This integer sets, in seconds starting from a minimum of 60, how often the device performs a user-sync operation to reconcile its local subscriber session state with an external system such as an authentication or accounting server. An admin tunes this interval to balance how quickly session state drifts get corrected against the load the sync process places on the device and the remote server. For example, leaving this at its 60-second minimum keeps subscriber state tightly synchronized at the cost of more frequent sync traffic.