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Best WAP For Dense Crowds?
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."
You don't have to hit 'em, mate. Just find another crowd that's brighter.
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?
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.
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.
WAP = Wireless Access Point.
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.
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.
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.
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).
BlackNova Traders
and here's the press release about the Australian Open, whose organizers said
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.
-ted
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. http://store.xirrus.com/SearchResults.asp?Cat=4
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?
Seriously, try Meraki. Their software is pretty neat, and it'll auto configure to give you the best situation.
A case study: http://meraki.com/general/2009/12/09/does-it-scale-absolutely-blazing-fast-meraki-wireless-at-leweb-conference-in-paris/
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.
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.
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.
Seriously.
Guns don't kill people, "with glowing hearts" kills people.
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).
Never trust anyone who takes pride in being called a 'geek'....
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.
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.
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 http://www.airwave.com/resources/demos/ 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.
I have read very good recommendations of having cells of WIFI routers giving 1,4,7,11 in one, 2,5,8,12 in another and 3,6,9 in the third, why lock yourself in?
In Japan, you can use all the 14 WIFI channels, and if your event is the ONE TIME thingy, use all 14 channels !
Do a 1,5,9,13 on router A, then 2,6,10,14 on router B, then 3,7,11 on router C and 4,8,12 on router D on group them into one cell.
Try push all the users of router C and D to 5 GHz band, router B to 3.6 GHz band and router A to 2.4 GHz band.
Use directional antennas, aim router A to North, router B to East, router C to South and router D to West.
Then set up cells within the premise.
In that way the signals that overlaps are not of the same channel, and not in the same frequency band either.
Muchas Gracias, Señor Edward Snowden !
There are plenty more Adolfs out there other than the infamous Hitler...
Wow, that's a string of misguided replies, with the occasional person that actually knows what they're talking about. Full disclosure: I'm an engineer for Aruba Networks, and this is exactly the kind of thing I/we do regularly. I've personally done the Interop shows in Javitts Center in NYC, the All-Star Game at Yankee Stadium, and various other conferences with 1,000 or more people. As a company, we've done the wireless network at Black Hat for years (without one failure or hack), the HoPe conference, as well as most of the hotels and conference centers in Vegas. Oh yeah, and every US Air Force base in the world. If you want this to work, here are the unique features that ONLY Aruba Networks provides for high density deployments (all without needing software on the clients or CCX extensions in the NIC card)...
- Band Steering: Use dual-radio access points. The Aruba gear detects if a client supports both 2.4g and 5g, and moves the client automatically to the 5g band, which is cleaner and has more channels available.
- Spectrum Load Balancing: Every vendor offers load balancing: there are 10 users on AP-1/Channel 1, and 20 on AP-2/Channel 6, so put the next user on AP-1. This ignores the fact that the only resource you're really constrained by is the amount of spectrum in use, not the number of users on an AP. If those 10 users are using most of the spectrum of Channel 1, while Channel 6 isn't being used as heavily by the 20 users, you'll get better performance by balancing the user to the less-utilized spectrum, rather than the lowest user-count AP.
- Co-Channel Interference: The Aruba architecture knows when a client is within range of two APs on the same channel, and schedules transmissions out of the APs so they don't collide in the air.
- Adjacent channel interference: Aruba ecognizes that there *will* be some bleed between transmissions on adjacent channels, and manages transmissions to avoid that.
- Airtime Fairness: Aruba recognizes the different client phy types (802.11a, b, g, and n-2.4/n-5) and allocates certain amounts of airtime to each client, so those old 11b clients don't drag your 11n clients to a screeching halt.
- Channel Reuse: modifying the collision threshold on the channel to allow you to reuse channels in much closer proximity to one another than normally possible.
- Dynamic Multicast Optimization: The APs can detect a multicast stream and determine if it's better to send the stream to all multicast clients at one, but at the normal lowest data rate, or convert the stream to a series of unicast transmissions that can be sent to each client at a much higher rate.
- Mode-aware Adaptive Radio Management: Deploy as many APs as you want. The Aruba architecture will automatically turn on (or off!) individual radios based upon RF needs; too much RF is worse than not enough, in most cases.
- Client bandwidth contracts: Set a rate limit for each user, so one person can't use half your bandwidth.
- Policy Enforcement Firewall: Allow your users to only do what protocols you want (http, https, dhcp, dns), and block all the others. iTunes/Bonjour/MulticastDNS from Apple products will KILL your network otherwise.
If you want more information on the physics of these methods, check out this white paper which has more info than you'll want to read:
http://www.arubanetworks.com/pdf/technology/whitepapers/wp_ARM_EnterpriseWLAN.pdf
Now, all of that said, here are some BAD ideas that people have suggested:
- Use all 14 channels!
------ Not only is this illegal almost everywhere, but most clients will use the operating system's country code and only use the channels that are supposed to be available. In the U.S. for example, only channels 1-11 are valid; client devices won't try to use channels 12-14.
- Use channels 1, 4, 7, 10 on one group of APs, then 2, 5, 8, 11 on the next set....
------ TERRIBLE idea. Because 802.11a
-- You can't drink all day. (Unless you start in the morning...)