Session ID (or actor ID, site ID, process ID, etc.), a random identifier randomly assigned to each editing session.
Logical time (or sequence number, tick, etc.), a monotonically increasing integer, starting from 0. It does not produce gaps on local machine, but it can produce gaps when merged with other clocks.
Needs to be mutable in vector clock. Other than that, it should be treated as immutable.
Represents a logical clock timestamp. Logical timestamps are used to identify all JSON CRDT operations, objects, and parts of their contents, e.g. timestamps serve as unique IDs.