Catalyst 2900 series XL switch modules are high-performance, field-installable expansion cards that enable users to grow their networks, minimize network downtime, and migrate to new technologies as their needs change. The Catalyst 2900 XL modules support virtual LAN (VLAN) trunking with standards-based 802.1Q and Inter-Switch Link (ISL) protocols, enabling superior functionality for end-to-end network management.Each Catalyst 2912MF XL, Catalyst 2916M XL, and Catalyst 2924M XL switch contains two slots and supports a broad range of expansion modules. The Catalyst 2900 XL switch modules are the ideal solution for workgroups and individual users who need increased performance and expandability at an affordable price. The switch modules provide 10BASE-T/100BASE-TX, 100BASE-FX, 1000BASE-X, 1000BASE-T, and Asynchronous Transfer Mode (ATM) connectivity to servers and network backbones. Catalyst 2900 XL switch modules support dedicated connections to 10BASE-T/100BASE-TX, 100BASE-FX, and Gigabit Ethernet servers. All modules can be configured to provide high-speed, fault-tolerant Fast EtherChannel and Gigabit EtherChannel connections to server farms or power users. Catalyst 2900 XL modules connect Catalyst 2912MF XL, 2916M XL, and 2924M XL switches directly to 100BASE-TX, 100BASE-FX, Gigabit Ethernet, and ATM backbones over UTP or fiber cabling. In these configurations, a Catalyst 2900M XL switch can be connected directly to routers, access servers, switches, and workgroup servers. Any combination of modules can be used in a modular Catalyst 2900M XL switch to meet your network needs. For example, a Catalyst 2916M XL or 2924M XL switch with a four-port 10BASE-T/100BASE-TX module can provide a local 100BASE-TX backbone with low-cost connectivity to other switches and servers. A four-port 100BASE-FX module in the same switch's second high-speed expansion slot provides fault-tolerant, fiber connectivity to the campus backbone. The Catalyst 2912MF XL switch, with the addition of two four-port 100BASE-FX modules, can aggregate a total of 20 separate fiber connections on a campus network. Finally, the Catalyst 2900 XL switches dual-slot design also provides the ideal bridge between Gigabit Ethernet and ATM in mixed networks.