Power over Ethernet (PoE) is one of those technologies that you don't really appreciate until you start to use it. Then it quickly becomes indispensable, especially if you happen to work for a large firm and need to deploy hundreds, if not thousands, of electronic devices.

To start with it does away with all those unsightly "wall warts", aka AC adapters, while at the same time allowing far simpler deployment of all kinds of network hardware.

No longer do you have to hunt down an outlet for every bit of kit or run in additional cables to power each new webcam, IP phone or wireless access point. Instead, power is simply pumped out over the same wires used to carry data and, as soon as it's attached, the hardware is ready to use.

Of course there are limits, with an absolute ceiling of just 13 watts per port, set by the 802.3af PoE standard. Moreover, in practice, that's rarely achieved, so all kinds of device you'd like to be able to power via your LAN can't be powered this way. At least not at present, although there are moves afoot to increase the current limit (no pun intended). A new IEEE study group was established last month to extend the 802.3af spec.

The leading light behind the move is PoE pioneer PowerDsine, which, as a major vendor of the supporting technology, clearly has a vested interest in extending the standard. However, the new study group was voted in by some 22 IEEE members, indicating a lot of interest among networking firms in general.

The purpose of the new group is to come up with a new standard, backwards compatible with existing 802.3af technology, to let devices draw a lot more than 13 watts.

Dubbed PoEplus, the new system should enable things like PDAs, notebooks, and even desktop PCs to draw current from the LAN. How much power exactly is a major talking point but some group members suggest 40 watts or more. However, that won't be easy as twisted pair cabling was never intended to carry large power loads and there are issues of interference and safety to resolve.

One of the biggest concerns has to be heat build up. And it's important to be able to deliver the right amount of power to different devices plugged into the same LAN. Important, for example, to make sure power-hungry devices get just what they need while making sure that those able to exist on a lighter diet aren't inadvertently fried.

Still, given the rapid growth of wireless and voice over IP technologies together with a seemingly insatiable appetite for mobile devices in general it can't be long before such problems are resolved and a standard for PoEplus is agreed.

At the same time, however, its worth noting a parallel resurgence of interest in the use of power lines to carry data, and in particular to deliver consumer broadband connectivity. So much so that I'm starting to wonder if we're not at the dawn of a new era of convergence, the result of which might be calls for a single combined power and data infrastructure any day now.