Cisco 5505 Installation Guide - Page 3

Chapter 4 Installing the ASA 5505 PoE Ports and Devices PoE Ports and Devices On the Cisco ASA 5505, switch ports Ethernet 0/6 and Ethernet 0/7 support PoE devices that are compliant with the IEEE 802.3af standard, such as IP phones and wireless access points. If you install a non-PoE device or do not connect to these switch ports, the adaptive security appliance does not supply power to the ports and the device must be powered on its own. These ports are the only ports that can provide power for IP phones or other PoE devices. However, these ports are not restricted to that use. They can also be used as Ethernet switch ports, like the Ethernet switch ports numbered 0 through 5. If a PoE device is not attached, power is not supplied to the port. When connecting PoE devices, use the following guidelines: • Use straight-through cable only. Using crossover cable does not enable the Cisco ASA 5505 to provide power to the PoE ports. • Do not disable auto-negotiation (force speed and duplex) on E0/6 and E0/7 when using them to connect PoE devices. If auto-negotiation is disabled, the Cisco ASA 5505 does not recognize that a PoE device is attached. In this case, power is not provided to the port. Note Be careful when connecting a Cisco PoE device to a non-PoE switch port (E0/0 through E0/5). If auto-negotiation is disabled for that switch port, a network loopback might occur with some Cisco Powered Device (PD) models. • The Cisco IP Phone 7970 is always in low-power mode when drawing power from the Cisco ASA 5505. 78-18003-02 ASA 5505 Getting Started Guide 4-3