Real-time based strong consistency for distributed objects

Ordering and time are two different aspects of consistency of shared objects in a distributed system. One avoids conflicts between operations, the other addresses how quickly the effects of an operation are perceived by the rest of the system. Consistency models such as sequential consistency [26] and causal consistency [3] do not consider the particular time at which an operation is executed to establish a valid order among all the operations of a computation. A timed consistency model addresses how quickly the effects of an operation are perceived by the rest of the system, by requiring that if a write operation is executed at time t, it must be visible to the entire distributed system by time t + Δ. Timed consistency generalizes several existing consistency criteria and it is well suited for interactive and collaborative applications, where the action of one user must be seen by others in a timely fashion.