School deployment access point?

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I'm in a project for a school, the size area is small, 120x150M.

We want to give wifi access tu students but control them by a web-proxy which I will setup, but I'm searching for a AP device with power to support at least 100 users at the same time.

The area doesn't have any wall or building or material that could affect the signal.
is what I see.

I don't want to buy them from bestbuy/waltmart those are not for this.

Some one from point to me this products, them here I'm.

I don't want to have calls telling me that:
--I get disconnected
--Won't let me access.

I have seen other products but they don't fit why:

a) They need OS management/cloud.
b) They are for wide area +1Km.

Don't need them, the first one won't let me manage like a normal AP where u connect your laptop setup the device and plug into the LAN.

The second, the signal goes a way to far.

Does aerohive have some that could fit my deployment?

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  • happy

Posted 5 years ago

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Crowdie, Champ

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When you are designing a wireless deployment there are some factors you need to take into account:

* How many users will be concurrently associated and where?

* What type of wireless clients (laptops, desktops, iPads, iPhones, Android, etc.) will be associating to the wireless network?

* Which applications/services will be utilised across the wireless network? We are particularly interested in their required throughput.

Each access point takes traffic from the wireless client (on either the 2.4 or 5 GHz radio) and places it on the LAN (via an Ethernet interface). Therefore there are several "bottlenecks" and issues you need to deal with:

1. The 2.4/5 GHz radios have maximum speeds and are shared between all the wireless clients associated to the radio. The speeds quoted for radios are raw and to calculate the TCP speed commonly quoted for switches/routers/etc multiply the raw speed by 0.45. So a 5 GHz three spatial stream radio, which has a raw speed of 450 Mbps, has a TCP speed of just over 200 Mbps TCP. If 50 wireless clients were associated to this radio with an even medium access distribution then each client would get 4 Mbps TCP. This, of course, assumes that the wireless clients are almost next to the access point and are able to get the maximum association speed. In real life this is not going to happen.

2. When a wireless clients is transmitting on one channel all other wireless clients on the same channel that can detect the original transmission must wait until the transmission completes before attempting to gain access to the medium again. When a wireless client transmits the 802.11 frame's Duration/ID field is marked with the length of time in ms that the transmission will take to complete. All other wireless clients wanting to transmit listen for other transmissions and set their network allocation vector to the value from the 802.11 frame's Duration/ID field. The wireless clients wait that period of time before attempting to access the medium again.

If you had a single access point servicing 100 wireless clients then it could be possible that 99 wireless clients were waiting for medium access. In the 2.4 GHz spectrum there are three non-overlapping channels so you could utilise three access points (one configured for channel one, another for channel six and the last for channel eleven) and reduce the maximum posssible waiting wireless clients from 99 to 32. If you kept adding additional access points ensuring that no access point configured for channel x had coverage overlap with any other access point configured for channel x you could keep reducing the maximum possible waiting wireless clients.

The 5 GHz spectrum has more than three non-overlapping channels (the exact number is dependent on the country's radio regulations) so the previously described process is even easier in the 5 GHz spectrum.

3. The wireless network must comply with any local radio regulatory requirements. For example, in my country you commonly cannot set the 5 GHz radio transmit power higher than 17 dBm as, with the antenna's passive gain, the total tranmission power, called effective isotropic radiated power (EIRP), would violate my country's radio regulations. This reduces the maximum possible 5 GHz coverage area of any access point. When you configure your country code on the access points it advises the access point which channels can be utilised and the EIRP requirements for each channel (as they can commonly be different in the 5 GHz spectrum).

4. Most enterprise access points have a single Gigabit Ethernet port and all wireless traffic is placed onto the LAN through this single Ethernet port. If you had 100 wireless clients associated to a single access point the single Ethernet port would have to handle all 100 wireless client's traffic bound for the LAN. By utlising more access points (as described in point 2 above) you can spread the load across multiple Ethernet ports.

Therefore, you are better to utilise more smaller capacity access points, like the AP121, than less higher capacity access points, like the AP330, and you will find that this is a commonly utilised design for educational wireless deployments.

The Aerohive access points are managed by an on-premise or cloud based HiveManager NMS. The Aerohive control plane is between the access points so does not require any cloud access.