RIT/Wireless networking

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Below are some instructions on establishing wireless networking with the OLPC XO-1 build 803.

Purpose
Learn about the wireless networking tools built into the XO,
Discover the wireless environment in the workroom,
Discover problems with the software or hardware configurations,
Identify known problems and learn the tools for mitigating them,
Propose solutions to those problems (possibly adopt one for a project).
Problem question
WPA/WPA2 encrypted wireless is reported to be unsupported for the XOs at RIT. Are the tools suggested below sufficient to answer this question?
Collectively, report your investigation in a standard laboratory report format at this page. See this page for a discussion of laboratory principles and practices.
Answer the #Problems section questions on your User:Learner/Assignment pages.

References[edit]

Access Point discovery[edit]

  1. Open Terminal
  2. Become the Root user
  3. iwlist scanning

Associate to AP with wpa_supplicant[edit]

  1. Stop NetworkManager and network scripts
  2. service NetworkManager stop 
    service network stop
    
  1. Create a wpa_supplicant config file for your network in /etc/wpa_supplicant.conf. These commands should create a file:
  2. cat <<EOF > /etc/wpa_supplicant.conf 
    ctrl_interface_group=0
    ctrl_interface=/var/run/wpa_supplicant
    eapol_version=1
    ap_scan=1
    fast_reauth=1
    network={ 
            ssid="My SSID" 
            key_mgmt=NONE 
            auth_alg=OPEN 
    }
    <press Ctrl + D here>
    
  1. Or, for WPA/WPA2 with a pre-shared key (psk), substitute these parameters:
  2.        key_mgmt=WPA-PSK
           psk="secret passphrase"
    
  1. Or, to add WPA-EPA (WPA-Enterprise) with identity and password authentication, add these parameters:
  2.        key_mgmt=WPA-EAP
           eap=PEAP
           identity="userid"
           password="foobar"
    
  1. Run wpa_supplicant like this:
  2. /usr/sbin/wpa_supplicant -ddd -ieth0 -c/etc/wpa_supplicant.conf -Dwext
    
    • -ddd is the highest debug level, -B runs the daemon in the background

Configure TCP/IP[edit]

  1. Activate the network Neighborhood view (in a new Terminal):
  2. su -l
    service network start
    ifup eth0
    service NetworkManager start
    
  1. Test your interface

Mesh networking[edit]

  1. Connect to a Mesh networking channel

The abundance of wireless devices on campus can lead to spectrum and digital saturation that degrades the networking service. XOs can collaborate with campus Access Points, so they should disable their Mesh broadcasts to reduce unnecessary traffic. The following command [1] accomplishes this:

echo 0 > /sys/class/net/eth0/lbs_mesh

Should Mesh networking be needed, execute the following command [2]:

echo 1 > /sys/class/net/eth0/lbs_mesh

Problems[edit]

  1. Show evidence of your connection speed on the RIT AP wireless.
  2. Show evidence of connecting to another XO with a Mesh interface.
  3. What are the essential differences of the AP and Mesh networking modes?
  4. *RIT reportedly scans their on campus wireless spectrum and floods any rogue, (ad-hoc?) cells with disconnect packets. Does this actually interfere with the XO's 802.11s (modified) Mesh interface? Explain why or why not. What are the options to enable Mesh networking on campus?
  5. Identify the wireless networking bugs recorded at
    1. http://dev.laptop.org
    2. http://bugs.sugarlabs.org
  6. If you have any significant comments or observations to add to any of these bug reports or a new bug to report, do so and link your comments to your report.
    • See these references for bug reporting, triage guide,
    • Note: Duplicate reports will have negative consequences (identifying duplicates and triaging have positive consequences)
  7. Translate su -l and ifup into full English words.

* optional, advanced question.