The Cisco Catalyst 6500 and 6000 Series provide scalability in performance and services to meet the needs of today's fast-growing enterprise and service-provider networks. Cisco Catalyst 6500 10 Gigabit Ethernet modules further extend this scalability by increasing the per port bandwidth of the Catalyst 6500 by an order of magnitude.The Catalyst 6500 10GBASE-EX4 Metro 10 Gigabit Ethernet module supports an extended reach of 10 to 50 km over single-mode fiber. The module uses 1550nm WWDM technology so customers can use a 5dB 1550nm fixed loss attenuator with the module to achieve distances from 0 to 10 km. The Metro 10 Gigabit Ethernet module supplies one port of 10 Gigabit Ethernet per module via an SC connector. This module comes with the optical interface module (OIM) attached, and the attached OIM cannot be removed or changed to another OIM. Each 10 Gigabit Ethernet module occupies 1 slot and there is no limitation in the number of modules supported per chassis, resulting in up to 12 ports of 10 Gigabit Ethernet in a 13-slot chassis.