Clock synchronisation

Synchronisation of clocks is a problem in parallel and distributed systems. In these systems, each node (like a CPU core or networked server) operate with separate physical clocks. Different clocks may have skew and drift:

• Skew is the instantaneous time difference between two clocks.

• Drift is the rate at which clock skew increases between two clocks.

• Time-based clocks

  • Computer clock
  • Atomic clock
  • Cristian’s algorithm

• Event-based clocks

  • Logical clock
  • Vector clock