Signal-Based vs. Time-Based Synchronization

Synchronizing multiple devices requires accurate timing for event synchronization and data correlation. NI-Sync achieves timing accuracy between devices using two synchronization methods: signal-based and time-based.

In a signal-based application, clocks and trigger signals are shared directly between nodes that require synchronization. In a time-based application, nodes independently synchronize their individual clocks based on a common time source, usually an external timing reference like GPS.

Note A combination of signal-based and time-based programming is often the best choice for complex system configurations with many different types of nodes in different locations.

Refer to the following table to weigh the pros and cons of using signal-based or time-based synchronization in an application:

Signal-Based Time-Based
  • Nodes are less than 100 meters apart.
  • System has no access to an external time reference.
  • Nodes are physically connected using cables or switches
  • System is in a closed environment without network access.
  • System requires higher precision synchronization.
  • System requires synchronization of a small number of nodes.
  • Nodes are more than 100 meters apart.
  • System has access to an external time reference, such as an IRIG generator or a GPS antenna.
  • Nodes are connected through a network (including through Ethernet).
  • System requires synchronization of a large number of nodes.
  • Nodes frequently change location.