The Cisco Catalyst 4000 Series of modular switches include the Cisco Catalyst 4003 and Catalyst 4006 chassis. As a key component of Cisco AVVID (Architecture for Voice, Video, and Integrated Data), the Cisco Catalyst 4000 Series extends control from the backbone to the network edge with intelligent network services including advanced quality of service (QoS), scalable performance, comprehensive security, and simple manageability. The modular architecture, media flexibility, and expandability of the Cisco Catalyst 4000 Series enable a longer deployment life in converged networks. A longer deployment life reduces the overall cost of ownership by minimizing recurring operational expenses and also improves return on investment (ROI). Cisco Catalyst 4000 Series switches are also ideal for business services aggregation and subscriber access in metropolitan-area networks (MANs) that use optical Ethernet in the First Mile.