The Cisco MGX PXM-1E Processor Switch Module is a combination ATM switching fabric and ATM interface, and processor card. The PXM-1E provides flexible support of ATM interfaces and allows fast and efficient expansion of ATM modular optics from one OC-3c/STM1 to eight OC-3c/STM3 ports.The Cisco MGX PXM-1E combines a 1.2-Gbps shared-memory switching fabric with integrated trunking at speeds up to 622 Mbps. The switching fabric provides 1.2 Gbps of nonblocking switching capacity, while the processor provides the control plane that delivers advanced multiservice networking software, diagnostics, and performance monitoring.