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.