
Anycast is a network routing protocol in which messages are routed to one of a group of potential receivers via a single Anycast address, thus avoiding the need to configure every client individually.
NTP over Anycast, as implemented in SecureSync, is a combination of the two concepts, allowing SecureSync to:
- Associate one of its network ports to an Anycast IP address, and
- Remove itself as an available time source if its reference is lost or degraded, and vice versa.
To learn more about NTP over Anycast, see also the respective Spectracom Technology Brief (PDF).
Please note that SecureSync utilizes the OSPF (Open Shortest Path First) and BGP (Border Gateway Protocol).
OSPF Protocol EXAMPLE:
If an active SecureSync NTP server has removed itself as an available time source from the Anycast-capable network, the OSPF router will send a request for replacement to the next nearest NTP server, serving under the same NTP over Anycast address.
As soon as the first SecureSync server obtains a valid reference again, it will make itself available to the OSPF router, which will then use it as a time source again, based on the principle of shortest path available.
All NTP Servers are synchronized
NTP Server 1 is out of sync