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Best WAP For Dense Crowds?

timothy posted more than 4 years ago | from the well-phrased-and-specific dept.

Wireless Networking 178

An anonymous reader writes "A local community organization has asked me to help them set up Wi-Fi access for an upcoming event, with some unusual (to me) requirements. All users (up to 500 people) will occupy a relatively small area and more-or-less have line-of-sight to the WAP, so issues like signal strength and wall penetration don't matter. Security also does not matter, as we plan to open this to anyone wanting to connect. Cost always matters, but we realize a $50 Linksys or three won't cut it here. In the past, I have used Cisco AP1200s for a few dozen users to great satisfaction, but they only handle 50 connections at a time, and practically count as antiques at this point anyway. My research on the matter tells me that 802.11n performs far better in this regard, but I want to support 802.11g as well. I have no objection to using two APs to split those apart (with n limited to 5.8GHz, as per the suggestion of several comments in a recent Ask Slashdot), but physical constraints make it preferable to minimize the total number of APs needed — Ten WRT54s might cost about the same as one Aironet, but I only have three good places to mount these. I welcome any suggestions and real-world experiences with similar situations, including the ever-popular Ask Slashdot refrain of 'What kind of idiot would do it like that, when you can just do this?' Ideally, I would like to know model numbers and how well they held up under real-world loads comparable to my situation."

cancel ×


WAP? (0, Flamebait)

Chris Lawrence (1733598) | more than 4 years ago | (#31378170)

I thought WAP was dead with real mobile browsers?

Re:WAP? (0)

Anonymous Coward | more than 4 years ago | (#31378208)

I think he meant Wireless Access Point ;)

Re:WAP? (4, Informative)

KiwiSurfer (309836) | more than 4 years ago | (#31378216)

WAP = Wireless Access Point.

Re:WAP? (1)

Chris Lawrence (1733598) | more than 4 years ago | (#31378316)

Bad attempt at a funny. But if you have to explain...

Re:WAP? (1)

KiwiSurfer (309836) | more than 4 years ago | (#31378348)

I knew it was a joke! :)

However your joke pointed out that some people might now know what WAP stands for in this context, so I thought I would just put out the definition for those that might not know.

- James

Re:WAP? (1)

Chris Lawrence (1733598) | more than 4 years ago | (#31378388)

Fair enough then, happy to hear I didn't have to resort to a smiley!

Re:WAP? (1)

adolf (21054) | more than 4 years ago | (#31378510)


Re:WAP? (0)

Anonymous Coward | more than 4 years ago | (#31379350)

*Sigh* Invoking Godwin's law should require more than merely visiting a thread. You've gone and taken all the fun, creativity, and vitriol out of it...

Re:WAP? (0)

Anonymous Coward | more than 4 years ago | (#31379364)

I thought WAP was dead with real mobile browsers?

I still use Palm OS 5, you insensitive clod!

Best WAP For Dense Crowds? (5, Funny)

theolein (316044) | more than 4 years ago | (#31378182)

You don't have to hit 'em, mate. Just find another crowd that's brighter.

Re:Best WAP For Dense Crowds? (0)

blankinthefill (665181) | more than 4 years ago | (#31378296)

I'm so glad I'm not the only one who had this thought.

Re:Best WAP For Dense Crowds? (-1, Redundant)

Phantasmagoria (1595) | more than 4 years ago | (#31378606)


Re:Best WAP For Dense Crowds? (0)

Anonymous Coward | more than 4 years ago | (#31378678)

I was thinking a wireless access point wouldn't be that great a melee weapon in a dense crowd of zombies.

What's the event? (3, Insightful)

rolfwind (528248) | more than 4 years ago | (#31378190)

Will all 500 users connect at the same time and continuously (like some type of LAN party w/o the LAN) or is this much more haphazard and random with far less users at any one time?

Re:What's the event? (4, Funny)

MichaelSmith (789609) | more than 4 years ago | (#31378318)

And why wasn't I invited?

Re:What's the event? (1)

Nikker (749551) | more than 4 years ago | (#31378772)

Common man after the last time ... the lamp shade, two Chihuahuas and the weed waker, do you really have to ask?

Re:What's the event? (1)

FatdogHaiku (978357) | more than 4 years ago | (#31378992)

You know of a device that awakens weeds? Or is this a person, like "The Rain Maker"? Rain making, useful. Weed waking, not so much... unless you can make them march on a location... Then it's "Pay me or your golf course will be unplayable in the morning, BWAH-HA-HA-HA-HA!!!

A story about crazy behavior at a party (1)

Futurepower(R) (558542) | more than 4 years ago | (#31379222)

This: "Common man after the last time ... the lamp shade, two Chihuahuas and the weed waker, do you really have to ask?"

was meant to be a story about crazy behavior at a party:

"Come on, man... After the last time... The lamp shade, two Chihuahuas, and the weed whacker, do you really have to ask?"

Re:A story about crazy behavior at a party (1)

gd2shoe (747932) | more than 4 years ago | (#31379374)

There seems to be an echo in here.

Oh, and please compare:
waker []
wacker []

Re:What's the event? (1)

93 Escort Wagon (326346) | more than 4 years ago | (#31379342)

the lamp shade, two Chihuahuas and the weed waker,

The Weed Waker - isn't that the new Zelda game?

how cheap? pfsense? (4, Informative)

itzdandy (183397) | more than 4 years ago | (#31378202)

consider running a small pfsense box with a number of wifi adapters. You could pick up some cheap directional antennas to help limit connections to any one radio somewhat. Alternatively you could just run 4 sids and do a script to hide a sid when the user count got so high so the next users would only see the less loaded ones.

Re:how cheap? pfsense? (4, Informative)

itzdandy (183397) | more than 4 years ago | (#31378214)

I might add that you are going to be stuck with 4 channels ( 1,4,7,10 ) which means that 500 people will be hard to support without highly directional antennas. Maybe try to split the space into 4 with directionals.

Re:how cheap? pfsense? (1)

mrcaseyj (902945) | more than 4 years ago | (#31378328)

You might want to select USB wireless devices that have as much of the firmware running in the host as possible to avoid overloading the little microcontrollers that are built into the radios. You might also want to have a bunch of cat5 cables hanging around the perimeter of the place in case people who need the net cant get it wirelessly.

sounds like Xirrus. But I'd recommend... (2, Informative)

Anonymous Coward | more than 4 years ago | (#31378330)

Directional antennas is the Xirrus approach. They have a cute little niche in auditorium-type deployments, too.

But I'd say, a few Aruba AP-105s [] (with 802.11abgn and band steering - which tries to put clients on the 5Ghz band), or maybe even AP125s [] (which have more MIMO) for the core. You can fill in the corners with cheap little AP-65s [] . The ARM (adaptive radio management, shoves clients from one AP to another or something like that) means that Aruba works very well in dense deployments. (You'll also need a controller behind them... probably an Aruba-200 or a 651 - the latter has a built in AP. Having the controller limits the configuration you'll need to do.)

I work for Aruba, but I never look at a price list. I believe, however, the pricing should be rather competitive with Cisco .... Also, I'd cite some super awesome deployments and customers but I forget who's a super awesome reference customer that my parents would recognize and who's just "a major hospitality win in the Middle East" (which is so much less impressive-sounding!) here's their press release page anyway [] .

p.s. if running cables is a problem... (2, Informative)

Anonymous Coward | more than 4 years ago | (#31378406)

If running network cables to some point is a problem (you mentioned limited places to mount APs) note that the Aruba gear can do mesh. So you could have some 5GHz backhaul to the places that you have power but can't do a cable run. I think a mesh license costs you extra, though.

and here's the press release about the Australian Open [] , whose organizers said

We have more than 1,500 journalists, photographers and producers on site that require reliable, time-critical access to the network, and they have been getting best-in-class service.

Re:how cheap? pfsense? (2, Insightful)

jonsmirl (114798) | more than 4 years ago | (#31378384)

Use simultaneous dual band APs. Push everyone possible to 5Ghz.

Re:how cheap? pfsense? (5, Informative)

Anonymous Coward | more than 4 years ago | (#31378434)

I did a little googling because I was worried about the number of clients. 802.11 uses CSMA which means that every client must wait for every other client to go silent before transmitting.

That means that you would have to take the minimum latency and multiply it by 500 since all clients will be equals. That puts you into 500ms of theoretical latency per packet.

What this means practically is that with 500 clients using all roughly the same bandwidth at 54Mb (unrealistic BTW) you would have just 110Kb per second available to each with 500ms+ latencies, which will compound exponentially.

Though on paper you might be able to show that ability to connect this many clients but realistically, on HIGH end hardware your are going to have a 50 client MAX simply because of CSMA requiring everyone to take turns but less any bandwidth sharing.

To make things worse, the amount of data having to be moved just to keep everyone connected and to communicate who is 1st,2nd,3rd, etc in line to speak is going to cut your bandwidth to a tiny fraction of the link speed.

I highly suggest that you take one of the early poster's advice and drag some cat5e around. You might have some lucky with 'CELLS' of WRT54g type routers with a carefully selected channel scheme where a set of 4 routers would have channels 1,4,7,10 and the next closest 2,5,8,11 and the next 3,6,9 and then start over. The channels will overlap somewhat but having 11 SSIDs for 500 people even with some channel interference would get you to somewhere around 50.

you could extend that to put some 5Ghz band routers in each router bunch and hope that people are fairly evenly split between G and 5Ghz N

Re:how cheap? pfsense? (1)

jeffstar (134407) | more than 4 years ago | (#31378624)

i would mod you up had i not already commented

Re:how cheap? pfsense? (2, Funny)

Drantin (569921) | more than 4 years ago | (#31379360)

Yes, we should be able to mod people up to remove our comments.

Re:how cheap? pfsense? (0)

Anonymous Coward | more than 4 years ago | (#31378792)

You reasoning is incorrect. You are assuming 1ms per "hold message" unicast to each client before allowing one to transmit? Every part of that assumption is incorrect. 1ms, unicast, all clients equal, 1 AP for all contention.

A little knowledge is very dangerous.

Re:how cheap? pfsense? (0)

Anonymous Coward | more than 4 years ago | (#31379080)

You misinterpret what he is saying. He is NOT saying that every client needs to receive a hold message so there is 500ms of hold message time. What he is saying is that if each client has to take turns transmitting, and you have 500 clients, that you have to wait for the 499 clients before you to do their transmit before you can do yours.

So if every client takes 1ms to transmit, then you have a revolving 500ms transmit window where you can transmit your message. Hence the 500ms of latency that was mentioned.

I don't know if any of this is actually true, but that is what the GP appears to be saying.

Re:how cheap? pfsense? (2, Interesting)

besalope (1186101) | more than 4 years ago | (#31379232)

Hence why the OP was looking into multiple WAPs. If he has 3 WAPs with clients ideally spread between them it would drop to ~166 clients/WAP and which would lower latency and improve potential speeds. Unless this is a very tech-heavy crowd 'N' might not be overly prevalent in people's notebooks/netbooks/pdas. And if the N routers are performing in mixed mode performance would be hindered. 1 centralized MIMO N with peripheral G (mimo if possible) would segment a bit better while allowing each technology to run in its native specification for best performance.

Re:how cheap? pfsense? (3, Interesting)

afidel (530433) | more than 4 years ago | (#31379354)

Well, I would use true dual band WAP's and have the 5Ghz radios setup for 802.11a with an SSID per channel. 802.11n 5Ghz radios are fully backwards compatible with 802.11a.

you will need more than 2 APs (5, Informative)

jeffstar (134407) | more than 4 years ago | (#31378204)

there was a slashdot the other day about the wifi at a python conference.

any AP is only going to handle 50 users or so because 802.11x is contention based.

So go ahead and get yourself 10 APs, spread them out, and make sure the ones near eachother are on different channels.

Re:you will need more than 2 APs (2, Interesting)

adolf (21054) | more than 4 years ago | (#31378400)

He's only got physical room for three access points (or, more likely: three clusters of access points).

There are three non-overlapping channels. So, 3 channels * 3 clusters = 9 APs, maximum. But 9 APs * 50 users each 500.

It's important to remember that 50 is just a useful number, and needn't be a hard limit: It's not spelled out in 802.11 that "there shall not be more than 50 users per node."

And besides, it's not like folks are going to physically locate themselves for optimum WiFi distribution. They'll be wherever they are. There's always going to be more than, or less than, 50 users per access point eventually, no matter what. Nevermind the fact that even running in a somewhat degraded state, these 9 independent access points are NOT going to be the bottleneck -- the backbone to Teh Intarwebs will be.


1. Use three clusters of three WRT54GL (the L suffix is important, in case the asker doesn't know -- Google it), all running OpenWRT or Tomato or somesuch freewheeling firmware.

2. Turn the power down. Lots. More power means that the contention issues of 802.11 get worse, not better. A bit of low-tech experimentation with a couple of devices (any old laptop, a jailbroke iPod Touch, an Android phone, etc) will help find the sweet spot for power in that environment.

3. ???

4. Profit!

Re:you will need more than 2 APs (-1, Offtopic)

Anonymous Coward | more than 4 years ago | (#31378464)

it's not like folks are going to physically locate themselves for optimum WiFi distribution.

What is Optimum WiFi? []
Optimum WiFi is a collection of thousands of Internet access points in public locations that allow you to connect to the Internet at super fast speeds just as easily as you can connect with your wireless router at home. Our Optimum WiFi community zones are available in shopping centers, on main streets and train platforms, in parks, marinas, and at sports fields - the places you go everyday. We are growing quickly and adding more locations everyday so check here often to stay up to speed. And best of all, its FREE for Optimum Online customers.

Re:you will need more than 2 APs (1)

Kral_Blbec (1201285) | more than 4 years ago | (#31379290)

And besides, it's not like folks are going to physically locate themselves for optimum WiFi distribution. They'll be wherever they are.

They will if they are any sort of nerd who has done any wardriving. Don't tell me you have never held your laptop vertical in just the right spot out the car window to get a connection.

Re:you will need more than 2 APs (5, Informative)

Vancorps (746090) | more than 4 years ago | (#31379346)

Or buy two Xirrus units which are all in one turn-key arrays of access points all that will auto-tune for you. They have a 16 access point and an 8 access point versions that would handle this setup without any problem.

Mikrotik a possible choice? (4, Interesting)

lordsilence (682367) | more than 4 years ago | (#31378226)

Even though they're suspected GPL offenders (opinions differ) I still have to put in my word for mikrotik. These guys know how to build wifi in rural areas with plenty of subscribers, stable hardware and good software at low cost. Even their cheaper products are very well up to the task and can be expanded upon with different wireless-transmitters and antennas. If that is not enough you can always look at their more "enterprise:ish" products. I've only good things to say about them, and we used their products for well over 5 years when we still ran a WISP.

Re:Mikrotik a possible choice? (1)

jeffstar (134407) | more than 4 years ago | (#31378378)

mikrotik is cheap, and flexible, and can do lots of things, but there are lots of advanced features that only work half way, half the time, or are half-way documented.

if you are going to keep it simple, or don't mind spending hours reading old forum threads then it might be the way to go!

Re:Mikrotik a possible choice? (3, Informative)

tagno25 (1518033) | more than 4 years ago | (#31378398)

try Ubiquti instead for just an AP (or CPE)

Choices (3, Interesting)

the eric conspiracy (20178) | more than 4 years ago | (#31378322)

I have a Netgear WNDR3700 that I use as an access point. It has a lot of good features including two independent radios (2.4 and 5 GHz), gigabit switch and a pretty fast processor. It is about as good as it gets for hardware of its type.

The firmware based on OpenWRT. Some of the features like the attached storage are dodgy, but that doesn't matter for this application.

For your application though - high density, lots of users why don't you take some of the load off the airwaves by offering wired connections too? People who aren't actually physically roaming will appreciate the choice and better performance of wired.

Re:Choices (0)

Anonymous Coward | more than 4 years ago | (#31378478)

That looks like a really nice unit. I'd be tempted to get one for personal use as well as for small to medium business applications.

If you were going to go a step or two higher end than that unit what did your research turn up as the best alternatives, and in what ways
were they better? I'm thinking of a light commercial small business infrastructure sort of application where I'd want like four or five
of these sorts of units to cover a large factory floor sort of area going into a commercial LAN backbone, but on a relatively low budget (startup).

Easy! (0)

Anonymous Coward | more than 4 years ago | (#31378342)

Setup some inexpensive ipfire ( boxes with wlan cards. Can be used, older hardware and the distro is free.

Xirrus (0)

Anonymous Coward | more than 4 years ago | (#31378362)

I would suggest

Asus RT-n16 (2, Informative)

Ron Harwood (136613) | more than 4 years ago | (#31378380)

Run your favourite 3rd party firmware on it (openwrt, dd-wrt, tomato, whatever) - it's specs are pretty awesome for the bucks. 128M Ram, 32M flash, two usb ports, N wireless, 480Mhz Broadcom/MIPS cpu (~twice as fast as most others).

Re:Asus RT-n16 (2, Interesting)

phizi0n (1237812) | more than 4 years ago | (#31378890)

The RT-N16 is 2.4GHz only which will be terrible for this scenario. The OP needs to use dual band routers to utilize both bands and maximize the number of clients that can be supported in a small area. 2.4GHz only has 3 non-overlapping channels and if you figure 50 per channel then that's 150 users for 2.4GHz. The 5GHz range has far more usable channels and the majority of N adapters can utilize either band.

Aerohive (1, Informative)

Anonymous Coward | more than 4 years ago | (#31378418)

You may want to look into Aerohive. If you are interested in pricing or more technical information let me know

Meru Networks (4, Informative)

zerofoo (262795) | more than 4 years ago | (#31378430)

Not the cheapest stuff, but Meru's access points and controllers will allow you to run all the APs on one channel, and the controller "load balances" the users across the available access points within reach of the client.

We use them at my place of employment (6 APs scattered throughout the building servicing around 200 laptops), and the performance is quite good.


Aruba Networks. (0)

Anonymous Coward | more than 4 years ago | (#31378528)

Not the cheapest stuff, but... well, $marketing says that of the Adaptive Radio Management []

  • Band steering - actively guides faster 802.11a/n clients, and even specific applications or users, to the best available wireless channel. The result is better noise immunity, fewer sources of interference, and more available channels. If a client supports both 2.4GHz and higher speed 5GHz bands, this feature will automatically direct it to the 5GHz band for best performance;
  • Spectrum load balancing - enables Aruba access points and Multi-Service Mobility Controllers to dynamically shift Wi-Fi clients to access points on channels with available bandwidth. This technique is intended to prevent degraded network performance due to over-subscription;
  • Coordinated access - coordinates access to a wireless channel, across all access points that share that channel, to overcome the challenges of densely populated deployments such as lecture halls, airport lounges, and conference centers;
  • Co-Channel Interference Mitigation - access points with excess capacity reduce RF transmissions by reverting to air monitor mode;
  • Airtime fairness - scheduled access for dense deployments delivers equal access to all Wi-Fi clients. This feature works with all 2.45GHz and 5GHz Wi-Fi clients, regardless of its wireless chip manufacturer or standard operating system supplier; and
  • Performance protection - prevents higher speed clients using 802.11n from being compromised by slower 802.11b/g clients.

Not cheap, but... (5, Informative)

mmccarn (1760806) | more than 4 years ago | (#31378432)

Xirrus 'Arrays' are designed for what you're doing. I've used 2 4-radio Xirrus arrays to serve 240 users in a single ballroom. []

ballroom surfing (2, Funny)

jandoedel (1149947) | more than 4 years ago | (#31378584)

So you put 240 people in a single ballroom, and all they do is surf the web?

Why..? Did you forget to turn on the music?

Re:ballroom surfing (1)

daveime (1253762) | more than 4 years ago | (#31378774)

239 of them are male, and the 1 potential "other" has a mustache.

Anyway, joking aside, have you seen kids today in a net cafe or Starbys ? Even when they're there with friends, they don't talk to each other, they IM each other via Facebook.

Re:ballroom surfing (1, Funny)

Anonymous Coward | more than 4 years ago | (#31379018)

No, they're texting because they're making fun of the faggot who calls it Starbys.

Re:ballroom surfing (1)

Nikker (749551) | more than 4 years ago | (#31378840)

Sounds like a Slashdot wedding to me...

Re:Not cheap, but... (2, Informative)

Manuka (4415) | more than 4 years ago | (#31378756)

I'll second the Xirrus arrays. They're absolutely amazing for high-density wireless. If it's a one-time event, you may be able to get Xirrus to sponsor it by providing the gear, especially if it's a gathering of geeks.

Re:Not cheap, but... (1)

bidule (173941) | more than 4 years ago | (#31378820)

I read bathroom and started to wonder...

Re:Not cheap, but... (5, Insightful)

Kizeh (71312) | more than 4 years ago | (#31378952)

The parent means Xirrus will cause the event organizers to mortgage a house. Still, Xirrus can have tons of radios in one device, all with segmented antennas, and they really are a good fit for this kind of stuff. They even have a pole/tripod mounting option where you can set up more if need be. See about the sponsoring or maybe renting.
Alternatively, get external 60 degree segment antennas for something like Cisco 1250s and do hexagonal cells, like wireless carriers do. For dual band MIMO you need six antennas per AP, so it'll get out of control mighty fast.
Worst case, get a bunch of APs, have three of them use the three 2.4 GHz channels with MIMO (but no channel bonding!) and as many 5 GHz ones as you can, since you have many more non-overlapping channels to work with. Chances are that anyone stuck on 2.4 GHz is going to hate life. Plan power levels as well, and don't run radios hotter than they need to be, despite the temptation.
Also, very, very important: DISABLE LOW DATA RATES. Mandate 5 or 11 Mbps as the lowest supported rate at all the radios. Otherwise the 1 Mbps Nintendo DS's and phones will eat up all the airtime and starve everyone of access. If you can get away with turning off 802.11b support and only offering 802.11g on 2.4 GHz, do so.
Finally, ignore any comment suggesting consumer gear.

Re:Not cheap, but... (1)

adelporto (104675) | more than 4 years ago | (#31379312)

Second everything Kizeh says. I run wireless for 400 - 1000 person tech conferences and use a combination of Xirrus arrays (generously donated) Cisco APs and Meraki APs. The Arrays are perfect for high density wireless without a lot of supporting infrastructure. Of course, I couldn't use them if they weren't donated.

One tip I heard from another person who runs tech conference networks is to place the APs under the chairs if you have to support a very dense room. POE would be really helpful there, and the 1200s do it on EOL'd Catalyst switches, but unless you have the extra radio you'll be missing out on 5GHz, and you really really really want 5GHz. Unless you're really lucky, the venue will probably have wireless installed or nearby that will encroach on the 2.4GHz channels you want to use, but there is very little 5GHz gear deployed.

Oh, and don't think about things like mesh; you want those radios dealing with client traffic once, not relaying it.

You haven't mentioned what you're going to do to route the traffic, hand out DHCP and resolve DNS. If you can, run two DNS boxes forwarding to the ISP's resolvers. Slow dns makes an oversubscribed network worse. If you're using a PC for the router, use Gigabit network cards - they handle lots of packets better than 10/100 cards.

Good Luck!

What about Ubiquity? (1)

az1324 (458137) | more than 4 years ago | (#31378436)

Ubiquity Rocket M2 and M5

Scalability: 300+ subs per sectored base station

Re:What about Ubiquity? (1)

jeffstar (134407) | more than 4 years ago | (#31378504)

that is only when ubiquity clients are used, not ordinary 802.11n cards.

Re:What about Ubiquity? (1)

ProfessionalCookie (673314) | more than 4 years ago | (#31378566)

Not to mention a company that will test your setup in their lab if you have a problem and live on OSS principles. Great people! It's also cheap reliable hardware. []

Anonymous (0)

Anonymous Coward | more than 4 years ago | (#31378466)

Xirrus is the way to go... I've done this before and nothing else has worked, especially Cisco. We have standard Xirrus conference kits at work ready to be quickly deployed for this kind of thing. Reasonably priced too.

Xirrus XN8 (0)

Anonymous Coward | more than 4 years ago | (#31378482)

The Xirrus XN8 not a cheap option, but it will work for over 500 simultaneous users with b,g,n using only the one device.

Ubiquiti Bullets (0)

Anonymous Coward | more than 4 years ago | (#31378526)

Ubiquiti (, makers of WISP hardware, have a "Bullet AP" product that is extremely affordable and VERY easy to set up. It's great in dense environments and you BYO antenna so you could set up 2 or 3 with panel antennas at a central location to cover the entire area, effectively load-balancing your geography.

Re:Ubiquiti Bullets (1)

ProfessionalCookie (673314) | more than 4 years ago | (#31378592)

Or just use Picostations, which is a bullet with an RP-SMA instead of an N type and a built in omni. But really with many users it seems like Rocket+Sector Antennas is the way to go, yeah?

not that unusual (1)

so-logical (802444) | more than 4 years ago | (#31378564)

What you are describing is basically the situation faced by every conference with more than a few hundred people. Everything is fine when you are in break-out rooms or smaller sessions, but put everyone together in a ballroom, add a boring keynote speaker (probability: high), and wireless becomes unusable. Especially geek conferences when every person in the room has a laptop and a iPhone. Or two. The usual solution is large numbers of WAPs and let the proles self-regulate which WAP they connect to: if they can't get one one, they'll try, try again until the connect.

Stop using infrastructure mode, moron (0)

Anonymous Coward | more than 4 years ago | (#31378582)

use Adhoc. no problems then. eesh.

Meraki (2, Informative)

dotwaffle (610149) | more than 4 years ago | (#31378588)

Seriously, try Meraki. Their software is pretty neat, and it'll auto configure to give you the best situation.

A case study: [] -absolutely-blazing-fast-meraki-wireless-at-leweb-conference-in-paris/

Re:Meraki (1)

G Money (12364) | more than 4 years ago | (#31378794)

I have to second the Meraki, I've worked with them a little and they are stupid simple to setup and maintain. From a price perspective they kill Cisco and a lot of the other big vendors as well so it can be a big win all around.

Ruckus AP's (1)

TrouserMonkey (1513867) | more than 4 years ago | (#31378602)

You will have to email them to get the Prices, but you could get all 500 of them by just using three of these. I can tell you from my own experience these will definatlly do the trick each once can handle 200 concurrent connections and have enough speed to run HD IPTV's off them if you wanted. []

Re:Ruckus AP's (1)

mFriedy (1363405) | more than 4 years ago | (#31378870)

I'd also suggest a Ruckus AP. My company (a public access internet provider) uses these for any site which expects and decent amount of usage. They have both internal and external APs, and really good meshing and management functionality.

Security DOES matter (0)

Anonymous Coward | more than 4 years ago | (#31378612)

remember that they will all be able to listen to each other's traffic.

airport extreme (4, Funny)

saleenS281 (859657) | more than 4 years ago | (#31378676)

It won't have anywhere near the granularity in configurations, but I will say apple airport extreme's tend to "just work". They support both g and n operating at the same time since they have multiple antenna's, and they also have a sort of sandbox guest environment you can set.

If you want fall-down easy to setup and manage, they'll get the job done. If you want granular control, don't waste your time. I got sick of trying to make dd-wrt work with WAP, wireless-n and g at the same time a year ago, and just bit the bullet on the apple units. I can say it's been one purchase I don't regret.

Re:airport extreme (0)

Anonymous Coward | more than 4 years ago | (#31379090)

*rolls eyes*

Re:airport extreme (2, Insightful)

gmthor (1150907) | more than 4 years ago | (#31379318)

how many clients have ever connected to your airport extreme? This is definitely not the right device for the described setting.

Hey, move your elbow! (1)

SEWilco (27983) | more than 4 years ago | (#31378696)

They're going to use laptops in the mosh pit?

consumer equipment is the wrong answer (5, Informative)

Anonymous Coward | more than 4 years ago | (#31378716)

Background on me to qualify my comments: I am a cisco engineer specialising in wireless and security. My product recommendations later come from this experience but there are other products capable of the same performance such as the aruba equipment which would be my close second recommendation but i have no specific product knowledge.

I think you need to refine your requirements. It is highly unlikey that a crowd of 500 people will create 500 connections. You will probably end up serving 100-150 clients simultaneously but not all of them requesting data at the same time unless there is something specific that all users need to connect to at the same time throughout the event.

Without much better information everyone is just throwing out a product, not a design. And as you clearly are not a wireless expert (as you asked for 802.11n "as well as .11g) i would recommend finding someone who is to consult properly.

And for those suggesting consumer products, your dreaming. Without some form of spectrum management in this situation the asker is doomed to provide a very poor service with no roaming and massive 2.4ghz congestion. In addition, those people recommending wired access, WTF? You very clearly do not understand what you are talking about. Are you expecting 500 desks with RJ45 ports, or multiple 48 switches places around the room for people to huddle around with their laptops (and only laptops as no mobile device even has an RJ45 port). This is clearly a fallacious argument.

Answer the following questions and we can all get very specific.

3 points to place APs. Is this to physically mount or a cabling limitation? Can you mount more but have no cabling? Un-manged switches can help with this for less than $50 each. If only to mount then you are stuffed, There is nothing out there that will handle 500 clients with any useful service. It's not a limitation of the products it's the contention of the medium as mentioned earlier.

What services are they accessing? Are they local or is it just the internet? If the internet, what is the upstream bandwidth available? If local access at high speed (100Mb/s +) then you will end up with contention issues. If it is the internet and the pipe isn't fat you are not looking at contention issues you are looking at number of users connected. Most modern APs do not have practical limits of associated clients but most recommend around 25 per AP.

What is the nature of the event? Basically, are you providing a service that is required constantly throughout the event leading to 100% of attendees connecting all the time. Also, are users accessing a high bandwidth service (streaming video for example) all the time or things like static web pages delivered via http? The later will deliver small amounts of data to each person but will then take time to read by the attendees al will also be cached locally meaning subsequent connections will require even less bandwidth. If streaming video, someone should have though of this earlier and you will need a consultant/engineer 100% or expect to fail.

An off the cuff answer without the above knowledge assuming http type data required, cabling limitation not mounting, the more realistic 150 simultaneous users and internet link at less than 30Mb/s:

1x Cisco 2112 Controller (100Mb ports not important as limited upstream)
5-9x Cisco 1142 APs (very nice 802.11n dual band with the ability to force people to move to 5Ghz if they have it 6.0+ code)
3x gigabit unmanaged switches (something like dlink DGS-1005D)

It would not be far fetched to contact decent size Cisco/Aruba/VendorX partner and get loan equipment for a price + a consultant as part of the deal.

Re:consumer equipment is the wrong answer (1)

egcagrac0 (1410377) | more than 4 years ago | (#31378796)

AC knows his stuff. Pay attention. (I have no mod points today. :( )

+1 on renting an expert and equipment to help assure the event is a success, and not a headache because nobody can get online.

Re:consumer equipment is the wrong answer (1)

Panaflex (13191) | more than 4 years ago | (#31378864)

I'd say this is the best answer so far. To be a bit more precise - it really depends on how many people and how reliable you want to be.

A professional event (well paid) should definitely consider getting a real setup - you can rent the equipment and get a setup as part of the deal.

However, if this is a less formal event (e.g. free or near free), then you could probably get by with 3-4 good AP's, some directional antennas, turn the power down, and spread the channels out. Good luck!

Aerohive (1)

macintard (1270416) | more than 4 years ago | (#31378734)

Check out Aerohive ( These guys use to work at Juniper/Netscreen. It's a controller based solution that runs CentOS with a MySQL backend. The APs themselves run Linux too. If the APs lose connectivity to the controller, they can still function. You can do 802.11x auth. Good stuff.

Aruba Networks = Wireless Win (2, Informative)

Redlazer (786403) | more than 4 years ago | (#31378736)

I work for a wireless network company in Vancouver. We use Aruba extensively, as it's extremely flexible, powerful, and easy to use.

The chains of Cisco are removed, and an extraordinarily simple setup process - which will help you figure out AP placement and type, after uploading a site map, including all sorts of calculations that I'd really have a computer do.

I seriously recommend you take a serious look at Aruba Networks offerings.


Baseball bat (1)

kimvette (919543) | more than 4 years ago | (#31378742)

Baseball bats work quite well against one or two. Any more waps than that, you'll need to look for an alternative.

HP/Colubris (2, Interesting)

sigipickl (595932) | more than 4 years ago | (#31378744)

HP ProCurve has dual radio products from their buyout of Colubris... check out the MSM422. You can run 2-3 of these @ low to mid power with one radio on N (@ 5ghz) and one on b/g (channelized). That should split the traffic up a bit (most newer laptops have 802.11n cards) You should be able to get 200+ users per AP as long as no one tries to connect from the parking lot (hence the low power).

You can also use some narrow-field sector antennas and "columnize" your signals across a room.

If it is a more permanent installation, consider a distributed/engineered antenna solution (DAS) that will limit the signal bleed outside the intended area (and in turn, increase the connected capacity of the AP. DAS solutions get expensive though. So unless you have other signals you want to inject (cell, licensed radio, etc...), this may be out of the cost range you are looking at.

And for the record, I work for an HP reseller (we sell/support other vendors as well).

pycon conference example (0)

Anonymous Coward | more than 4 years ago | (#31378758)

Checkout the recent pycon conference setup. They had luck with 5.2GHz wireless A+N using netgear hardware. 600 clients.

Why are you buying? (1, Interesting)

Anonymous Coward | more than 4 years ago | (#31378760)

I hope you're not planning on buying anything when a better way to do things would be to rent/lease/hire some equipment for the job. Which is hard to place, since you gave so few details. 500 people, but what, if any networking connection will they need? What is the real intent here? I can understand being a little vague, but there's a point where it's hard to help, and it really seems like you're expecting a magic solution to waft you way.

Won't happen.

My Pick (2, Informative)

huzur79 (1441705) | more than 4 years ago | (#31378776)

Setup 12 Airport Extremes Each one supports 2 different antennas plus a guest network. You can setup a group of them as N Only on 5Ghz, N Only on 2.5Ghz, G Only, B Only and maybe even setup one of them as A Only. Reasons I picked this 1, if you set WAPs up in N on 2.4Ghz with backwards compatibility it only takes one user on B to nock every one down to B. 2, There is a 50 User limit on WAPs 3, you get 24 networks with 12 devices, and you can space out the B,G and N 2.4Ghz networks over a few channels and have true 5ghz N and A there too. 4, They are high performance devices and reliable and easy to manage as a group. The other problem you will face is IP addresses. You will need to set that up to since you can only have 253 IPs on a class C subnetwork. Another reason I selected the Airport Extremes is you can build a wireless Network backbone so you dont have to string up cables between all of them. You can use the spare antenna on a few of them to connect to each other.

Re:My Pick (0)

Anonymous Coward | more than 4 years ago | (#31378856)

This is such a bad idea it's not funny.

You mix physical signal amplification up with logical network configuration and then you create so many networks and expect non tech savy people to know which one they need to connect to? A 2.4Ghz .11n device can connect to 3 of those networks. Should the user know which one? They wont.

1 SSID over multiple connected APs is the ONLY way to succeed. The overhead of anything else = fail.

Trapeze!!! (1)

awrz (1009247) | more than 4 years ago | (#31378780)

My firm loves and adores Trapeze WAPs. You can get MIMO units that are PoE powered for far less than the competition *cough* *cough* Cisco.

We have one prominent client (an IT admin who runs a large school campus) who swears by Trapeze WAPs.

Check them out: link []

Keep in mind that only the best WAPs can only handle so many clients at once! You're going to need to have multiple WAPs on multiple channels in your area to make this work.

Best WAP? Easy... (0)

Anonymous Coward | more than 4 years ago | (#31378830)

2x4 upside their's amazing what some incentivizing can do to improve collective intelligence

Dense Crowds (1)

hackus (159037) | more than 4 years ago | (#31378910)

You need to give us the following to help you:

1) db Antenna specs on the AP's
2) Area you would like to cover in cubic meters.
3) Are the sender and receivers using the same 802.11 spec or do you plan on mixing the environment?
4) Is this line of site for all of the receivers or are there obstructions?

Personally I have had excellent results with the WRT600. Nice big processor and decent antennas 802.11N, DD-WRT.
(You can modify the case to make better interfaces for Antennas...just google for it.)


Xirrus (1, Interesting)

Anonymous Coward | more than 4 years ago | (#31378928)

Take a look at Xirrus access points... they're designed for high density applications.

However, they are expensive.

the best type of setup for that sort of thing... (1)

sxpert (139117) | more than 4 years ago | (#31378944)

the best solution is to set up a lot of APs with very very low power and low gain antennas all over the room, in bridge mode, all with the same frequency and SSID, all connected to the same lan, and sprinkle them all around the room.

I've had very good results with Ubiquity picostation 2 attached to the chairs in a keynote style setup (one stage and plenty of chairs...

as for how it works, easy...
the "low power" part, takes care of there being a lot of people. laptop will connect to the closest ap (aka best received signal), so the lower the power the ap puts out, the less laptops it will attract (which will take care of the "I can't handle more than x people at a time part)
as for the bridging, frequency & ssid setups, this will allow for complete transparent roaming around the covered area.

ps: can I enquire what the event is ?

turn of 802.11b!!!!! (2, Interesting)

Anonymous Coward | more than 4 years ago | (#31378946)

I addition to my other comments...

Turn off 802.11b. Very few devices still use it but if you enable it the backwards compatibility mechanisms will slow the network to a crawl. It is usually done by disabling the speeds 1, 2, 5.5 and 11Mb/s.

In such close proximity and no signal strength issues i would also recommend making sure you add higher basic rates ( i have no idea what vendors other than cisco call it) as if everyone is connecting faster (whether or not there is more throughput is irrelevant) then this will up the management and control traffic to a higher rate freeing up even more spectrum.

Compatibility for all (1)

skudenfaugen (808335) | more than 4 years ago | (#31379028)

802.11n is compatible with all of the previous specs (a,b and g) even though they didn't all talk to each other. Mixed mode (2.4 and 5GHz to the rescue). Here are a couple links that should help explain (yes I know these are older but these should help get the idea across). [] and []

Ruckus Wireless (0)

Anonymous Coward | more than 4 years ago | (#31379056)

Check out Ruckus Wireless. The dual band APs can handle 200 users each, and cover a 5000 square foot area each. They can be installed with or without a controller. Extremely easy to set up and they come with a lifetime warranty.

They have 17 directional antennas inside them and we have yet to find an environment where they did not out preform the competition; very strong signal and cut through interference like it isn't there.

We've been replacing Aruba, Cisco, and Meru products with Ruckus for many clients that have become frustrated with how difficult their existing gear was to install and manage. All of our clients are very happy with the Ruckus gear.

Linksys routers with simultaneous dual band (1)

WarJolt (990309) | more than 4 years ago | (#31379060) []

It should be less than $160 and will probably give you the best performance when using N. Never tried it though.

half-duplex (0)

Anonymous Coward | more than 4 years ago | (#31379286)

check out prior art how to cater wireless to hundreds of network users, and consumer grade hardware isn't what you want

The Two-Tier Internet, Delivered by Anton Kapela

Aruba (3, Interesting)

mixmaster (748142) | more than 4 years ago | (#31379288)

Saw a presentation of the new Aruba 3 OS last week, and also got a demo of the AirWave used in the Aruba headquarter. This is a very good solution if you want to have full control and it's an event that you want to have control over and maybe have them on a regular basis. Could be that it's an overkill for this kind of event, but take a look here [] to get a some new thoughts. It can also give you a heatmap of the coverage of all your AP's around in the event area.

Meru Networks... or cisco/Juniper/foundry/Extreme (1, Interesting)

Anonymous Coward | more than 4 years ago | (#31379324)

I would do a controller/WAP and possibly a router for everyone to authenticate too. But then again, 500 users on wifi is like beating a dead horse... Nothing beats hard wiring to every user. I would say if this is something like a large business, large RV park, Apartment complex, etc, I say bite the bullet and invest in the right hardware to do the job. Consumer grade products are not going to get you anywhere. So enterprise grade or bust here. You can probably run fiber optic to each corner and a few in the middle, connect to a small switch and hard wire where ever or attach your WAP and run them 100M in what ever direction.Shielded cat6 comes to mind for this task.

Good luck setting up 500 users on Stable wifi in the same community, because if you can do it, patent the method...

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