Tuesday, May 26, 2009

Our Equipment

I've compiled all the equipment we are using for our deployment. I hope it is informative!


We bought 4 WRT54GS's from Circuit City (now kind of a division of Tiger Direct, you can buy from either one and get the same price, there was a promotion on circuitcity.com so we bought from there) to act as switch's and Access Points.

We were given a server. The motherboard from the server's specs can be seen here.

The rest of the specifications of the server are as follows:

SolidLogic GS-L02 Fanless Mini-ITX System
- Mainboard: EPIA LN10000EG 1GHz
- Case: Serener GS-L02 Fanless Mini-ITX Case - Black
- Memory: DDR2 667 RAM 1GB
- Hard Disk/Flash: Seagate Barracuda 3.5" SATA Hard Drive - 160GB
- Operating System: None
- Accessories: None
- Build and Test: Build & Test: Fanless - Standard (3-5 full business days)
- Power Switch: None - Unit will be set to Auto-Power-On
- Wireless: None
- Dimensions: 31cm X 21.5cm X 5cm

We plan to connect one wireless router directly to the server's Ethernet port. That wireless router will act as a switch & split the internet up to the other 3 wireless routers that will act as access points. The reason we are having 3 access points is so we can cover the entire classroom and some space outside of the classroom. The configuration will be similar to this picture:

We plan to install either DD-WRT or Gargoyle on our WRT54GS's as a custom firmware. We are doing this because the stock firmware on the WRT54GS does not allow more than 30 connections - and 30*3 access points only equals 90 connections. Also, it's not probable that all computers will be connected in equal proportions to each wireless router. DD-WRT and Gargoyle allow you to increase this connection cap. Actually, to be completely honest, we were not able to buy 4 WRT54GS's from Circuit City - there was a max of 3 that we could buy, so we bought 1 WRT54GL from Newegg. They are essentially the same router once we put the custom firmware on.

We also bought 4 50 foot lengths of CAT 6 Ethernet cable from Newegg. Those will connect the three wireless routers to the wireless router we're using as a switch, and attach the wireless router as a switch to the computer.

If you were following all of that really closely, you might have noticed that the motherboard on the server only has 1 network interface - and that since the server is in a mini-ITX configuration & uses the case as a heatsink (no case fan - minimizes dust, is more rugged, etc), one cannot add another network interface as a PCI-E card or something like that. Never fear, for OLPC has thought of this! They are providing us with a USB-to-Ethernet adapter.

One might also think that since there is a 480 megabit theoretical cap on the USB's speed, this could be a problem since it might present a bottleneck, right? Well, since internet will be slow if we even get internet, it won't really be an issue. Especially because the kids using the XO will not have a need for super-speedy Hulu movie streaming, and also because the server does some internet caching using Squid. Exactly how that is administered is a little bit of a mystery to me. I am counting on the fact that OLPC will instruct us in all of this kind of stuff when we have training in Rwanda from June 8th-17th.


We bought 10 1GB USB sticks so we can flash the laptops to the most recent operating system. The operating system, Sugar, was upgraded recently to version 8.2.1, so since they've already been manufactured, they don't have the newest release of Sugar. You can find instructions for flashing (i.e. upgrading) the laptop here. These USB sticks will be used for general purpose storage when they are done upgrading the laptops. They'll probably be given to teachers/Peace Corps Volunteers.

Additional storage is being provided by two Seagate FreeAgent Go 160GB hard drives. One is for us to offload video to (more about that later) and to store pictures, as we plan on taking a lot of both and don't know if we can upload it all to the internet. The other will be either attached to the server and used for extra storage that way, or if that configuration is not possible for backup it will be a communal drive, passed around from XO to XO as a way for kids and teachers to store large files (video projects, stuff like that). That was part of the reason we chose a portable external hard drive - the portable means that it is powered off of the USB port and does not need a separate power supply - which would have required another voltage converter (see section below).

We chose not to buy individual storage for the kids in either USB stick form or SD card form for a couple of reasons. One - cost. No matter how you slice it, a usb stick/sd card is at minimum $4, probably more if you want to order from a reputable

Video/Picture Documentation

A Canon ZR950. We chose this because my dad had one that he wasn't using. It's not the best camera in the world, but it works & records onto miniDV tapes, which are cheap and easy to store. Since we are not sure if we are taking a fully featured laptop, we may not be able to do video editing until we are back in the states & the miniDV tapes will be a huge help. The power supply accepts 100-240 Volts, so all we need is a plug adapter - and I bought lots of extras of those.

A Flip Video Recorder is being generously provided to us by OLPC. We aren't sure which model we're going to get, but since OLPC said that it was going to be HD, and I assume they want to save money, we're probably getting the Flip UltraHD. It's a nice bit of electronics :). When it's full we'll offload it to our portable hard drive, borrowing a laptop for that task from a Peace Corps Volunteer if necessary.

My personal Canon A590. The camera in the link is the A590 IS - I only have the A590, an older model, but they're basically the same. It gets the job done, is pretty sturdy, and runs off of AA batteries, which is a plus because that's one less plug adapter we have to worry about.


We needed voltage converters for the wireless routers since their power supplies were for the US's 110-120 voltage, whereas Mauritania uses the French standard for power - 220 volts and the European 2 prong round pin plugs (Type C).

In addition, though the XO's that we're bringing from the states (the ones that were given to our team) have power supplies that accept all voltages, their plugs have American flat prongs instead of European round prongs. As a result, we need plug adapters.

Other essential power items include extension cords, power strips, and voltage regulators. A voltage regulator protects against surges and spikes in the electricity supply so it won't overload the laptops/server & burn them out. We chose not to buy those in the U.S. because they are heavy and bulky. In addition, it is hard to find European power strips & extension cords in the U.S. They are usually expensive online as well.


Of course, we must bring our laptops with us! OLPC provided all the members of our team with laptops, which was really awesome. So we're obviously bringing them, check out the pictures:

Me with my XO.

The XO - open.

For size comparison, the computer on the left is a 15 inch Macbook Pro. The XO is pretty small! That's Eli in the picture.

We are still debating on whether or not we want to bring a "fully featured" laptop with us. We're not sure, as we know that Peace Corps Volunteers in Tidjikja have laptops, so we can use theirs when we really need to, and bringing a laptop could invite theft. On the other hand, it would be convenient to have the laptop, and if we don't get the visas (a post about our visa situation will be forthcoming, it is not good :( ) & we are stuck in Rwanda, having our own laptop would be incredibly invaluable. It is a definite tradeoff.

As a wrap-up, we bought everything from the links that we posted. They were just about the cheapest prices we could find on the web without going through ebay/craigslist. We decided to buy new for all our supplies because we figure it will have to withstand 5+ years of abuse in the Sahara desert.. so we need equipment at its most durable.

That's all for now!

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