# About the Catalyst 4000/4500

The Catalyst 4000 series of switches includes the Catalyst 4003 and Catalyst 4006 chassis. A key component of Cisco AVVID (Architecture for Voice, Video, and Integrated Data), the Catalyst 4000 Series extends control from the backbone to the network edge with intelligent network services, such as scalable performance. The modular architecture, media flexibility, and expandability of the Catalyst 4000 Series enable a longer deployment life in converged networks.

The Catalyst 4500 series of switches includes the Catalyst 4503, Catalyst 4506, and Catalyst 4507R chassis. Also a key component of Cisco AVVID, the Catalyst 4500 Series extends control to Enterprise wiring closets, branch office and Layer 3 distribution points. The Catalyst 4500 Series is also optimized for business services aggregation and subscriber access in the metropolitan area for network operators and service providers.

The supervisor engines supported by these devices are based on Cisco IOS software, enabling the use of a single Cisco IOS configuration and software image for multilayer switching. Key features include:

- nonblocking integrated Layer 2, 3, and 4 performance at a minimum of 48 Mbps

- traditional LAN switching

- multilayer IOS services with IP routing

- advanced Quality of Service (QoS) functionality

- sophisticated traffic management

- comprehensive security

- simple management