Wifi Connectivity: Difference between revisions

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{{G1G1 Support FAQ}}
{{G1G1 Support FAQ}}


If you want to connect to the internet, and you are using Sugar, see [http://wiki.sugarlabs.org/go/Documentation_Team/User_Manual/Connecting_to_the_Internet Connecting to the Internet] page at the Sugar Labs Wiki.
= 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.


See also [http://laptop.org/8.2.0/manual/XO_GiveMeTheInternet.html Give Me the Internet, Please] for 8.2.0.
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 server as [[Mesh Portals]], and further details can be found on [[Mesh_Network_Details#Mesh_Portals|the Mesh Network Details page]].


== Troubleshooting Guide ==
= Getting Started =


The [[Wifi Troubleshooting Guide]] provides a step by step checklist to review prior to contacting [mailto:help@laptop.org Technical Support].
* you must have a Wireless Access Point (WAP) nearby
* verify the network name (SSID) and its password, if it has one
* carefully follow the [http://laptop.org/laptop/start/connecting.shtml Gettting Started instructions]


== Overview ==
= Special Considerations =


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.
== Wireless Access Point Setup ==


== Setting up a Wireless Network ==
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.


When setting up a wireless network for XO laptops, configure access points as follows:
Some key setup considerations for your Wireless Access Point are:


* A single channel should be selected, not "Automatic"
* use a single channel, not "Automatic",
* Preferred [[#Channel|Channels]] are 1, 6, and 11
* it is generally best to choose channels [[#Channel|Channels]] are 1, 6, and 11, to ensure interference between networks is kept to a minimum,
* The wireless network mode should be "Mixed" or "Wireless-G", not "Disabled" or "Other"
* if available, the wireless network mode should be "Mixed" or "Wireless-G", not "Disabled" or "Other",
* If Wireless [[#MAC Filtering|MAC Filtering]] is enabled, the [[ifconfig#MAC Address|MAC address]] for the XO must be entered
* if Wireless [[#MAC Filtering|MAC Filtering]] is enabled, the [[ifconfig#MAC Address|MAC address]] for the XO laptops must be entered,
* The latest Firmware should loaded on your access point
* Make sure that there are only alphanumeric characters and no spaces in your [[#SSID Network Name|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'' 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 ===
=== Channel ===
Line 46: Line 26:
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.
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.
Therefore, the [[mesh networking]] and ad-hoc network between XO laptops is designed to work with channels 1, 6 or 11.


=== Security ===
=== Security ===
====What is the difference between a key and a passphrase?====


Set up the access point for WPA2 security.
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).


Do not use WEP, it is not secure.
So, the passphase is the long password that is relatively easy to remember while the key looks like a random sequence of characters. The lenght 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.


=== MAC Filtering ===
Here is one example, for WEP:
* Key length: 128 bits
* PassPhrase: MyPassPhrase
* Resuting Hex Key (26 characters long): 381E966F1EAE4140F83D30C201
* Converted using: http://www.corecoding.com/utilities/wep2hex.php


Wireless MAC filtering is a security measure that restricts access to the access by MAC address. Every XO has a unique address assigned at the time of manufacture.
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


However, the measure is only effective against naive users, because MAC addresses can be changed.
==== WEP Security ====

WEP Security is built in to the XO.

==== WPA Security ====

WPA security was not initially supported on XO laptops. If you are a knowledgeable Linux user, you can find instructions here to access the Internet with WPA security, by [[WPA Manual Setting|manually setting up WPA]]. It may be best for less experienced users to wait for the next stable XO software release, which should be available by the end of Janurary 2008. If you absolutely need WPA now, you can get it by performing an [[olpc-upgrade|Upgrade]] to version 653, but in the process you may lose all data on your laptop.

=====Can I calculate a WPA key using an XO?=====

Note that WPA is not currently supported (as of build 650, Dec. 2007), but yes, you can.

1. Start the "Terminal" activity from the Frame; instructions can be found [[#How do I access a Linux command prompt|here.]] You may have to scroll the icons along the bottom of the Frame to the right (by clicking on the [[Image:Frame-scroll-right.gif|25px]] button at the right of the Activities taskbar) to find the [[Image:Activity-terminal.svg|35px]] icon; it is labeled "Terminal".

2. Type the following, substituting the values for ssid and passphrase (and then press the "Enter" key):

/usr/sbin/wpa_passphrase <ssid> <passphrase>

3. The key will be displayed in the line starting with "psk=".

If you plan to use the same WPA key frequently, there is a script available at [[WPA Manual Setting]] with discussion [[Talk:Support_FAQ#Apple_Access_Point_Connection|here]] and [[Talk:WPA_Manual_Setting|here]]


==== MAC Filtering ====

Wireless [[#MAC Filtering|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 [[ifconfig#MAC Address|MAC address]] for the XO is displayed using the [[Linux]] command [[ifconfig]].
The [[ifconfig#MAC Address|MAC address]] for the XO is displayed using the [[Linux]] command [[ifconfig]].


=== Specific WAP Notes ===
== See also ==


* [[Hidden]] networks,
A complete matrix of [[Wireless Access Point Compatibility]] is being updated by the support community.
* [[Manual Wireless Association]]
* [[Wireless Access Point Compatibility]]


[[Category:Network]]
====Apple Airport====

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

# Go to: http://www.corecoding.com/utilities/wep2hex.php and convert your password into a hex phrase.
# Click on the Access Point in the [[neighborhood view]].
# Choose Hex input for the key; and choose "shared" key instead of "open".
# Enter your hex phrase.
# 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 [[Support_FAQ#How_do_I_update.2Fupgrade_my_laptop.3F|upgrade to build 653]].

====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:

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

====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 - 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.

== XO Setup ==

=== network.cfg ===

The '''network.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.

*Launch the [[Terminal Activity]] 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. There is an [http://dev.laptop.org/ticket/2910 outstanding bug (#2910)] on this.

= Troubleshooting Guide =

The [[Wifi Troubleshooting Guide]] provides a step by step checklist to review prior to contacting [mailto:help@laptop.org Technical Support].

Latest revision as of 01:26, 28 June 2014

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.

Therefore, the mesh networking and ad-hoc network between XO laptops is designed to work with channels 1, 6 or 11.

Security

Set up the access point for WPA2 security.

Do not use WEP, it is not secure.

MAC Filtering

Wireless MAC filtering is a security measure that restricts access to the access by MAC address. Every XO has a unique address assigned at the time of manufacture.

However, the measure is only effective against naive users, because MAC addresses can be changed.

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

See also

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