In this article, I am going to cover the top two things that are often overlooked when planning what is considered the most essential part of any BYOD or 1:1 initiative: The Wireless Network. Everyone would agree that the wireless network is the most visible portion of any type of classroom networking technology initiative. Most teachers, students and parents have a Netgear or Apple AirPort in their home that works quite nicely for them, and think that wireless in a school is exactly the same thing. If you have not heard it before now, I'm here to tell you it is not -- not even close. There are a vast number of things to consider when deploying a wireless network in a school environment that do not apply to your home. And today's article will tackle the two biggest items that most school's overlook or do not plan for appropriately. They are the wired network and capacity planning.
The Wired Network
If you walk into any school you will get a myriad of responses about how good (or bad) the network is. Some people will tell you it is fine, others will complain that it is slow and still others might have periodic complaints. If you think that is bad -- try throwing a wireless network on top of that, and see what you get from your constituents. They complaints will simply magnify if you haven't done your homework. So what constitutes a "good" network? I'm not sure there is any one answer that is more detailed than one that allows for the users to do what they need to do, in a reasonable amount of time, with limited to no downtime due to network failures. What does that mean? That is different for every institution. However, the one constant is that it should always be online and available for use. And there are some minimum considerations when thinking about a wired network that is built to support wireless and BYOD or 1:1.
On your wired network, each user (generally) has one device per network port. Yes, sometimes phones or other
devices will share a port, but if you averaged it out you would likely happily round it down to one device per port. If that is not true, IE: you have one port per room with ten port hubs in each classroom, then stop what you are doing and address that now. The answer may be, "When we install wireless they all go away," and that is fine. But you must have a plan for fixing those glaring issues. One wired device per port, period.
Your wired network should have the capability of delivering 1GB of bandwidth to your wireless access points. Why? Because unlike your wired network which only has one device per port, the one port that you plug in your wireless access point to will be serving anywhere from 1 to 30 devices at the same time. Like it or not, 100MB simply is not going to do the trick. That does not mean you have to necessarily upgrade your entire network, but you will need to ensure that the wireless access points are plugging into the GB ports.
Your wired uplinks between closets and buildings must be bigger than 1GB. Yes, you read that right. Ideally, you'd have fiber between all buildings and closets. That is not always possible. If it is not, you'll switching equipment capable of multiple GB connections aggregated together to allow for more than 1GB of bandwidth to leave the location and travel towards its destination. With some fiber connectivity ramping up to 10GB, it is certainly something to look into. And small enterprise class GB switches can be had for as little as $400 each for 48 ports. It does not have to cost you a fortune, but it will cost something.
Your Internet connection must be beefy enough to support your users needs. I can't stress this enough. The bulk of your classroom traffic in the future is going to be going out to the Internet. Users will be storing things in the Cloud, they will be accessing databases in hosted environments and watching YouTube videos. The model of User to Server to User is dead. If you aren't already planning for this -- you need to now before you spend money on a robust wireless system that gets bottled up at your Internet connection. What is adequate? Well the answer depends on your use, but there is no school that can survive on less than 20MB download and 10MB upload anymore. And that is certain not ideal. Most Internet providers are capable of offering 50MB of guaranteed bandwidth to you at a reasonable price. And when I say reasonable, I mean at a fraction of what that T1 or T3 is costing you now. Get ride of the T1/T3, save your school some money and be an Internet hero immediately. Do your best to stay about from the $50 or $70 a month "business class" connections. Most providers do not guarantee any bandwidth with those connections, so your performance will vary. But -- hooking up to a 20MB guaranteed fiber Internet connection with a "business class" cable modem as a backup is a great plan. It offers a lot of bandwidth with a backup in case of an outage. In this area, this combination can cost as little as $500 per month. Compare that with the $1200 your paying for one T3 at a fraction of the bandwidth.
Putting all of these things together will enable you to support just about anything your teachers, students or administrators can throw at your network.
Capacity Planning
OK, here is another GOTCHA in the wireless network planning world. You've walked around... done a wireless survey and figured out how many access points you need to cover your classrooms. BUT, have you thought about how many devices are going to be in each classroom? Or auditorium? Or even the gym? In 2009, The Gartner Group reported that the average person has 1.6 wireless devices on them at any time. In 2012, they upped that to 3. That's 3 devices per user, per location. That means that if you have an average class size of 20 students, plus your teacher -- you could have as many as 63 devices in that one classroom hitting at your wireless access points. One of the biggest pitfalls that I've seen is when a tech coordinator says, "This access point is covering these 4 classrooms." And when I ask what the average class size is and then do the math for them, it quickly explains why their wireless network access is spotty and sluggish.
So when you are talking to wireless integrators it is important to note the coverage, but also how many devices that the access point can handle at one time. The things to consider with that are the frequencies -- is this wireless access point 5GHZ capable? This is important because every access point on the market today will support 2.4GHZ, which is that most common frequency. And there are up to 13 usable channels in the 2.4GHZ frequency range, while the 5GHZ frequency has up to 50 usable channels. Now, these numbers are different based on the hardware and software being used to run the access point. For instance, some vendors use one of those channels in order to broadcast between each other to check for usage. So, it is important to ask your wireless vendor about this. This is important because no two wireless devices can use the same channel at the same time. A good enterprise level wireless network will move things around, and only use the channel for the actual amount of time that the device needs it -- but you can still see that the 5GHZ frequency allows for a lot more flexibility than the 2.4GHZ. It is also important to note that you can't necessarily tell if an access point supports 5GHZ simply by the protocols used. 802.11b and 802.11g use the 2.4GHZ range exclusively, while the 802.11a protocol uses the 5GHZ band exclusively. But, the 802.11n can use both. That means that if you are buying 802.11 b/g/n access points, you are likely only getting the 2.4GHZ range, while the 802.11 a/b/g/n will include the 5GHZ frequency. It is worth noting that the 802.11ac protocol only functions in the 5GHZ range.
The other big thing to consider when sizing the wireless network is the number of radios in the access point. For instance, if you have 2 radios that are 802.11 b/g/n access points you can probably comfortably support 15-20 devices at any one time. If you have 3 radios, you kick it up to 25-35 at one time. If you have 802.11 a/b/g/n radios you can probably move those numbers up into the 50s comfortably - as long as your wired network can support that kind of throughput. It is worth noting that the better 802.11 a/b/g/n access points have more than one network port on them. If you get those, you can push 2GB per access point. So, you can see how this bandwidth quickly adds up?
I hope this has proven to be helpful and educational while you are thinking about your BYOD, 1:1 and wireless network. Please feel free to post any questions or follow up to this below. I'm happy to answer!
~~~~~Bruce has worked in educational technology for over 17 years and has implemented several 1:1/BYOD programs. He also has been a classroom teacher for various subjects. Bruce is the author of five books: Sands of Time, Towering Pines Volume One:Room 509, The Star of Christmas, Philadelphia Story: A Lance Carter Detective Novel and The Insider's Story: A Lance Carter Detective Novel. He also has a new novel coming out in June 2014, The Kill Commission. Follow Bruce's Novel releases by subscribing to his FREE newsletter!
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