Power over Ethernet

If all you want to do is provide a location where you can put a remote access point, your best bet is to plug the remote access point into a hub or switch nearby.

If you have to setup an access point where there is no existing power but to which you can run an Ethernet line, you can accomplish this by employing what is called a Power over Ethernet or PoE solution.

An access point on a roof would be an example of this application. PoE is an IEEE standard that is hoped will remove the need to have power lines near every wireless device.

It uses unused wires in your Ethernet cabling to carry the DC current. The reason to use PoE is so that you can place an access point next to its antenna. The longer the connection between the two, the weaker both the transmission and reception will be.

A run of more than 3 feet of coaxial cable is enough to fatally degrade an access point’s performance. What PoE does is to use a device called an injector, which supplies the power to the right CAT5 wires, and a tap or splitter that has a power outlet attached to it where your access point’s power adapter plugs into.

An Ethernet signal flows through both of these devices transparently. The technology further provides both passive and active injectors and taps. The difference is that an active device offers some short-circuit, overcurrent, and voltage regulation protection.

You’ll find that injectors use five to ten times the voltage of your access point to maintain a strong signal down the wire. An active tap will have a voltage regulator in it that will adjust the voltage down to 5V DC, which is what many access points use.

With PoE technology, pay special attention to the connection from these devices to your wireless equipment. Some of the plugs are proprietary and incompatible with one another.

PoE not only can cut down on costs, but it can also lower your power bills and help you control your devices. Using the management software for PoE devices you can program when these devices are active. If you have these devices shut off when people are not around, after hours or at night you can lessen the chances of a security intrusion.

When possible, buy PoE kits from the same manufacturer as your access points. For example, D-Link has a PoE adapter, the DHP100 that retails for $95. You’ll find a Web site devoted to PoE at: www.poweroverethernet.com.

Powerline Ethernet

Of course, the reason we call it a “remote access point” is that there is likely not going to be a hub or access point available, and it is difficult if not impossible to run Ethernet cabling to that location.

One way of circumventing the problem is to add a HomePlug Powerline Ethernet bridge to each end of the connection you need to make. Powerline plug adapters plug into your network’s router or switch and also into a nearby standard electrical socket.

The signal runs over your existing house power circuitry and communicates with a plug adapter on the remote end that is attached to your remote wireless access point. Powerline technology is a standard supported by the HomePlug Powerline Alliance which certifies compliance to this standard.

Linksys has the PLUSB10 adapter that uses USB networking over power lines. You need two of each of these devices to make a Powerline connection.

Linksys also has a bridge for Powerline, the Linksys Instant PowerLine EtherFast 10/100 Bridge which can connect the Ethernet port on a router, cable, or DSL modem to a power line connection.

Finally, you’ll find that Netgear XE102 Powerline adapter is another choice. The technology is easy to install and often requires no drivers, but it is pricey and has a slow data transfer rate inappropriate for many applications such as video streaming.

Powerline can transfer data at about 14 Mbps, which is a little faster than 802.11b. This technology isn’t really fast enough to exploit 802.11a, g, and other wireless standards fully and the parts tend to be expensive.

However, there’s no arguing with how convenient this solution is. For access to e-mail, simply browsing the Web, or streaming music to a remote location, Powerline would be sufficient.