Affordable switches with Power over Ethernet (PoE) capabilities have been around for a while now, enabling small businesses to deploy wireless access points, network cameras and IP phones without the need for AC adapters and dedicated mains sockets. However, the new 16-port ProSAFE GS516TP PoE Smart Switch from Netgear (around £220 ex. VAT) breaks new ground in that, as well as delivering power via the network, the switch can be plugged into a PoE source and powered over the LAN.
Look, No [AC] Wires!
Designed to be used by small to medium sized businesses with up to 500 users, the first thing you notice about the ProSAFE GS516TP is its lack of size, with 16 Gigabit ports neatly packed in a compact and surprisingly smart looking metal case.
Brackets for rack mounting are included or it can be desk mounted, although it is fan-cooled and makes a fair amount of noise even when not doing much. For a network switch it’s not particularly noisy, but we certainly wouldn’t want to sit next to it and would recommend putting it in a comms cupboard or server room.
There’s a built-in power supply should you want it but as a PoE Powered Device (PD) the ProSAFE GS516TP can also get its energy over the LAN from another PoE switch or mid-span device. That makes for much simpler installation in cupboards, ceiling voids and other locations not supplied with AC mains outlets. All you have to do is run a data cable to it (Cat 5 or above), making installation a relatively simple affair.
Two of the 16 ports located on the front of the switch are capable of handling power delivered this way – ports 15 and 16, clearly marked in yellow and with their port numbers highlighted in orange to avoid confusion.
No special setup is required to get it working. We simply plugged leads from PoE ports on another switch into the PD ports on the Netgear and it sprang into action, powering up in just a few seconds and lighting the appropriate LED to indicate where the power was coming from.
The only requirement is for a 30 Watt PoE+ (802.at) connection to enable the switch to boot from just one wire. Users with only a standard 15.4 Watt (802.3af) PoE source will have to run two cables to get it working (to both port 15 and 16) – use one and it just hangs mid-boot with all the lights on but nobody at home.
We Have The Power
On the output side ports 1-8 can all deliver power to PoE enabled devices and are, again, clearly marked so you know which ones to use. These ports are limited to providing just 15.4 Watts (802.3af) each but that’s more than enough for the kind of end-point devices most small businesses want to deploy – mostly access points and IP phones. There is, however, a ceiling on how much power the switch can deliver altogether – referred to as the PoE budget.
When wired into the mains that PoE budget is 76 Watts shared across all eight PoE ports. However, when the switch is driven by PoE it falls to just 22 Watts which, in theory, means only one port can deliver up to the full 15.4 Watts.
Of course just how many devices the PoE budget translates to will depend on what you attach and just how greedy those devices are. For example, for our review Netgear supplied a ProSAFE WN203, a business-class wireless access point (around £60 ex. VAT) which only needs to draw up to 4 Watts on order to connect 802.11n Wi-Fi devices to the network, and most of the time gets by on just 2 Watts.
This worked without any problems when connected to the ProSAFE GS516TP and we could have powered five altogether, even with the switch drawing power over its PD ports. Other products, though, may need a lot more than this to work properly, so some care is needed in choosing what to buy to plug into the Netgear switch.
One line of approach would be to just keep attaching devices to the switch until they stop getting power but, that could lead to trouble. The more prudent, therefore, will want log into the switch and, use the built-in Web console to set the amount of power each port is allowed – to better share out the available budget.
No particular expertise is required and although a little on the slow side the user interface does the job and isn’t hard to pick up, plus you can disable ports altogether if needed or turn the power to a port on and off according to user-defined schedules, for example, to reduce power consumption out of business hours.
And It’s Smart Too
In addition to power management the management interface also lets you configure a number of Layer 2 features built into the Netgear Smart Switch. These aren’t required for basic connectivity – just plug everything in and it will all work straight away – but they do enable the more technically minded to exploit their networks more effectively.
In common with other ProSAFE models that means being able to define up to 256 VLAN to logically separate traffic on the network, with auto voice and video VLAN setups already configured as standard – for use with VoIP phones and IP cameras. Likewise, there are QoS controls to prioritise traffic flows and security tools to limit network access at the port level.
It Has The Power
Whether teamed with Netgear ProSAFE wireless access points or PoE-enabled products from other vendors, the ProSAFE GS516TP is an affordable solution bringing AC-free PD capabilities to the small business market for the first time. There are a few limitations in terms of PoE budget, particularly when powered over the LAN, but nothing too serious. And if you can live with those, it has a lot to offer and is well worth considering. [4/5]