woody Posted February 20, 2008 Posted February 20, 2008 We are moving towards being an academy for September and we have been asked to discuss the possibility of giving every child an Eee PC with windows on. As you know there are lots of issues involved with this such as battery life, security etc etc, but I just want to concentrate on the scale of wireless that will be needed for this. Here's the scenario. Each pupil will have a personal device such as the Eee PC. They will take it to every lesson. That means there will be 25-30 pupils accessing the network in one classroom. And there will be 60+ classrooms in use at any one time. Can we realistically provide enough coveridge and bandwidth to cope with that? What about roming? What about availability and probable conflict of channels? If you have faced this discussion before, or better still implemented such a system, I'd be very interested to know! I want to be positive about what they are suggesting, but I need to be realistic too. Thanks
Jona Posted February 20, 2008 Posted February 20, 2008 Sounds epic, could you look at putting in wired network points to each desk and /or power. Either way you need a lot of infrastructure investment... Don't forget to consider if your current IT support staff can cope with supporting 1500 extra machines, or if you need to hire some more people. Also does your backbone have enough capacity (wireless issues aside) to cope with the increased traffic?
tri_94 Posted February 20, 2008 Posted February 20, 2008 Hi there Mark, personally i think that is a big ask from wireless however yes it totally possible at a price. What you'd need to look into is a "wireless switch" They are about and they sort out the wireless at switch level and therefore you don't get any issues of having two wireless units near each other causing a blackspot where a signal cant be reached. With a wireless switch you'd need to network cable to each room and connect and to the network point you plug in a areal or on the 3com one its a 3com access point. and example of the type of system i'm talking about is the address below http://www.vnunet.com/personal-computer-world/hardware/2184654/review-3com-3crus2475-wireless would be happy to explain a bit more about the system, if you think it would help. tri_94
broc Posted February 20, 2008 Posted February 20, 2008 Seriously, I would contact some very BIG players in the Managed Wireless Networking business (Cisco, HP) and ask them to explain how they would do it, and then insist upon reference visits to see it in action on this sort of scale. Quite frankly I would hate to be the first to try it, regardless of what the client device would be. As part of BSF, my school & LA are very keen to achieve 1:1 student to computer ratios so I would be keen to see this in action myself. One other question I would be tempted to ask relates to Health and Safety. Has any research been done into the effects (if any) of having such a high density of low-powered wireless devices in such close proximity?
plexer Posted February 20, 2008 Posted February 20, 2008 Yes it's possible but you need to employ the services of some specialists to give you the best kit for your needs. Something that can give you multiple access points per room with proper load balancing. Speak to people like react technologies who supply the aruba solution. Ben
SimpleSi Posted February 20, 2008 Posted February 20, 2008 I would do some rough estimates based on 2 expensive AP's per teaching area needing covering (15 clients /AP). Gigabit wiring to each classroom. Replacement central switches. Then double this and add in cost of eeePCs. Guess at additional staff to run it. Submit this as 1st estimate and ask if they want you to proceed any further the school would have to pay for a proper survey. Also explain geometric risk equation i.e Computers don't work properly yet. Wireless doesn't work properly yet. Chance of computers and wireless working properly = Computers chance * Wireless chance (multiplied by pupil factor of course ) regards Simon
wesleyw Posted February 20, 2008 Posted February 20, 2008 Okay there are several big players in the market that could handle this kind of demand. Cisco, HP, Extricom, Aruba and Colubris. There are others such as Extreme but the first five I should think would be the best options. Extricom is a fantastic unit and unique I believe their APs are usually a combined unit of two or even four radio modules with only one network point to wire back (they'll also buy the kit back when the N standard comes out reduced cost of course ) every radio unit within the same SSID is on the same channel (their unique feature) conflicts do not happen Extricom are the only company I know of that create single channel wireless clouds if you're going to have that sort of network device density this may be the best solution for you have a chat with G4 they guarantee a working solution from their design and placement if it doesn't they'll come in a make it at their own expense if it still can't be made to work they'll refund you all the money. Have a chat with Dave Allen. I am currently running Aruba but we are having problems currently with the WPA encrypted access guest is fine but the normal user SSID doesn't work with anymore than a few laptops at a time and you'll need this. I suggest you ask all of the companies that will be tendering for this to come in and setup a no cost trial for 1 - 2 weeks minimum they can setup the units install everything on the servers and this will allow you to see which of the solutions works or works best! Wes
Ric_ Posted February 20, 2008 Posted February 20, 2008 I know I am writing this guide for everyone but a deployment of this size needs 100% coverage and redundancy - otherwise the shed-loads of cash you have spent on the eeePCs becomes unusable when your wireless controller of APs breakdown - as such you need to get some of the big guys in to spec it up. You need to compare all the big names too - Cisco, Aruba, BlueSocket - and do not cut corners.
windy Posted February 20, 2008 Posted February 20, 2008 (edited) Of course it can be done it's just a matter of cost. We put in a cisco 4400 wireless lan controller last summer supporting 50 AP's ( 36 in use) I do beleve that the lan controllers can be 'bolted togther' to give you as many AP's as you require. Since it went in it has been faultless. Will all the laptops be in use at once? Will all the classrooms be in use at once? Most of the big players kit will hand off connections between AP's to load balance connections between all avalible AP's. Are you expecting all the laptops to connect connect at 54meg? If so you'll need a lot of AP's! The company we used did a free wireless survey for us so we had a relistic idea of how many AP's we'd need to achive a certain throughput. If you want I can give you the name of the company we used? They were great and support us all through the planning any installs. Regards Marc Edited February 20, 2008 by windy Add name
wesleyw Posted February 20, 2008 Posted February 20, 2008 Judging from the sheer size of your system I would think you'll need 2 APs minimum per room this will be thin APs so price will be around £250 - £300 per point. Aruba APs will work regardless of how many switches lie between them and the Aruba controllers Extricom APs need a direct connection so you are looking at around 120 APs just for classrooms this will equate to three 2400 Aruba Controllers I think they do larger capacity units as well (not sure of their price however) say £6000 for each unit around £48,000 for the lot add about another £18,000 the fact you'll need more Extricom units as they need direct connections. 1500 eeePCs? £180 each £270,000 total of around £318,000 minimum then there is the wiring (power and network for controllers) and possible new cabinets for the controllers £50 per point 123 points (Network) and 3 (power) overall price is going to come in around £6,300 then look at how many techs are going to be needed? BECTA suggest is around 100-200 PCs per tech so between 7 -15 techs yeah right you may get two or three so that is an extra £30,000 - £45,000 a year for their salaries. Putting power into the rooms instead would mean 1500 power points and the same network points using HP Switches this will be £70,000+ the power and network points will cost £150,000 and this is only if the distribution boards will take it otherwise you'll need new supplies bought in. I'd budget around £600,000 for everything if the latter needs doing as a minimum. This isn't going to be cheap and the ongoing costs incurred for the power consumption is something I would also look into. You'll need to look at charging the eeePCs and the cost of extra batteries and if there is anyway you'll be able to charge that battery outside of the laptop? Lots of points to consider. Another way at looking for the systems via wireless would be a Thin Client solution. I've got a rather long winded project plan and costing document I sent to our head in regards to options okay our school is about half the size but it may prove useful anyway PM me and I'll send it you. Wes
CyberNerd Posted February 20, 2008 Posted February 20, 2008 With all this talk of wireless, don't forgtet to beef up your server infrastructure - fileservers, vle, email and authentication servers may need an upgrade
Butuz Posted February 21, 2008 Posted February 21, 2008 Wow - 1500 Eee PC's and site wide wireless. Sounds like a recipe for low reliability - and MASSIVE TCO to me! Good luck with this one! Butuz
woody Posted February 22, 2008 Author Posted February 22, 2008 Yeah, thanks for all the advice guys. It is important to go over the figures at a basic level and see if that puts the management off the idea. Then if they come back and say 'do it' then you can start worrying about how it will work. I would have to bring in one of the big comps to manage the whole process, and put some redudancy into the package in case it doesn't work. We have already been stung once with a failing wireless network so need to get this one right from day one. Will keep you informed how things go.
sysman Posted February 25, 2008 Posted February 25, 2008 I'm technical support in a large high school. We have technology status and are always looking at new computer things. The school has classrooms where they use 30 laptops and we found traditional wireless just couldn't cope. We have gone with Extricom in one building and found it works brilliantly and will this summer be rolling it out across 4 larger buildings. I can recommend you look at this solution but think earlier posts suggestin g you will need 2 access points per room is about right. We have only planned the wireless with signal strength should be good from 3 access points which has give us an average of 1 point per room but not everyroom. This technology is simple but clever, have a look even get your technical staff to speak directly with Extricom and they will do there best to help you out. (They are the new boys in the arena and keen to impress)
m25man Posted February 26, 2008 Posted February 26, 2008 1500 Eee PCs accessing wireless? Should this not be in the Flying Pigs Section of the Forum? or the, Ooh! I've just found £20k left over in my IT budget what shall I waste it on now section!
localzuk Posted February 26, 2008 Posted February 26, 2008 1500 Eee PCs accessing wireless? Should this not be in the Flying Pigs Section of the Forum? or the, Ooh! I've just found £20k left over in my IT budget what shall I waste it on now section! 20k? We've got quite a small school, which would need around 25 AP's and a managed wireless system would cost us in excess of £50k including all the infrastructure needed to run it... £20k won't get you much...
stevehead Posted March 3, 2008 Posted March 3, 2008 Hi, just joined, and I've just installed an Extricom system this weekend in a very small Primary School. I had the pleasure of a very generous budget to provide 'visionary' IT into 4 classrooms and an 8 station computer suite. The story so far... The school already has 8 failing XP Workstations, 25 WiFi XP Laptops less than a year old and 8 staff WiFi Laptops. They get 2 hours a week support from the local Community College - that's it! So first off to keep things manageable I installed a hefty Terminal Server with Virtual CD ROM Services. Onto this I loaded up all the Curriculum Software and CD Images. Then beefed up the infrastructure by replacing 100Mbps Hubs with Gigabit Switches. Replaced all 8 XP Workstations with Wyse TCX Multimedia Enabled Terminals (the V10L). No more hassle in the Computer Suite! Installed 2 X Extricom 404 Units (8 dual channel radios). The radios are co-located, 2 in each classroom. There are 4 available channel 'blankets'; 1, 6, 11 in 2.4GHz and CH36 in the 'A' Band. Into this radio swamp, I'm throwing another 38 Linux EeePC's (4Gb / 512Mb), all on 2.4GHz. (I did try installing a a/b/g card into the EeePC, but gave up as impractical.) Staff Laptops are all on the 'A' Band. The EeePC... these run the standard 'Easy Mode' Xandros which has been modified to remove any customising features to stop tinkering but MUCH more importantly, have 2 new Icons in 'Work'. These are both Terminal Services Icons, which connect the EeePC to the Curriculum Terminal Server. One is an Internet Shortcut optimised for connecting from home, and the other is a Network Shortcut, optimised for WiFI LAN Connections. The Terminal Server connection allows pupils to login to their Windows Domain to access all data and Windows Apps, and maps the EeePC Document folder to My Computer for moving files to and from the EeePC's if needed. I can't complete this story because, well, you try sourcing 38 EeePC's. Coming Mid March apparently. I do expect the Extracom Network to support 50 odd WiFI devices densely packed into the 4 classrooms in a random arrangement; if Extricom can't do it then I'm stuffed! Note that this is much tougher than standard XP Laptops which just 'blip' the network when requesting web pages etc. All 38 EeePC's will be hitting the Terminal Server constantly - a bit like 38 VOIP Calls that never end. Will it work, or will it collapse in a pile of marketing guff? Tune in next month...... 2
SimpleSi Posted March 4, 2008 Posted March 4, 2008 @stevehead Would you mind reposting (or the mods could split it off) this in another thread as there are some many interesting issues to discuss in your post that wouldn't be relavent to this thread regards Simon
Butuz Posted March 4, 2008 Posted March 4, 2008 Good post Steve - be really interested to hear how you get on. Interesting idea thin clients over wireless - shouldnt be too much traffic overall, but yes it will be constant and sustained traffic. Butuz
stevehead Posted March 4, 2008 Posted March 4, 2008 Mod: Plz move if I'm causing this thread to go OT. Interesting idea thin clients over wireless Butuz Yeah I've really grown just a bit fond of 'em. I have issues with the way schools are buying more and more laptops 'cos even though they're cheap these days, they give poor value due to low availability. About 6 months ago I put 15 Thin Client Laptops into another little school. These are called NEC TCM160's - look like a laptop but boot from a flash disk and run XPe. These have been incredibly successful. First and foremost is battery life. They come out of the charging trolley at 9.00 and run all (school) day on battery. Now that's good value. Once set up, these can't be messed with so zero maintenance. Staff Training consisted of "make sure the radio is on and it's charged". The school also has 2 suites of Wyse V10L wired Thin Clients, so the kids see exactly the same desktop etc. whether they have a portable or not. For wireless support, I moved all existing laptops up onto the 'A' bands and run 2 'b/g' band Linksys AP's in designated areas for decent connectivity. I was very lucky with the layout of the school as I managed to get quite a clean set of overlaps. The TCM160's all work together and quickly too. Wouldn't work on a large site though, so back to Extricom for you guys with campuses to contend with. The EeePC will tread a bit lighter on my network due to it's small screen size as screen data Updates are smaller.
strawberry Posted March 4, 2008 Posted March 4, 2008 i know your not looking for recommedations but i've got a company coming in to do a site wide wireless survey, happy to give you details if you want.
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