Cisco LAN switch IP telephony

Cisco Systems Inc. is rolling out a LAN switch for mid-sized companies that is to be deployed in IP telephony networks. The Catalyst 3524-PWR XL features 24 Fast Ethernet ports and two Gigabit Interface Connector (GBIC) ports. The switch features inline power and quality-of-service enhancements specifically designed for IP telephony. With integrated inline power, the Catalyst 3524-PWR XL detects the type of IP device on each port, such as an IP phone, and powers it using 48-volt DC power over Category-5 unshielded twisted pair cable. With inline power, an uninterruptible power supply (UPS) or separate wall power is not required for each IP phone, Cisco says. Cisco recommends deployment of redundant power supplies to backup switch power, however. For QoS, the Catalyst 3524-PWR XL supports port-based reclassification, allowing users to change IEEE 802.1p class-of-service settings on a per-port basis. This enables users to prioritize voice traffic ahead of file transfers or Web surfing, Cisco says. For reliability, the switch utilizes Layer 2 functions such as virtual LANs, fast convergent Spanning Tree, and other features to enhance network stability. For security, the switch prevents intrusion by limiting port access to specific MAC addresses. Also, TACACS+ is used to authenticate management access to the switches. And the 3524-PWR XL includes a feature called “Private VLAN Edge,” which provides isolation between ports on a switch so that traffic from “protected” ports is only sent to the uplinks and cannot travel to another port within a switch. The Cisco Catalyst 3524-PWR XL is available today and has a list price of US$3,995. Cisco can be reached at

Prices listed are in US currency.