D-Link DES-1316K review

Although the 802.af PoE (Power over Ethernet) specification was ratified back in 2003, it’s taken a few Ethernet switch vendors an inordinate amount of time to deliver compliant products. The leading vendors, including HP and 3Com, announced a range of switches at the beginning of 2004, but only now is D-Link dipping its toes in the same water.

The DES-1316K is an interesting variation on the power theme, as it allows pretty much any device to be powered from the PoE ports. You can connect compliant products directly to its Ethernet ports, but the additional DWL-P50 adaptors split the Ethernet and power feeds from the switch. The power feed is converted to either 5V or 12V, which can be supplied directly to the device via the supplied female-to-female power connector. A small switch on the unit allows you to manually select the correct output voltage, but note that the adaptor may not work with many products, as the power cable connectors are of the larger 5mm variety. We attempted to connect a non-PoE Axis 211 Network Camera, but its power socket was smaller than the adaptor plug.

The dull brown chassis and fascia make the DES-1316K uninteresting to the eye, but underneath its bland exterior lies a reasonable hardware specification. The 16 dual-speed Ethernet ports are arranged in two groups, as only the left-hand set of eight ports is capable of providing power. The switch is an end-span device. This means the ports provide power over the same wire pairs used for data delivery, so end devices can be powered directly from the switch. However, being fully 802.3af-compliant, they contain automatic detection circuits that prevent them from sending power to non-compliant terminal devices. So only those that present an authenticated PoE signature will receive power. Status information is reasonable, as a bank of LEDs provides visual cues to link status, speed and activity. A separate LED for the PoE ports shows which are providing power or have suffered a power failure.

The switch doesn’t offer a serial port or CLI access, although first contact is simplified with the bundled utility that searches the network for D-Link switches and displays them ready for configuration. You can go directly to web-browser access from here, but the utility can also maintain a log of SNMP traps from the switch and provide direct access for firmware upgrades. The browser interface is a tidy affair and opens with an overview of switch, port and VLAN status. It isn’t as slick as that provided with HP’s switches, but it does provide a reasonable level of detailed information and easy access to the switch settings. The DES-1316K offers a standard diet of Ethernet-related features with support for 802.1q VLANs and 802.1p packet prioritisation, while port mirroring allows you to send data from one port to another with a network analyser attached. Up to four ports can be joined together in a trunk for a high-speed link to a server or another switch, but note this feature is supported only on the non-PoE ports.

For PoE testing, we used an Axis 211 Network Camera and a 3Com Series 8000 access point, and both worked fine. However, PoE controls are at an absolute minimum, as all you can do is enable or disable this function on the appropriate ports. The port status screen shows supplied power in watts, voltage and MW, but there’s nothing else you can do. Unlike switches such as 3Com’s 2226-PWR Plus, there are no options to prioritise power to specific ports when the load reaches the maximum supported, and power limits can’t be applied to each port either.