POE (Power Over Eithernet)

I have a small school library that I want to put a WIFI signal in. I want to use POE.

Has anyone used any POE devices and can they recomend which ones to use. Im also wondering about having a POE access point rather than a Router, eg why ad another router that will just have to be set up etc. rather than an access point that negotiates with an existing router. (if you can do that with POE)

Any advice ?

thanks.

Reply to
steve
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~ I have a small school library that I want to put a WIFI signal in. I ~ want to use POE. ~ ~ Has anyone used any POE devices and can they recomend which ones to ~ use. Im also wondering about having a POE access point rather than a ~ Router, eg why ad another router that will just have to be set up etc. ~ rather than an access point that negotiates with an existing router. ~ (if you can do that with POE) ~ ~ Any advice ? ~ ~ thanks.

If 802.11g is adequate to your requirements, then a Cisco Catalyst Express

520-8PC switch with Cisco 521 Wireless Express Access Points would likely meet your needs.

Aaron

Reply to
Aaron Leonard

Thanks I will look at those.

Reply to
steve

On Sep 8, 11:48=A0am, Aaron Leonard wrote

Especially if you don't mind spending $1,500 dollars! You are trying to simplify, therefore need to install a $1000 switch to get POE? I think you can buy a POE injector/splitter combo for far less and then just use a consumer grade router.

I don't know squat about POE, but here's once place that has injectors etc.

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Reply to
seaweedsl

Yes well I would like to get the best but I dont have 1500 dollar budget for this. I tried looking for the Cisco unit but sadly I could not find it locally. I asume it is a high end product. It was my mistake however since I didnt quote how much I would like to spend. I would say around 200 dollars. The fact that I didnt get too many responses may mean that few have use these. Frankly when I walk into 5 out of 5 stores so far none have had or even know about poe. They all seem to have power through the wall socket type units. eg it sends the signal through the wall socket. Reverse of POE. These may? be good units I dont know. I wonder if anyone has had any experience on these ??

Regards

Reply to
steve

Steve, I've used both 11mb and 85mb units (based on the HomePlug spec) which bridge over the house wiring... primarily due to the fact that my son-in-law's house has foil covered insulation in most of the floors (wifi was a miserable failure between floors).

These units have worked very well for me, good bandwidth. I have one plugged into the broadband router, one travels with the house desktop wherever it may be at any given time, and one travels with their laptop all around the house, yard, wherever.

Reply to
Froggie the Gremlin

~ Yes well I would like to get the best but I dont have 1500 dollar ~ budget for this. I tried looking for the Cisco unit but sadly I could ~ not find it locally. I asume it is a high end product.

I was kind of afraid you'd say that. Cisco brand products are not cheap. (On the other hand, they do tend to work.)

~ It was my ~ mistake however since I didnt quote how much I would like to spend. I ~ would say around 200 dollars.

A Linksys SRW208P switch is in that ballpark, and provides 15.4W 802.3af PoE on 4 ports (or 7.5W on 8 ports.)

Next question is, what PoE powered APs are you going to use?

A little Googling shows that D-Link seems to have the cheapest 802.3af APs around.

The fact that I didnt get too many ~ responses may mean that few have use these. Frankly when I walk into 5 ~ out of 5 stores so far none have had or even know about poe.

You'll probably have to order online.

Regards,

Aaron

Reply to
Aaron Leonard

Aaron; it seems like you do have experience with POE, so I'm wondering-

why you suggest a switch instead of an injector? In case he has to install more than one AP? similarly, is a splitter not as good as an actual POE powered AP? Or is it just the elegance factor?

Otherwise, I'd think that $50-60 for an injector and splitter combo, and then $60 for a Linksys WRT54GL (DD-WRT) would be a very cheap solution. Oh, I see that Steve prefers less setup, so get a dedicated AP/Client, same cost.

Again, I don't know squat, but how complicated can it be? It's just a matter of breaking out a couple of wires and feeding them DC, right?

Steve: I have an installation with an ethernet client (same thing- could be AP) up on pole in a rootenna box. Instead of POE, I just ran some 16 ga. zip cord spliced it into the power supply cord for the 30 feet I needed to run power. I did not do any voltage loss calcs, but it's for an older Linksys WRT54G which I understand has a wide range voltage tolerance. Works fine, of course.

Yes, I had to zip-tie two cables instead of one to the post, but so what?

I'm sure there are shortcomings to this that aren't evident in my application, but it might work for you as well.

Reply to
seaweedsl

Following a thread on Ubiquity products, I found this new AP/client station which may be just what you are looking for:

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It comes with a power injector included.

Supposedly, this is a quality company that is a notch above consumer grade. It includes a fairly wide angle directional antenna, so this unit could work for you if you could install it high in a corner to cover your library.

Seems like the perfect solution. You could buy two and stay under budget !

Reply to
seaweedsl

I don't have a full solution, mostly because you didn't bother to supply any numbers (how many ap's, how many ports, how much bandwidth, what else gets plugged in, etc). Some clue as to the existing equipment would also be helpful. However, I think I can guess you're using one or two AP's to cover the library. Methinks PoE is a waste of time with such a small system, but if you're installing the AP in the ceiling, it's a very practical way to power the AP. For such small systems, a simple single port injector system works well. I've been using Cisco AIR-PWRINJ1 injectors mostly because I got lucky bidding on 10 of them on eBay. Make sure whatever you buy does

802.3af at the rated power of your proposed access points. Some of the Dlink, Linksys, and other cheap injectors are nothing more than a crude way to supply 5V or 12V DC to the access point over the CAT5 wiring. Look at the power supply with the injector. If it says 48VDC, you have "real" 802.11af. If it's 5V or 12V, it's junk.

There are larger systems called "wireless switch" systems that do what you want, but are made to manage a large number of access points from a central location, such as in a large office building. For example:

Methinks these are overkill, but if your library is huge, they might be a good idea. Also:

Note that all of these will run off PoE from the "concentrator" (at the bottom of the page).

However, if you wanna do this cheaply, you can build your own system. Since you want to preserve the existing router and probably also have an existing ethernet switch, you need is a midspan PoE injector. I've used a Phihong POE125U-560-8:

which worked well for about 3 months until it was stolen last week.

I'm not sure what to recommend for cheap access points. I don't know if you need dual band, SNMP management, external antennas, seamless roaming, MIMO speeds, multiple SSID's, or other features. Just about anything will work with the Phihong PoE injector at 15 watts per port. However, if you go for a higher power consumption device, you may need to purchase one of their higher power units.

Reply to
Jeff Liebermann

~ > A Linksys SRW208P switch is in that ballpark, and provides 15.4W 802.3af ~ > PoE on 4 ports (or 7.5W on 8 ports.) ~ >

~ > Next question is, what PoE powered APs are you going to use? ~ >

~ ~ Aaron; it seems like you do have experience with POE, so I'm ~ wondering- ~ ~ why you suggest a switch instead of an injector? In case he has to ~ install more than one AP?

Exactly so. We have customers who install hundreds of APs in a building, and they certainly don't want to install hundreds of power injectors in their switch rooms and wiring closets.

Another advantage of using a PoE switch is that you can power on/off the AP under software control. For example, this will let you powercycle a recalcitrant AP that is installed in some ceiling somewhere from the comfort of your desk.

~ similarly, is a splitter not as good as an actual POE powered AP? Or ~ is it just the elegance factor?

The power injector can do just as good a job of delivering power to the AP - but in large scale installations, the "elegance" factor is decisive.

Regards,

Aaron

Reply to
Aaron Leonard

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