Wifi Connectivity

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This page is part of the XO Support FAQ.     Support Index | Print This Page
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If you want to connect to the internet, and you are using Sugar, see Connecting to the Internet page at the Sugar Labs Wiki.

See also Give Me the Internet, Please for 8.2.0.

Troubleshooting Guide

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

Overview

XO laptops were designed for children in developing nations, where it was faster and less expensive to introduce wireless networks rather than traditional cabled infrastructure. The XO laptop was designed to use these networks, or to connect with other XO laptops using a mesh network or an ad-hoc network.

Setting up a Wireless Network

When setting up a wireless network for XO laptops, configure access points as follows:

  • use a single channel, not "Automatic",
  • it is generally best to choose channels Channels are 1, 6, and 11, to ensure interference between networks is kept to a minimum,
  • if available, 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 laptops must be entered,

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 and adhoc network 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.

If you have a WEP pre-shared key, it can be set within the Terminal Activity:

su -l
/sbin/iwconfig eth0 key 381E966F1EAE4140F83D30C201
exit
  • /sbin/iwconfig sets the WEP key in the XO to match your WAP (of course, substitute your WEP pre-shared key for the 381E966F1EAE4140F83D30C201 in the above example).

WPA Security

WPA security requires extra steps.

The XO is known to be unable to connect to certain Access Points when those networks are configured with WPA security. It is unfortunately not possible to classify such access points without detailed technical diagnosis on a case-by-case basis. See <trac>7825</trac> for the technical details. If you are unable to connect to your WPA access point, you may consider switching to WPA2 (RSN) which is not affected by this flaw.

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

See also