The Wireless Density Problem

March 21, 2013 — netequalizer

Recently, we have been involved in several projects where an IT consulting company has attempted to bring public wireless service into a high density arena. So far, the jury is out on how effective these service offerings have fared.

The motivation for such a project is driven by several factors.

1) Most standard cellular 4G data coverage is generally not adequate to handle 20,000 people with iPhones in a packed arena. I am sure the larger carriers are also feverishly working on a solution, but I have no inside information as to their approach nor chance of success.

Note: I’d be interested to learn about any arenas with great coverage?

2) Venue operators have customers that expect to be able to use their wireless devices during the course of a game to check stats, send pictures, etc.

3) Public frequency, wireless controllers, and access points are getting smarter rather quickly. Even though I have not seen clear success in these extremely high densities, free wireless solutions are gaining momentum.

We are actually doing a trial at a major sports venue in the coming weeks. From the perspective of the NetEqualizer, we are invited along to keep the  primary 1GB Internet pipe feeding the entire arena from going down. To date we have not been asked to referee the mayhem of access point regional gridlock and congestion in an arena setting, mostly because of of our price point and cost to deploy at each radio.

Why do these high density roll outs fail to meet expectation?

It seems, that 20+ thousand people in a small arena transmitting and receiving data over public frequencies really sucks for access points. The best way to picture this chaos would be to imagine listening to a million crickets on a warm summer night and trying to pick out the cadence of a single insect. Yes you might be able to single out a cricket  if it landed on your nose, but in a large arena not everybody can be next to an access point. The echoes from all the transmissions coming in to the radios in these high densities are unprecedented. Even with an initial success we see problems build as usage up take rises.  If you build it they will come! Typically what happens is that only a small percentage of attendees login to the wireless offering on the initial trial. The early success is tempered as usage doubles and doubles again eventually overwhelming the radios and their controllers.

My surprising conclusion

My prediction is that in the near future, we will start to see little plug in stations in high density venues. These stations will be compatible with next generation wireless devices, thus serving up data to your seat. You may scoff, but I am already hearing rumbles from many of our cutting edge high density housing internet providers on this issue. Due to wireless technology limitations they plan to keep their wired portals in their buildings, even in areas where they have spent heavily on wireless coverage.

Related Articles:

Siradel.com radio coverage

Addressing issues of wireless data coverage.

How to speed up access on your Iphone

Posted in Bandwidth Management. Tags: , , , , , , . 1 Comment »

More Ideas on How to Improve Wireless Network Quality

October 30, 2012 — netequalizer

By Art Reisman

CTO – http://www.netequalizer.com

I just came back from one of our user group seminars held at a very prestigious University. Their core networks are all running smoothly, but they still have some hard to find, sporadic dead spots on their wireless network. It seems no matter how many site surveys they do, and how many times they try to optimize their placement of their access points, they always end up with sporadic transient dark spots.

Why does this happen?

The issue with 802.11 class wireless service is that most access points lack intelligence.

With low traffic volumes, wireless networks can work flawlessly, but add a few extra users, and you can get a perfect storm. Combine some noise, and a loud talker close to the access point (hidden node), and the weaker signaled users will just get crowded out until the loud talker with a stronger signal is done. These outages are generally regional, localized to a single AP, and may have nothing to do with the overall usage on the network. Often, troubleshooting is almost impossible. By the time the investigation starts, the crowd has dispersed and all an admin has to go on is complaints that cannot be reproduced.

Access points also have a mind of their own. They will often back down from the best case throughput speed to a slower speed in a noisy environment. I don’t mean audible noise, but just crowded airwaves, lots of talkers and possible interference from other electronic devices.

For a quick stop gap solution, you can take a bandwidth controller and…

Put tight rate caps on all wireless users, we suggest 500kbs or slower. Although this might seem counter-intuitive and wasteful, it will eliminate the loud talkers with strong signals from dominating an entire access point. Many operators cringe at this sort of idea, and we admit it might seem a bit crude. However, in the face of random users getting locked out completely, and the high cost of retrofitting your network with a smarter mesh, it can be very effective.

Along the same lines as using fixed rate caps, a bit more elegant solution is to measure the peak draw on your mesh and implement equalizing on the largest streams at peak times. Even with a smart mesh network of integrated AP’s, (described in our next bullet point) you can get a great deal of relief by implementing dynamic throttling of the largest streams on your network during peak times. This method will allow users to pull bigger streams during off peak hours.

Another solution would be to deploy smarter mesh access points…

I have to back track a bit on my stupid AP comments above. The modern mesh offerings from companies such as:

Aruba Networks (www.arubanetworks.com)

Meru ( www.merunetworks.com)

Meraki ( www.meraki.com)

All have intelligence designed to reduce the hidden node, and other congestion problems using techniques such as:

  • Switch off users with weaker signals so they are forced to a nearby access point. They do this basically by ignoring the weaker users’ signals altogether, so they are forced to seek a connection with another AP in the mesh, and thus better service.
  • Prevent low quality users from connecting at slow speeds, thus the access point does not need to back off for all users.
  • Smarter logging, so an admin can go in after the fact and at least get a history of what the AP was doing at the time.

Related article explaining optimizing wireless transmission.

Posted in Bandwidth Management, Wireless Internet. Tags: , , , , , . 2 Comments »

How to Speed Up Your Wireless Network

October 19, 2012 — netequalizer

Editors Notes:

This article was adapted and updated from our original article for generic Internet congestion.

Note: This article is written from the perspective of a single wireless router, however all the optimizations explained below also apply to more complex wireless mesh networks.

It occurred to me today, that in all the years I have been posting about common ways to speed up your Internet, I have never really written a plain and simple consumer explanation dedicated to how a bandwidth controller can speed a congested wireless network. After all, it seems intuitive, that a bandwidth controller is something an ISP would use to slow down and regulate a users speed, not make it faster; but there can be a beneficial side to a smart bandwidth controller that will make a user’s experience on a network appear much faster.

What causes slowness on a wireless shared link?

Everything you do on your Internet creates a connection from inside your network to the Internet, and all these connections compete for the limited amount of bandwidth on your wireless router.

Quite a bit of slow wireless service problems are due to contention on overloaded access points. Even if you are the only user on the network, a simple update to your virus software running in the background can dominate your wireless link. A large download often will cause everything else you try (email, browsing) to come to a crawl.

Your wireless router provides first-come, first-serve service to all the wireless devices trying to access the Internet. To make matters worse, the heavier users (the ones with the larger persistent downloads) tend to get more than their fair share of wireless time slots. Large downloads are like the school yard bully – they tend to butt in line, and not play fair.

Also, what many people may not realize, is that even with a high rate of service to the Internet, your access point, or wireless back haul to the Internet, may create a bottle neck at a much lower throughput level than what your optimal throughput is rate for.

So how can a bandwidth controller make my wireless network faster?

A smart bandwidth controller will analyze all your wireless connections on the fly. It will then selectively take away some bandwidth from the bullies. Once the bullies are removed, other applications will get much needed wireless time slots out to the Internet, thus speeding them up.

What application benefits most when a bandwidth controller is deployed on a wireless network?

The most noticeable beneficiary will be your VoIP service. VoIP calls typically don’t use that much bandwidth, but they are incredibly sensitive to a congested link. Even small quarter-second gaps in a VoIP call can make a conversation unintelligible.

Can a bandwidth controller make my YouTube videos play without interruption?

In some cases yes, but generally no. A YouTube video will require anywhere from 500kbs to 1000kbs of your link, and is often the bully on the link; however in some instances there are bigger bullies crushing YouTube performance, and a bandwidth controller can help in those instances.

Can a home user or small business with a slow wireless connection take advantage of a bandwidth controller?

Yes, but the choice is a time-cost-benefit decision. For about $1,600 there are some products out there that come with support that can solve this issue for you, but that price is hard to justify for the home user – even a business user sometimes.

Note: I am trying to keep this article objective and hence am not recommending anything in particular.

On a home-user network it might be easier just to police it yourself, shutting off background applications, and unplugging the kids’ computers when you really need to get something done. A bandwidth controller must sit between your modem/router and all the users on your network.

Related Article Ten Things to Consider When Choosing a Bandwidth Shaper.

Related Article Hidden Nodes on your wireless network

Posted in Bandwidth Management, Network Speed, Wireless Internet. Tags: , , , , , , , . Leave a Comment »
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