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I have an auditorium measuring 50'x50' and seats 200. I have tried various single consumer router solutions (Asus RT-N12HP, Asus RT-N14UHP, etc) all with disappointing results. I have a good 10Mbps Internet link on fiber, so I don't think Internet access itself is a problem.

As accessing the router's configuration web server is also jittery (when the hall is crowded), I suspect the router may be the bottleneck. The Asus RT-N14UHP says it is capable of 300,000 sessions, whatever that means.

As it is all wireless, I have difficulty figuring out who or what may be causing the problem. Are there some faulty devices jamming up the network for example?

What do people typically do for a scenario like this?

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    Many dozen users can easily overload a consumer-grade router. If there's an AP mode your should try that first, offloading routing and NAT to the upstream hardware. If not, try a business-grade access point. – Zac67 May 28 '17 at 16:04
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    Consumer-grade devices are explicitly off-topic here. – Ron Maupin May 28 '17 at 16:06
  • Additionally, a "simple" wifi network is a single AP/router and up to 5 or maybe 8 clients. What you're describing is far beyond simple, provided the expected traffic is more than next to nothing. – Zac67 May 29 '17 at 15:16
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Although I do agree with Ron and Zac's answers, I would also like to give input myself to see if it may help you. First, I want to tell you what to do to assess your current wireless network, then advice on designing a new wireless network for that auditorium. Before you make any changes, turn SNMP on on ALL of your network devices and make sure all of the management IP addresses of those network devices (not the wireless clients nor your laptop) are STATIC and not DHCP. Next, download a Multi Router Traffic Grapher. Next, make your laptop WIRED if you can because you don't want that network's wireless problems to interfere with your laptop's ability to gather information. Once your devices are in there and running, wait until the hall is crowded. When the problems begin, look at your graphs for either bandwidth saturation, client overload, etc. It is there that you will be able to assess what problem you're having. Keep in mind, you may be having more than one problem at the same time.

Now for the part that stings the pocketbook a bit that Ron and Zac already mentioned - business-grade hardware. With that, you will be able to advance your wireless network to one that can control things like how much bandwidth you will permit to each user (aka bandwidth throttling), deauth attach prevention, bonding, load balancing, etc. Prepare for a pricetag and yearly maintenance (software upgrade) costs with business-grade hardware.

Now to comment on parts of your post. You mentioned that you have a 50x50 auditorium with 200 seats. From a design perspective, here are two of the biggest factors to consider. One, your 200 seats can be assumed as 200 wireless clients. On average, depending on your hardware, an access point can handle 25 associations (25 devices). 200 divided by 25 is 8. So at a MINIMUM, you need 8 access points to meet maximum thresholds. I recommend going with at least 10 to give yourself some breathing room. Two, multiple access points in a 50x50 area can create a hostile environment if using 2.4GHz antenna's. Here's why. In America, the 2.4GHz range will support three channels. 1, 6, and 11. Meaning, each ap may have only ONE channel. So if you have only 3 ap's, no problem. If you have more, then logically you will have a channel that has multiple access points using it within range of eachother. This causes CO-CHANNEL INTERFERENCE, which results in poor wireless performance for the clients. To avoid this, get the access points that have antennas in the 5GHz range. You have many more channels so you can avoid this problem. Also SPACE OUT YOUR AP'S APPROPRIATELY. If your 200 clients are evenly spaced, your ap's should be as well.

Your 10Mb internet circuit may be questioned as well for 200 users, depending on what they're doing. Without bandwidth throttling per user, you could theoretically have a couple of users streaming and steal the bandwidth from the others. Your SNMP graph on the internet interface of your internet router will tell you clearly if 10 is enough.

To answer the question about what a wireless session is, in short it is a client connection through the access point to a destination. See https://en.wikipedia.org/wiki/Wireless_Session_Protocol. So for example, if you have a client that opens a browser and goes to Google, then Yahoo, they have two sessions taken up.

  • Product or resource recommendations are explicitly off-topic here, as they are on most SE sites, except Software Recommendations and Hardware Recommendations. – Ron Maupin May 29 '17 at 15:08
  • @Tom, thanks for the detailed information and tips. They will certainly help. One thing that puzzles me all this time is how loading balancing works for wifi. Even if there are 10 APs, how would the clients distribute themselves evenly? As everyone enters via the main entrance, wouldn't all lock onto the one nearest the entrance in the first instance? Does the protocol accommodate roaming to get the "highest quality" signal? – Old Geezer May 30 '17 at 6:01
  • Hey, I'm glad it helped. So load balancing would be used if you have a critical need for network access. For example, a good design would be to have two wireless controllers that both act as primary in a HA pair (HA=High Availability). They would be configured to balance the load for network usage. But to answer the question you're really getting to, when your clients enter the room, they would associate to the strongest ap, then as they disperse and get near other ap's, they reassociate. So if you spread your ap's out evenly based on crowd dispersion, the crowd will associate accordingly. – Tom May 30 '17 at 12:13
  • CORRECTION to my last comment. When I stated HA pair, I should have said ACTIVE/ACTIVE pair. A High Availability pair is when you must have a connection. So if one controller dies, the other automatically picks up the load. No load balancing with HA. Howerver, with an ACTIVE/ACTIVE pair of controllers, (depending on the manufacturer) both will work together to balance which ap's they serve and how the traffic gets moved. But they will ALSO act as a failover to eachother. The downside is the cost of access point licenses just doubled. So choose wisely on your hardware purchase. – Tom May 30 '17 at 12:44
  • Just one more question to your comment one above the last: in a small room of 50'x50', would the wifi signal from the APs differ by that much as to cause disassociation and reassociation to a nearer AP? – Old Geezer May 30 '17 at 15:54
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Usually you would hire an expert to perform a wireless site survey to give you proper WAP quantities, placements, frequencies radio power, etc. You could use business-grade WAPs and a WLC to control and adjust them all.

Also, 10 Mbps may not really be enough if all 200 people are trying to use the WAN connection at the same time. You should use something that can tell you specifics. For example NetFlow, or one of its variants.

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