What Users Should Know About ATM Carrier Services

摘要

Who needs asynchronous transfer mode (ATM) service? For the most part, it is expensive, requires customer premises equipment (CPE) with a user-to-network interface (UNI), is currently limited to permanent virtual circuits (PVCs), and offers little in the way of added capabilities. Although ATM service has been available from a few carriers since 1993, there has been no rush by users to grab the bandwidth. The carriers refuse to disclose the number of customers, perhaps because they are embarrassingly low. ATM services are expensive and most carriers do not provide access links below T3 and then jump from there to OC-3. The bandwidth of the access links limits the number of ATM users to those who can already justify leased T3 lines. Also, there is currently no intercarrier linkage, which eliminates ATM communication between users connected to different carriers. Just imagine if your local telephone company could not connect you with a person because that person happens to subscribe to a different carrier.