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Question: Do these only work in pairs? For instance, to connect 3 buildings to the main office, I'd need 3 for the main office and 1 for each of the 3 remotes.
Document: The WiFi access points are directional but with a wide spread/view - almost 180 degrees horizontal with some limited signal distance on the backside of the units - about 50 feet in our case. The WiFi access point signal is useable after passing through several walls (3 drywall + 1 concrete block). In Bridge mode, the signal passes through a chain-link fence with no problem.
After several frustrating months with a competing product (A. Wless' Access Point and Smart Repeater), I purchased two of these to bring Internet to a remote cabin about 3000 feet from a house with broadband Internet. The units cost less than the competition and have worked flawlessly for a week now. There have been no annoying drops or the need to reset the units. My application spans about 3000 feet that has a few overhanging branches, crossing a main road and a railroad line.
I bought a pair of these and set them up to share internet from a friends house 1/2 mile away in line of sight. I can get 40 mbs of internet across there! Very easy to set up, actually aimed them in the dark and never adjusted them. Plugged them in, tweaked a few settings and have been working perfectly since. Not only that, but if you need tech support you can actually talk to someone who speaks English! Great company.
They work great in pairs with line of sight. Not great at penetrating walls. Use one as AP and the other in bridge mode with DLink DAP-2553. Speed is excellent and has worked flawlessly for the past 2 months.
Range is ok the way they said it will go about 1KM. but its work great from close range I do have 3 of them and works great.
This device is supposed to connect offices or remote billboards over 1 km point-to-point connection, but it does several different things:Access Point connected to Router/NetClient Bridge remote (IP Based)WDS Access PointWDS Bridge Mode MAC Based NetworkThe device ships with a 1 page setup page that gives some documentation clues, but most of the documentation is on a mini-CD that requires an old-fashioned spindle drive.
One unit is set up as an "Access Point". This is your "base" unit.3. The other unit is set up as a "Client Bridge". This is your "remote" unit. (We plugged this into an 8 port Switch at the remote location, into which we connected some Allworx VoIP phones, desktop PCs and several local wireless access points. The Allworx VoIP phones work well through this bridge. However, the Allworx control box setup was done by professional techs.
Good Durable Product. Depending on you IT skill level, easy or not so to install.We have installed several pairs of the Engenius ENH202 units for use as wireless bridges and several units as WiFi access points. In the bridge mode, these inexpensive units are communicating well over a 1/2 mile distance, supporting several remote Allworx VoIP phones, a hardwired local network and several separate remote WiFi wireless access points. The units are outdoor, mounted on rooftop posts, utilizing the internal antennas.
I have this for about 9 month or so, the reason for this was to boost RANGE from one end of the house to the other house directly next to each other with about 50 feet air space. The range is spotty from time to time. It claims range of up to 1 mile without obstacle. It won't work in the real world. It does a decent job when signal is strong. We're not sure why the signal drops from time to time.
I've read a lower RSSI is better and anything under -65 is considered a strong signal. The LAN gets about 70mbps, so I expected these to get at least that much speed or very close to it. I have tried reading the forums and used every setting available but that was the best speed I could get.Bottom line: These are great and they are very stable. If you can deal with your wireless speeds being about 1/3rd the speed of your LAN, they work perfect.
Answer: No, you can have multiple units.  Assuming that the main network source is in the main office, you would need to set the one at the main office up as an access point and the 3 remotes as a bridge.  The remotes must have line-of-site access to the main office and the main office unit would need to be pointed in the direction of the remotes.  If the main unit is not pointed in the direction of all remotes, then another unit may have to be installed as an access point at the main office and pointed to connect to those remotes not covered by the first one.