In a time-slotted status-update system whose transmitter and receiver keep unsynchronized local clocks, clock drift changes the Age of Information (AoI) -- the time elapsed since the freshest successfully received update. Modeling deterministic and probabilistic slot drift over an unreliable Bernoulli channel, closed-form expressions for the AoI distribution and average AoI follow from the stationary distribution of a two-dimensional discrete-time Markov chain over the joint drift-and-age state. The analysis yields the tolerable drift budget under an average-AoI threshold and motivates a referential (relativistic) notion of information freshness in which timeliness is frame-dependent.
A cs.IT letter analyzing the Age of Information (AoI) in a time-slotted status-update system when the transmitter's and receiver's local clocks are not synchronized. Dropping the usual assumption of …