The LightStream 1010 Multiservice ATM Switch uses a five-slot, modular chassis featuring support up to eight hot-swappable port adapter modules (PAMs).The T1 and E1 ATM PAMs are ideal for intercampus, metropolitan, or wide-area links. Each of the ports on this PAM can be configured to support the following clock options: self timing based on ATM Switch Processor clock; loop timing from the received data stream - ideal for public network connections; time synchronized to a selected master clock port, required to distribute a single clock across a network.