A modular centralized design of WS-X4548-GBRJ45 allows customers to use their investment in high-performance line cards across the entire line of Cisco Catalyst 4500 Series chassis and supervisor engines. For example line cards shipping with the original Cisco Catalyst 4003 Switch will work in the new Cisco Catalyst 4500 Series running the Cisco Catalyst 4500 Series Supervisor Engine V-10GE