Asynchronous transfer mode (ATM) has been suggested as a flexible and efficient transmission standard for future broadband ISDN (B-ISDN). Admission control determines whether to accept or deny a new connection request based on traffic characteristics of the new call, its quality of service (QOS) requirements, and current network status. In most of previous work, the long-term time-averaged cell loss probability and/or the cell transmission delay are adopted as the criteria of admission control. Using the long-term time-averaged values may not be appropriate in ATM networks because the traffic can change rapidly and dynamically. In this paper, we propose to use a minimum mean square error estimator of the instantaneous cell loss rate as an additional criterion for admission control and study the dynamic behavior of an ATM switch with burst-silence inputs.