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diff --git a/doc/kwifimanager/index.docbook b/doc/kwifimanager/index.docbook new file mode 100644 index 00000000..07cc908d --- /dev/null +++ b/doc/kwifimanager/index.docbook @@ -0,0 +1,549 @@ +<?xml version="1.0" ?> +<!DOCTYPE book PUBLIC "-//KDE//DTD DocBook XML V4.2-Based Variant V1.1//EN" "dtd/kdex.dtd" [ + <!ENTITY kwifimanager "<application>KWiFiManager</application>"> + <!ENTITY LAN "<acronym>LAN</acronym>"> + <!ENTITY kappname "&kwifimanager;"> + <!ENTITY package "kdenetwork"> + <!ENTITY % English "INCLUDE"> <!-- change language only here --> + <!ENTITY % addindex "IGNORE"> +]> +<book lang="&language;"> + <bookinfo> + <title>The &kwifimanager; Handbook</title> + <authorgroup> + <author> + <firstname>Stefan</firstname> + <surname>Winter</surname> + <affiliation> + <address> + <email>swinter@kde.org</email> + </address> + </affiliation> + </author> + <!-- TRANS:ROLES_OF_TRANSLATORS --> + </authorgroup> + <legalnotice>&FDLNotice;</legalnotice> + <copyright> + <year>2002-05</year> + <holder>Stefan Winter</holder> + </copyright> + <date>2005--05-11</date> + <releaseinfo>3.5.0</releaseinfo> + <abstract> + <para>The &kwifimanager; suite can be used to configure and monitor wireless &LAN; + cards. It consists of a stand-alone application and a module for the &kde; Control + Center.</para> + </abstract> + <keywordset> + <keyword>KDE</keyword> + <keyword>wireless</keyword> + <keyword>Wi-Fi</keyword> + <keyword>wlan</keyword> + <keyword>WEP</keyword> + <keyword>wlan-ng</keyword> + </keywordset> + </bookinfo> + <chapter id="introduction"> + <title>Introduction</title> + <para> The &kwifimanager; suite is a set of tools which allows you to manage your wireless + &LAN; Network Interface card (PC-Card, PCI or miniPCI) under the K Desktop Environment. It + provides information about your current connection and lets you set up up to ten independent + configurations and use up to four configrations that are pre-configured by distribution-specific + scripts. If you are in a place where none of your preconfigured networks is available, + you can also dynamically switch to an available network with almost no configuration effort. + &kwifimanager; supports every wireless &LAN; card that uses the wireless extensions + interface. This includes virtually all wireless &LAN; cards that are operational at all + under the &Linux; operating system.</para> + </chapter> + <chapter id="using"> + <title>Using the &kwifimanager; suite</title> + <sect1 id="kwifimanager-application"> + <title>The &kwifimanager; application</title> + <para> Purpose of the main &kwifimanager; application is to show the currently active + network configuration and to display connection quality and access points.</para> + <para>The main application is launched by either typing<userinput>kwifimanager</userinput> at + the command prompt of a console window or via the K Menu, where it is located by default in + the<guisubmenu>Applications</guisubmenu> group. If &kwifimanager; is already running + but minimised to the system tray then it can be restored by clicking once on the <link + linkend="systrayicon">system tray icon</link>. If there is more than one wireless &LAN; + card in your system, just open more than one instance of &kwifimanager;: every instance + will show information about a different card automatically. + The &GUI; elements of the application + are explained in the following subsections.</para> + <sect2 id="kwifimanager-main"> + <title>Main window</title> + <para> The &kwifimanager; main window consists of five parts:</para> + <sect3 id="signalquality"> + <title>Signal quality display</title> + <para> Here you can see the quality and type of the active connection. The uppermost icon + displays the general state of the wireless network via a set of pictograms:<itemizedlist> + <listitem> + <para> a wireless &LAN; card with a question tag means that no card was detected + or its state could not be determined</para> + </listitem> + <listitem> + <para> a single laptop means that a wireless &LAN; card is inserted and in + Infrastructure mode, but there is no radio signal from access-points. The card is + out of range and can not communicate to the infrastructure network.</para> + </listitem> + <listitem> + <para> a laptop that is connected to an access point means that a connection to an + access point is established.</para> + </listitem> + <listitem> + <para> two laptops mean that your system is in Ad-Hoc mode without access points. It + may or may not have established a Peer-to-Peer connection.</para> + </listitem> + </itemizedlist> + </para> + <para> Below these pictograms is a small quality meter. It displays, in a cellular-like + manner, the quality level of the current connection. This information is only available + in Infrastructure mode. In Ad-Hoc mode, the level is always 0.</para> + <para> This graphical information is supplemented by an integer value below the icon. It + shows the signal quality, and is computed in one of two ways: <itemizedlist> + <listitem> + <para>a directly reported value from the card if the card supports + <quote>Quality</quote> reporting</para> + </listitem> + <listitem> + <para> + <literal>(signal strength in dBm) - (noise level in dBm)</literal> for cards that + do not support that.</para> + </listitem> + </itemizedlist> You can manually change the method used by turning + <guimenu>File</guimenu>, <guimenuitem>Use alternate strength calculation</guimenuitem> + on or off. Turning the option on means to use the second method. If your card is out of + range, the value is 0; if no card is inserted or your card is in Ad-Hoc mode it will + show N/A.</para> + </sect3> + <sect3 id="speed"> + <title>Connection speed</title> + <para> An indicator for the current connection speed is shown at the right-hand side of + the main window above the configuration info. If the speed settings are set to AUTO, the + value will change once in a while as the card adjusts the connection speed according to + the signal quality. The scale of the bar graph will automatically adjust to up to 108 + MBit/s when the current connection speed exceeds 11 MBit/s.</para> + </sect3> + <sect3 id="current-config"> + <title>Current configuration</title> + <para>Here you can find information about your card configuration. It displays the + following information:</para> + <itemizedlist> + <listitem> + <para> the network with which the card is connected to / tries to connect to + (<guilabel>Searching for network:</guilabel> or <guilabel>Connected to + network:</guilabel>)</para> + </listitem> + <listitem> + <para> the <acronym>MAC</acronym> address of the access point to which the card is + connected.</para> + <para> If the card is in Infrastructure mode but out of range, an appropriate warning + (<computeroutput>- no access point -</computeroutput>) is displayed to indicate + that no connection is established.</para> + <para> In Ad-Hoc mode, the field shows an address that is associated with one of the + cards in the Ad-Hoc network. It displays a MAC address that has a non-global scope: + its second bit is set to 1, which often results in a prefix of <quote>02:</quote> + instead of <quote>00:</quote>. Many people think this is an error, but in fact it is + done on purpose to show that the cell you are connected to is not an actual physical + device, but rather an imaginary access point without a real physical address.</para> + <informalexample> + <para> Your card is the first card that enters Ad-Hoc mode with a given SSID. Then all other cards + entering Ad-Hoc mode with the same SSID will see your MAC-address, slightly modified: instead + of<computeroutput>00:xx:yy:zz:aa:bb</computeroutput> it will + show<computeroutput>02:xx:yy:zz:aa:bb</computeroutput>. This behavior is + intentional.</para> + </informalexample> + </listitem> + <listitem> + <para> on most cards (those that have the capability to report it), the frequency on + which the card is transmitting data and the corresponding channel number is + displayed.</para> + </listitem> + <listitem> + <para> your local IP (version 4) address, if available. If no address could be + retrieved from the networking subsystem, the word <guilabel>unavailable</guilabel> + is displayed.</para> + </listitem> + <listitem> + <para> encryption status (only if you have started &kwifimanager; as<systemitem + class="username">root</systemitem>). The display will only show + <guilabel>off</guilabel> or <guilabel>active</guilabel>, but never the real key. + This is intentional in order to not reveal the <acronym>WEP</acronym> key to people + passing by the users screen.</para> + </listitem> + </itemizedlist> + </sect3> + <sect3 id="ap-info"> + <title>Access Point information (bottom area)</title> + <para> The last line of the main window shows information about your AccessPoint. This + requires that your system administrator provided a list of MAC addresses with a + corresponding information. An example for such a list can be found + in<filename>$<envar>KDEDIR</envar>/share/apps/kwifimanager/locations/DE_BW_Karlsruhe_University.loc</filename> + </para> + <para>If you want to set up a new list, simply create a file in the same format and copy + it into the folder <filename class="directory" + >$<envar>KDEDIR</envar>/share/apps/kwifimanager/locations/</filename> + </para> + <para>It will be automatically parsed at the next start of &kwifimanager;. If you have + a list and want to have it included in future releases of &kwifimanager;, simply + send it to the author or current maintainer.</para> + </sect3> + <sect3 id="scanning"> + <title>Information about available networks</title> + <para> The lower-left area of the main window contains a button named <guibutton>Scan for + networks...</guibutton>. If you click on this button, &kwifimanager; will attempt + to retrieve a list of all networks that are in range of your card. The outcome of this + scan depends on two factors: <itemizedlist> + <listitem> + <para>the overall ability of your card and driver to perform network scans</para> + </listitem> + <listitem> + <para>if you have root permissions or not</para> + </listitem> + </itemizedlist> If your card or driver arent able to scan the network, your scanning + results will always be empty. If you are not the root user, the list may be incomplete + or outdated. </para> + <para> In order to receive a reliable, current list of access points you will need to + start the scan with root privileges, for example by using the &kdesu; utility to + start &kwifimanager;</para> + <para> If at least one network was found, you are presented with a table showing details + of the network. It has four columns that inform you about <itemizedlist> + <listitem> + <para>the network name (or the string <guilabel>(hidden cell)</guilabel> if the name + is not disclosed by the access point during the scan)</para> + </listitem> + <listitem> + <para>the type (whether is a <guilabel>Managed</guilabel> or an + <guilabel>Ad-Hoc</guilabel> network)</para> + </listitem> + <listitem> + <para>the signal strength of the network</para> + </listitem> + <listitem> + <para>and whether or not <acronym>WEP</acronym> encryption is used</para> + </listitem> + </itemizedlist> In case of an active <acronym>WEP</acronym> encryption, you can click on + that column and enter the network key. &kwifimanager; will automatically try to + guess if the key is a hexadecimal number or a string. </para> + <para> If the network information for the highlighted network is complete (&ie; all + columns contain meaningful information), you can use the button <guibutton>Switch to + network</guibutton> to enter the selected network. If &kwifimanager; has no root + privileges, you will be prompted with a password prompt to enter the root password in + order to change the network. </para> + <para> Clicking on <guibutton>Close</guibutton> dismisses the network information screen + without changes to the existing settings. </para> + </sect3> + </sect2> + <sect2 id="statistics"> + <title>Statistics Viewer</title> + <para> Optionally, by selecting <guimenuitem>Connection statistics</guimenuitem> in the + <guimenu>File</guimenu> menu, a separate window can be shown which displays the signal + level and noise level graphs of the last 240 seconds. The signal level is displayed in + blue and the noise level in red. The difference (SIGNAL minus NOISE) is the connection + quality which is displayed in the main window.</para> + <para>Some cards do not report meaningful noise information. If this is the case for your + card and you get annoyed by the irrelevant red line, you can disable showing the noise + level in the statistics window by unselecting <menuchoice> + <guimenu> Config </guimenu> + <guimenuitem> Show noise level in statistics </guimenuitem> + </menuchoice> in the &kwifimanager; main window.</para> + </sect2> + <sect2 id="config-edit"> + <title>Configuration Editor</title> + <para> By selecting<menuchoice> + <guimenu>Config</guimenu> + <guimenuitem>Configuration Editor</guimenuitem> + </menuchoice> you are taken to the <link linkend="control-center">control center + module</link> of &kwifimanager;. In case you are not the <systemitem class="username" + >root</systemitem> user, a window will pop up requesting the <systemitem + class="username">root</systemitem> password. This is because the configuration module + allows you to change network connectivity und uses <userinput>ifconfig</userinput> to make + changes, which requires root privileges.</para> + </sect2> + <sect2 id="misc"> + <title>Miscellaneous</title> + <para>There are some minor additional features worth of being mentioned.</para> + <sect3 id="acoustic-scanning"> + <title>Acoustic Scanning</title> + <para>First, there is a feature named <guilabel>Acoustic Scanning</guilabel>. If this + option is enabled, the connection quality is converted into an acoustic signal. A higher + signal quality leads to a higher frequency of the <quote>beep</quote> output and to a + more rapid beeping. If you've ever seen the Star Trek(tm) series you will see some + parallels to their <quote>tricorders</quote> + </para> + </sect3> + <sect3 id="logging"> + <title>Network logging</title> + <para>A second feature is network logging. It just means that &kwifimanager; will log + the name of the network you are connecting to every time your network changes. + This option is most useful when searching for the special network name + <quote>any</quote>. In this mode, the card will log into any network it finds. The + logfile's position is <filename class="directory" + >$<envar>HOME</envar>/.kde/share/apps/kwifimanager/wireless-log</filename> + </para> + </sect3> + <sect3> + <title>Disabling the wireless network</title> + <para>You can completely disable the card by selecting the option <guimenu>File</guimenu> + <guimenuitem>Disable radio</guimenuitem>. Using this option will turn off the cards + transmitter which effectively turns it off and saves a little bit of energy. This will + only work for your card if it accepts changes to its + <computeroutput>txpower</computeroutput> property.</para> + </sect3> + </sect2> + </sect1> + <sect1 id="systrayicon"> + <title>The system tray icon</title> + <para>When &kwifimanager; is launched, it installs a small icon in the system tray. The icon contains + parts of the information of the main window, namely the bar graph and optionally the signal strength + number. If you hover over the icon with the mouse for a few seconds, a tooltip will appear that + contains the currently connected network name. Whether or not the strength number shall be + shown can be configured via <guimenu>Config</guimenu>, + <guimenuitem>Show Strength Number in System Tray</guimenuitem>.</para> + <para>If you have configured &kwifimanager; to stay in the system tray when clicking on the + <guibutton>X</guibutton> button, the icon will stay in the tray persistently unless you really exit + the application by clicking on <guimenu>File</guimenu>, <guimenuitem>Quit</guimenuitem>.</para> + <para>You can always hide the main application to the system tray by clicking on the tray icon. Similarly, + to restore the main application from the tray, just click on it once.</para> + </sect1> + <sect1 id="control-center"> + <title>The Control Center module</title> + <para>The configuration module in the &kcontrolcenter; is perhaps the most useful part of + the &kwifimanager; suite. Here you can actually change the basic settings of your + wireless &LAN; card. The module can manage up to ten independent configurations for the + card. If you dont need that many configurations, you can reduce the number of configs + shown at any time by changing the <guilabel>Number of Configurations</guilabel> entry. + If you have configured your wireless settings with a distribution-specific tool, chances are good + that the &kcontrolcenter; module will automatically detect this and also read in and show that + configuration. In any case these configurations will be read-only, because it is the distribution's + job to handle updating these settings and the module should not interfere with their internal magic. + Up to five additional preset configurations can be shown in addition to the ten + that are self-definable. These configurations will have the name <guilabel>Vendor x</guilabel> + to distinguish them from the others. + The &kcontrolcenter; can even automatically set your card up whenever you start the module. + Since establishing (or bringing down) a network connection is a security sensitive operation, + any changes to the configuration can only be done by <systemitem class="username">root</systemitem>.</para> + <sect2 id="configuration-tab"> + <title>The Configuration Tabs</title> + <para>The configurations are split up in three parts: <itemizedlist> + <listitem> + <para>general configuration settings (like the network name)</para> + </listitem> + <listitem> + <para>encryption settings</para> + </listitem> + <listitem> + <para>power saving settings</para> + </listitem> + </itemizedlist> + These parts are explained in the following sections. + </para> + <sect3 id="config_general"> + <title>General settings</title> + <para>The upper part of the control center module consists of one to ten tabs labelled + <guilabel>Config 1</guilabel> through <guilabel>Config 10</guilabel>. Each of these tabs + can hold a configuration for your WLAN card. In addition (as explained above) up to five vendor-specific + configurations may be visible, labelled <guilabel>Vendor 1</guilabel> through <guilabel>Vendor 5</guilabel>.</para> + <para>The most important settings are always visible, the cryptography and power management + options are only shown when activated. The perhaps most important element in each + configuration tab is the field<guilabel>Network name</guilabel>. Here you can specify + which network you would like to log into. You can either specify the name of your network + directly, or you can try a scan on all available networks by setting the network name to + <userinput>any</userinput>.</para> + <para>In addition to the network name, you have to specify the type of network to log into. + That's the purpose of the button group<guilabel>Operation mode</guilabel>. The + option<guilabel>Managed</guilabel> means that the network consists of designated + base stations, so-called <quote>access points</quote> or sometimes <quote>residential + gateways</quote>. This is the most common operation mode for company networks. The second + option,<guilabel>Ad-hoc</guilabel> means that your network is just a direct + connection between computers, without access points. The three other options + (<guilabel>Repeater</guilabel>, <guilabel>Master</guilabel> and <guilabel>Secondary</guilabel>) + are only very seldomly used. If you want to use them, please be aware that these settings are simply + passed to the iwconfig program and have not been tested extensively. In case something doesnt + work as expected, you are welcome to send a bug report.</para> + <para>You can optionally set the connection speed for your connection. The setting + <guilabel>auto</guilabel> should do for most uses, since the card will determine the + appropriate speed itself. However, if you find that the speed changes every few seconds, + for example when you have a weak connection, you can set the speed manually.</para> + <para>Below these configuration items you will find a field named<guilabel>Execute script on + connect:</guilabel>. Here you can enter the name of a script to execute after setting up + the network connection. It will be + executed whenever you hit the <guilabel>Activate configuration</guilabel> button and, + optionally, automatically when you start the Control Center module. The script will have + <systemitem class="username">root</systemitem> rights. This may lead to problems + if you want to start an X application in the script and the X server belongs to someone + else than root. You can make such scripts work correctly if you execute the X application + via<userinput> + <command>kdesu</command> + <option>-u</option> + <replaceable>USERNAME</replaceable> + <option>-c</option> + <replaceable>COMMAND</replaceable> + </userinput>. Or, you can instruct your X server to also allow connections coming from + root. You can do this with the <command>xhost</command> program.</para> + </sect3> + <sect3 id="config_crypto"> + <title>Cryptography settings</title> + <para>The checkbox <guilabel>Use encryption</guilabel> determines whether or not encryption + shall be activated. If it is checked, a button labelled <guibutton>Configure...</guibutton> becomes + available which allows you to configure the details of encryption. + After pushing the button, you are presented the following settings in a new dialog: </para> + <variablelist> + <varlistentry> + <term> + <guilabel>Key to use:</guilabel> + </term> + <listitem> + <para>You can define up to four secret keys for each configuration; in this field you + can set which one you want to use to send encrypted packets. The card can always + receive packets that are encrypted with <emphasis>any</emphasis> of the keys.</para> + <tip><para>You can achieve asymetrical encryption (different keys for sending and receiving) + if you configure your access point to send packets with a different key than the card. Just make + sure that the partner station has the required key in any one of its key slots.</para></tip> + </listitem> + </varlistentry> + <varlistentry> + <term> + <guilabel>Crypto mode:</guilabel> + </term> + <listitem> + <para>When encryption is activated, there are two ways to deal with incoming + non-encrypted packets: discard or allow. When you set your card for <guilabel>Open</guilabel>, + the card will also listen to non-encrypted packets. + <guilabel>Restricted</guilabel> will only allow encrypted network packets, + any other packets are discarded.</para> + </listitem> + </varlistentry> + <varlistentry> + <term> + <guilabel>Crypto keys:</guilabel> + </term> + <listitem> + <para>This box lets you specify the secret keys to use for cryptography. To protect + your passwords, only asterisks will be shown when you enter a password. The &kcontrolcenter; + module will automatically try to guess whether you want to set an encryption string + or a hexadecimal number by checking the input length: string keys are usually 5 or 13 + characters long (for 64- or 128-Bit key lengths) whereas hex values are 10 or 26 characters + long (please do not put a <quote>0x</quote> in front of hex keys).</para> + </listitem> + </varlistentry> + </variablelist> + <para>Be aware that the built-in cryptography support (named WEP for Wired Equivalent + Privacy) is not very safe at all. See <xref linkend="wep"/> for details.</para> + </sect3> + <sect3 id="config_power"> + <title>Power saving settings</title> + <para>The last configuration element that remains to be described is the power management. + When checking the box <guilabel>Enable Power Management</guilabel> a button for the + configuration of the setting will become active. After clicking this button, a new dialog will open + and you will be presented + some options that can help you save energy. The first two input fields named + <guilabel>Sleep timeout</guilabel> and <guilabel>Wakeup period</guilabel> + describe the periodicity of network online times for your wireless &LAN; card. The card will + turn the radio antenna off for the time period (in seconds) specified in + <guilabel>Sleep timeout</guilabel>. Afterwards it will be active for <guilabel>Wakeup + period</guilabel> and will in that time establish the network connection and send/receive + packets that queued up during the sleep time. If no network + connection is found, it will go to sleep again immediately and the cycle begins again. The box named + <guilabel>Receive packets</guilabel> below lets you specify which packets the card + should listen to when awaken. You can either select <guilabel>Unicast only</guilabel> + (which will only let your card listen to packets sent specifically to your card), + <guilabel>Multi/Broadcast only</guilabel> (will only listen to packets sent to multiple + machines and discard packets directed to your card) or <guilabel>Both</guilabel>. Most + people should select the default value <guilabel>Both</guilabel>.</para> + </sect3> + </sect2> + <sect2 id="auto-configuration"> + <title>Auto-configuration on &kcontrolcenter; Module startup</title> + <para> If you wish, you can make &kwifimanager; initialize your wireless &LAN; card + whenever you start the &kcontrolcenter; module. To do so, check the box <guilabel>Load + preset configuration on startup</guilabel> and select the configuration you want to use + in the listbox below. If you want to set the card to + these settings at once, push the button <guilabel>Activate + configuration</guilabel>.</para> + </sect2> + <sect2 id="autodetect"> + <title>Autodetecting your device</title> + <para>&kwifimanager; needs to know the interface name of your wireless &LAN; card to + apply any settings. You can either enter the information (⪚ + <userinput>eth1</userinput> or<userinput>wlan0</userinput>) manually in the input field + on the right-hand side of<guilabel>Settings apply to interface:</guilabel>, or let &kwifimanager; + auto-detect the interface. To do so, push the button<guibutton>Autodetect + interface</guibutton>. This will perform a scan on all interfaces listed in <filename + class="directory">/proc/net/dev</filename> to find your card. The result of the scan + will show up in the input field beside the button. If the field remains empty, no card was + found. Please note that &kwifimanager; uses the wireless extensions to detect cards. + If you use a card controlled by the wlan-ng package, &kwifimanager; only shows correct + results if your driver has a compatibility layer for the wireless extensions + built-in. In the case that there are multiple wireless LAN cards present on the system, + scanning stops after the first card found. So, if you want to apply the settings to a different + card than the one that was detected during the scan, you need to enter its interface name + by hand.</para> + </sect2> + </sect1> + </chapter> + <chapter id="credits"> + <title>License and contributors</title> + <para>Documentation copyright © Stefan + Winter<email>mail@stefan-winter.de</email>.</para> &underFDL; &underGPL; + <!-- TRANS:CREDIT_FOR_TRANSLATORS --> + </chapter> + <appendix id="further-information"> + <title>Further Information</title> + <para>This appendix contains some extra information of items concerning wireless &LAN; that + are not directly related to &kwifimanager;.</para> + <sect1 id="macaddress"> + <title>Notes on the MAC address display in Ad-hoc mode</title> + <para>At first glance, the MAC address in the field <guilabel>Access Point</guilabel> seems to + be wrong in Ad-hoc mode because it changes the first two digits of the MAC address + to<computeroutput>02</computeroutput>. But actually, this is a hardcoded feature in + wireless &LAN; cards.</para> + <para>Usually a card is connected to a <quote>real</quote> access point. Then the correct MAC + address is shown. If you change to Ad-hoc (or <quote>Peer-to-peer</quote>) mode, one of the + computers must act as a server for the other computers. The first computer that enters a + network will set itself as server. So, all other computers connecting to the same Ad-hoc + network will see that first computer as network server. But since this computer is not a + <quote>real</quote> server (that is, it is not a permanently available access point), + clients should be aware that the network they are connecting to is not a permanent one. IEEE + standards for MAC addresses have a place reserved for such (rare) occasions: MAC addresses that are + not globally valid have a bit set to one that shows that these addresses are + <quote>locally administered</quote>. This bit is the second bit in transmit order, and the seventh + bit in logical order and will hence raise the number of the MAC's first digit block from 00 to 02.</para> + <para>You can compare this sort of address to the non-global IP addresses like<quote>192.168.*.*.</quote> + </para> + <para>So, the implementors of wireless networking agreed to give these<quote>virtual</quote> + network servers a MAC address that is within the <quote>locally administered</quote> scope. + To keep this virtual MAC address unique, they used a little trick: they only changed the + first segment of the MAC address of the wireless &LAN; card, and since the remaining + segments are still unique in the world, they have a unique address to use as network + server.</para> + </sect1> + <sect1 id="wep"> + <title>Security considerations on <acronym>WEP</acronym> cryptography</title> + <para> + <acronym>WEP</acronym> cryptography is not very secure at all. A paper from + cryptography analysts called the encryption algorithm <quote>kindergarten + cryptography</quote>. Actually, software exists that exploits a huge security hole in the + encryption standard. This software listens to the encrypted network traffic, analyzes it, + and after only a few hours it reveals the password to enter the network in clear text. The + more traffic on the network, the easier it is to find out the password because some packets are + particularly weak because they carry a bad so-called initialisation vector (IV). Recent access + points try to avoid these bad IVs, so it is getting harder to exploit the hole.</para> + <para>If you are truly concerned about your security, do<emphasis>not</emphasis> use plain + <acronym>WEP</acronym>. If you are just setting up a two-computer home network, well, then + I guess<acronym>WEP</acronym> should do.</para> + <para>There are many alternatives to <acronym>WEP</acronym> encryption. Its successors WPA and + WPA2 are better designed and do a better job protecting your traffic, for example by dynamically changing + the keys after a while. + If you dont want to rely on the basic safety of the network link you could use + <acronym>SSH</acronym> to communicate over the network. <acronym>SSH</acronym> is a + program suite that encrypts data with its own algorithm, which is very secure. Another + option is to use <acronym>PPTP</acronym>, the Point-to-Point-Tunneling protocol. However, + even <acronym>PPTP</acronym> seems to be a bit leaky concerning encryption security. And + finally, you could set up an IPSec tunnel (VPN connection) for your encrypted connections. As of yet, this + encryption seems to be very safe and flexible.</para> + </sect1> + </appendix> + <appendix id="compile"> + <title>Compilation and Installation</title> &install.intro.documentation; + &install.compile.documentation;</appendix> &documentation.index;</book> |