Collab Network School Wifi Tests

In these collaboration and networking tests, the laptops are connected to a School server through normal 802.11b/g access points. In general, the laptops are registered with the school server and using the school's presence service.

Other networking modes tested are simple mesh, simple wifi and school mesh.

Presence

Test 0408B

Laptop Build: 703

School Server Build: 160

School Server Channels: Zoom Model 4400 "AP+2" on channel 1

This test was a staged startup of 38 laptops. Ten of the laptops had previously been associated with the school WiFi AP, the rest needed to be manually connected. Around 28 of the laptops had been previously registered with the school server (in Test 0331G). In the end, all 38 laptops were able to associate with the access point and register with the server.

First, twenty laptops (X50 - X59, X62 - X71) were turned on simultaneously. All ten machines previously using that access point associated with it again. All of the new machines were manually associated with the school AP, then registered. All registered successfully on the first try.

Once a laptop was registered for the first time, Sugar was restarted.

Eight more laptops (X72 - X79) were turned on, followed by 10 more (X20 - X29). All were manually associated with the school AP and registered. There were problems registering some of the laptops (e.g. X25). We discovered that if an attempt to register the laptop was made on a network without a school server, Sugar would silently refuse to perform another registration attempt until restarted (Trac 6857). Once we realized what the problem was, we were able to register all laptops on the first try.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1(a), Chan 1(b), Chan 1(c)

Laptop X25 logs: All, info, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list

Test 0408F

Laptop Build: 703

School Server Build: 160

School Server Channels: Zoom Model 4400 "AP+2" on channel 1

This test was a fast startup of 77 laptops. All of the laptops had previously been associated with the school WiFi AP, and previously registered with the school server (in Test 0408B and Test 0408C). In the end, all but six of the laptops were able to associate with the access point. Due to timing of the test, we are unsure how many successfully joined Gable.

Seventy seven laptops (X00 - X39, X50 - X59, X62 - X79, X90 - X98) were turned on sequentially, roughly four laptops per second.

One of the laptops (X31) did not even start a simple mesh (Trac 5848).

Five other laptops (X00 neé X100, X04, X15, X18, and X23) did not re-associate with the school AP, and created a simple mesh instead.

As this test was conducted immediately after Test 0408C, the school presence service was maintaining state and made it impossible to determine which laptops were properly connected using Gabble.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1(a), Chan 1(b), Chan 1(c)

Laptop X31 logs: All, info, /var/log/messages, Telepathy/Sugar

Laptop X23 logs: All, info, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list

Test 0331G

Laptop Build: 703

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: Linksys WiFi AP on channel 1

This test was a simultaneous startup of 28 unregistered laptop. It was sheer chaos! Laptops had problems associating with the access point and registering with the school server. Many of the laptops took multiple tries to associate with the "linksys" network, and multiple tries to register with the school server.

All laptops (X50 - X59, X62 - X79) were turned on simultaneously. Once booted, it frequently took several attempts to overrule the pre-programmed school server search algorithm by clicking on the "linksys" network in the neighborhood view. Some laptops (X73, X74, X54) proved particularly difficult, and were turned off (once logs were copied).

Once the laptops were connected with the "linksys" network, they were registered. Unlike previous experiments with registration, it frequently took a number of tries to register a laptop.

Once a laptop was registered, Sugar was restarted.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Chan 1(a), Chan 1(b), Chan 1(c)

Laptop X54 logs: All, /var/log/messages, Telepathy/Sugar

Laptop X74 logs: All, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list

Test 0323J

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: Linksys WiFi AP on channel 1

This test was a simultaneous startup of 37 laptops. It was determined that the AP only supported up to thirty simultaneous connections. Other laptops were unable to connect to the school server.

Thirty-seven laptops (X50 - X59, X62 - X79, X90 - X98) were turned on sequentially, with around one sec between each one. All laptops had previously been registered with the school server. All laptops started a simple mesh. Manually, they each were instructed to use the linksys access point by clicking on its circle (icon) in the neighborhood view.

The first thirty laptops connected to the school server, and displayed presence information about all the other connected laptops. The remaining seven laptops (X54, X59, X64, X75, X90, X91, and X98) were unable to associate with the AP.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Due to operator error, we do not have packet traces for this test (I forgot to change mode of sniffing interfaces, and associate them with Access Point. Even though they were monitoring the correct channel they did not capture any traffic). Chan 1 (a), Chan 1 (b), Chan 1 (c)

Server logs: /var/log/messages, laptop list

Test 0323K

Laptop Build: 699 + telepathy-salut-0.2.3-1.olpc2.i386.rpm

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: Linksys WiFi AP on channel 1

This test was a simultaneous startup of 30 laptops, previously connected to a school server through an AP. None of the laptops tried to connect with the previous AP. 29 of them formed a simple mesh, with one deciding not to talk to anybody.

Thirty laptops (X50 - X53, X55 - X58, X62 - X63, X65 - X74, X76 - X79, X92 - X97) were turned on sequentially, with around one sec between each one. All laptops had previously been registered with the school server, and had used this AP the last time they were powered on.

All laptops started a simple mesh, except for X55, which didn't show any network connection (Trac 5848).

I was surprised. I thought the default behavior was to associate with the previous network, if found! Logged as Trac ticket 6811.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1.

Packet Traces: Due to operator error, we do not have packet traces for this test (forgot to change mode of sniffing interfaces, and associate them with Access Point. Even though they were monitoring the correct channel they did not capture any traffic. Chan 1 (a), Chan 1 (b), Chan 1 (c)

Laptop X55 logs: All, dmesg, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list

Write

Test 0331H

Laptop Build: 703 + Write 55

School Server Build: 160 + 22.p6 Libertas firmware

School Server Channels: Linksys WiFi AP on channel 1

This test started with 24 laptops which supposedly were connected to a School server through a WiFi access point. After noticing differences in laptops' neighborhood views, Sugar was restarted on all laptops. Finally, a Write activity was shared, but nobody saw it.

This test started after a previous experiment in registration. All the laptops had been registered, but they weren't properly communicating with the school presence service. After noticing a number of laptops with 10, 12, 14, etc..., neighbors shown, I checked the ejabberd online users page (http://172.18.0.1:5280/admin) and only saw around ten laptops. I restarted Sugar again on all the laptops, and finally saw 24 laptops online with ejabberd.

X53 was a laptop which still showed only two laptops, after restarting Sugar.

The Write activity was started on laptop X69. The activity was shared with the neighborhood. No other laptop saw the shared activity.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1. The logs are divided up into two parts, part 1 and part 2.

Packet Traces: Chan 1(a) pt1, Chan 1(a) pt2, Chan 1(b) pt1, Chan 1(b) pt2, Chan 1(c) pt1, Chan 1(c) pt2

Laptop X53 logs: All, /var/log/messages, Telepathy/Sugar

Laptop X69 logs: All, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list

Chat

Test 0408C

Laptop Build: 703

School Server Build: 160

School Server Channels: Zoom Model 4400 "AP+2" on channel 1

This test was a test of Chat, starting with 38 laptops, while adding another 40 laptops to the network. By the end of the test, 78 laptops were associated with the mesh, and 75 laptops were successfully chatting.

Thirty-eight laptops were started and associated with the school AP in a previous test. Chat was started on X62, and shared with the neighborhood. All associated laptops immediately saw the shared activity.

An additional twenty laptops were turned on and associated with the school AP, registered with the server, and Sugar restarted. These laptops then joined the Chat.

An additional seventeen laptops were turned on and associated with the school AP, registered with the server, and Sugar restarted. These laptops then joined the Chat.

Some of the laptops (e.g. X97, X13) had problems registering with the school server, but in case it was determined to be the problem now known as Trac 6857.

The logging was conducted with three Active Antennas, separated by one meter, all on channel 1. This test took a while to performs, so the packet trace was stopped and restarted.

Packet Traces: Chan 1(a), Chan 1(b), Chan 1(c) (later) Chan 1(a), Chan 1(b), Chan 1(c) (even later) Chan 1(a), Chan 1(b), Chan 1(c)

Packet Traces: Chan 1(a), Chan 1(b), Chan 1(c)

Laptop X97 logs: All, info, /var/log/messages, Telepathy/Sugar

Laptop X13 logs: All, info, /var/log/messages, Telepathy/Sugar

Server logs: /var/log/messages, laptop list