Wifi Connectivity

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This page is part of the XO Support FAQ.     Support Index | Print This Page
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Overview

XO laptops were intentionally designed for children in developing nations, where it is faster and less expensive to introduce wireless connections, rather than a traditional telecom infrastructure. The XO Laptop is primarily designed to network with other XO Laptops using a mesh network, but the XO is also wifi capable for direct internet connection.

At the moment, an XO laptop cannot be on both the Internet and on the mesh network at the same time with a default laptop configuration. This ability will hopefully be re-enabled by default in the future; until then, School Servers can serve as Mesh Portals, and further details can be found on the Mesh Network Details page.

Getting Started

  • you must have a Wireless Access Point (WAP) nearby
  • verify the network name (SSID) and its password, if it has one
  • carefully follow the Getting Started instructions

Special Considerations

Wireless Access Point Setup

The OLPC Support Team has been gathering notes and configuration tips for various Wireless Access Point (WAP) connectivity. We are actively working to resolve minor compatibility issues with various Wireless Access points.

Some key setup considerations for your Wireless Access Point are:

  • A single channel should be selected, not "Automatic"
  • Preferred Channels are 1, 6, and 11
  • The wireless network mode should be "Mixed" or "Wireless-G", not "Disabled" or "Other"
  • If Wireless MAC Filtering is enabled, the MAC address for the XO must be entered
  • The latest Firmware should be loaded on your access point
  • Make sure that there are only alphanumeric characters and no spaces in your WAP's SSID

SSID Network Name

When in the Neighborhood View, your Wifi SSID should be visible when you hover over the hotspot dot.

If you have a hidden SSID, your hotspot dot will not be visible. The network can be manually added using the iwconfig command through the Terminal Activity: 

su -l
/sbin/iwconfig eth0 mode managed essid <myhiddennetwork>
/sbin/dhclient eth0
exit
  • su -l creates a root process;
  • iwconfig connects to your hidden network (of course, substitute the name of your access point for the <myhiddennetwork> in the above example);
  • dhclient will ask for an IP address from the access point.

Channel

With 802.11b or 802.11g, use channel 1, 6 or 11 in the US or Canada. Use of any other channels will degrade your own wireless signal and that of others.

Similarly, the mesh networking between XO laptops is restricted to work only on channels 1, 6 or 11.

Security

What is the difference between a key and a passphrase?

When you try to connect to a secured (encrypted) network your XO has to send an encryption key to the access point. This key is derived from the passphrase you chose when you configured your access point (and also from the ESSID, if you are using WPA).

So, the passphase is the long password that is relatively easy to remember while the key looks like a random sequence of characters. The length of the key varies depending on the type of security and it is usually represented in its Hex form, meaning that it will be formed by a sequence of digits and letters from A to F.

With WEP, the conversion from passphrase to key is not standardized and therefore is different on various companies' access points. Also, the WEP example below is only for 104/128 bit WEP. It will not work on 40/56 bit WEP. For these and other reasons, use WPA if you can.

Here is one example, for WEP:

Here is another example, for WPA-PSK:

  • Key length: 256 bits
  • PassPhrase: MyPassPhrase
  • ESSID: MyEssid
  • Resulting key (64 characters long): c3044f3fbd077e236d12f0b1f9d7761e0e6de266783d843d76edf1da3131bff6
  • Converted using: http://www.xs4all.nl/~rjoris/wpapsk.html

WEP Security

WEP Security is built in to the XO.

WPA Security

WPA security requires extra steps.

MAC Filtering

Wireless MAC Filtering is a security measure that restricts access to the WAP by MAC Address. Every computer or other peripheral has a unique HEX address assigned at the time of manufacture.

The MAC address for the XO is displayed using the Linux command ifconfig.

Note: You will find ifconfig in the /sbin directory, which is not in the default path. Type /sbin/ifconfig

Specific WAP Notes

A matrix of Wireless Access Point Compatibility is being updated by the support community.

Actiontec

Various issues have been reported with Actiontec WAPs. Most seem to resolve after a firmware upgrade of the WAP, and following the setup instructions.

Apple Airport

There are two kinds of Apple Access points: WEP and WPA.

If you have WEP:

  1. Go to: http://www.corecoding.com/utilities/wep2hex.php and convert your password into a hex phrase.
  2. Click on the Access Point in the neighborhood view Mesh key f1 small.png.
  3. Choose Hex input for the key; and choose "shared" key instead of "open".
  4. Enter your hex phrase.
  5. You should be able to associate to and authenticate a connection to an Apple Access point.

If you have WPA, you should note that WPA is not working from the User Interface in build 650. You should upgrade to build 653.

  1. To Find your WPA password, follow Apple's Getting an equivalent network password instructions.
  2. Click on the Access Point in the neighborhood view Mesh key f1 small.png.
  3. Enter Hex input, TKA

Verizon FIOS

The XO cannot see the wireless access point reliably and cannot connect to ActionTec M1424WR unless the router must be set up to use one channel exclusively (1-11) rather than rotate the channel selection

From a computer other than your XO:

  1. Go to your Browser, and type in 192.168.1.1
  2. Screen will open, and you will need to insert "User Name" and "Password." The Default response would be admin / password
  3. New screen will open. Along the top you will spot "Wireless Settings." Select that category.
  4. Along the left side you will see a column. Choose 'Basic Security Settings."
  5. Look for Section.....3. Channel: ______________ If it says "Automatic." it is rotating through eleven channels. Choose just one channel, preferably 1, 6, or 11.
  6. Click the "Apply" button.


Here's another option THAT WORKS to connect to Verizon WEP by:CareBearOne 1 - from the "Terminal Activity" window...type su to get into superuser mode. 2 - type /sbin/iwconfig eth0 key <your WEP key not the passphrase> 3 - type /sbin/iwconfig <--to see the current wireless configuration. 4 - type /sbin/ifconfig <--to see the current ethernet configuration. 5 - type /sbin/dhclient eth0 <--to run the dchp script so your laptop will be assigned an IP address. 6 - type /sbin/ifconfig <--to see the ip address your laptop has been assigned.

Now I need to figure out how to put this in a script!!!!!! Anyone know??

Belkin Pre-N

Some access points that have reported intermittent problems with XOs:

  • BelkinPreN - XO Connects but all other systems disconnect

If you have one of these access points, please contact technical support if none of the basic setup fixes solves your connection problem.

Linksys WRT54GX2

Some access points that have reported intermittent problems with XOs:

  • Linksys WRT54GX2 [and WRT54GX4] - XO Connects but cannot access internet

If you have one of these access points, please contact technical support if none of the basic setup fixes solves your connection problem.

Debug Notes

If you have attempted to connect to a password secured WPA or WEP access point and were unsuccessful, or if you have changed your Access Point settings, then you may need to remove the 'networks.cfg' file, which has saved your password and continues to try the old password (see below).


Remove 'networks.cfg' file

From a Virtual Terminal (click on Ctl-Alt-neighborhood) or from within the Terminal activity type:
rm /home/olpc/.sugar/default/nm/networks.cfg

XO Setup

networks.cfg

The networks.cfg file contains information about the current network configuration from session to session.

If you want to remove any "memory" of connecting to a particular access point or if you change the configuration of your Access Point (such as adding or removing security features), then you will need to remove this file in order to get your XO to connect to the Access Point.

  • to see which networks are currently in your known networks file type:
 more /home/olpc/.sugar/default/nm/networks.cfg            (press "Enter")
  • to delete the network manager config file by typing:
rm /home/olpc/.sugar/default/nm/networks.cfg    (press "Enter")

Restart your XO laptop, or restart Sugar by pressing the Ctrl+Alt+Erase keys at the same time; your laptop will NOT automatically try to connect to the "known" access point.

Proxy Settings

The initial software build on the Give1Get1 shipped in December 2007 (Build 650) does not support a user interface to change the web browser by proxy settings. You can change your preferences by creating a user.js file in /home/olpc/.sugar/default/gecko - the browsers profile folder.

The file should look like this: 

pref("network.proxy.http",  "<set to your proxy server>");
pref("network.proxy.http_port",  <set to 8080 or the appropriate port>);
pref("network.proxy.type",1);

or you can use the autoconfig: 

pref("network.proxy.autoconfig_url", "<your proxy>");

On more recent builds, to change your browser's proxy settings: enter "about:config" into the browser's url field. This will load the configuration page for the browser. There are three settings you must change to work with a proxy: 

network.proxy.http       <set to your proxy server>
network.proxy.http_port  <set to 8080 or the appropriate port>
network.proxy.type       <change to 1>

To change a setting, double-click on a line and type the new setting into the new window that pops up.


How to Connect to the Virtual Mesh

  1. Go to the terminal window.
  2. sugar-control-panel -g jabber (hint: type sugar-co then hit tab to complete the command)
    • will display your current setting.
  3. sugar-control-panel -s jabber xochat.org
    • will change to the public server.
    • Currently the xochat.org jabber server is offline with no known time frame to return to online status.
  4. Reboot Sugar with CTRL-ALT-ERASE (CTRL-ALT-BACKSPACE in an emulator session)

Troubleshooting Guide

The Wifi Troubleshooting Guide provides a step by step checklist to review prior to contacting Technical Support.

See also

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