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| − | =Introduction=
| + | #REDIRECT [[Virginia Tech Wifi]] |
| − | Since the 2008-2009 school year, there have been two options for
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| − | connecting to the Virginia Tech network by wireless card. One network,
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| − | called '''VT-Wireless''', operates by means of WPA2 Enterprise and is secured with EAP/TLS. The other network, called '''VT_WLAN''', is an unsecured, captive portal wireless network.
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| − | While connections to VT-Wireless are secure by default, and
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| − | require no user authentication once set up, the setup to connect to
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| − | VT-Wireless has a number of steps. In contrast, set up for connecting
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| − | to the unsecured VT_WLAN network is negligible, but you will be
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| − | required to manually authenticate each time you connect. [''NOTE: see [#VT_WLAN_Auto_Login below] for scripts on how to enable automated authentication to VT_WLAN.'']
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| − | The table below summarizes the advantages and disadvantages of connecting to the two wireless LANs.
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| − | | |
| − | <table style="text-align: center;" align="center" border="1" cellpadding="10">
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| − | | |
| − | <tbody><tr>
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| − | <td>
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| − | </td><th>VT-Wireless
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| − | </th><th>VT_WLAN
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| − | </th></tr>
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| − | <tr>
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| − | <th>Secure (Encrypted)<br /> Connection
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| − | </th><td> yes </td><td> no
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| − | </td></tr>
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| − | <tr>
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| − | <th>Setup
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| − | </th><td> involved </td><td> trivial
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| − | </td></tr>
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| − | <tr>
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| − | <th>Authentication
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| − | </th><td> automatic </td><td> manual[#VT_WLAN_Auto_Login *]
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| − | </td></tr></tbody></table>
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| − | =VT-Wireless=
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| − | The VT-Wireless network is secured by WPA with EAP/TLS encryption.
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| − | This encryption mechanism is put in place through a certificate
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| − | authentication mechanism.
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| − | ==Obtaining the VT-Wireless Certificate==
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| − | Regardless of what program you use to make your connection, you will need to [https://netcert.cns.vt.edu/netcert/ obtain your p12 certificate and password from CNS].
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| − | Complete the form and download the p12 certificate file. Write down the
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| − | certificate password and store it some place where you can find it
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| − | again. You will need it in setting up your connection to VT-Wireless.
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| − | | |
| − | ===Connecting by NetworkManager===
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| − | The setup for NetworkManager depends on your version of the
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| − | software. Please follow the instructions appropriate to your version
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| − | below.
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| − | In GNOME, you can right-click the NetworkManager applet icon in
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| − | the panel and select "About" to find the version of NetworkManager.
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| − | Ubuntu users: version 0.6 ships with 8.04 Hardy Heron, and 0.7 ships
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| − | with 8.10 Intrepid Ibex.
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| − | | |
| − | ====NetworkManager 0.7====
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| − | ====Converting the certificate to PEM certificates and keys====
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| − | ['''NOTE:''' The following steps are only necessary to use NetworkManager 0.7. NetworkManager 0.6 has a [#NetworkManager_0.6 more straightforward setup] and wpa_supplicant works pretty much [#Connecting_by_WPA_Supplicant out of the box] as well.]
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| − | You will need to convert the p12 certificate into PEM formats. We will assume your downloaded p12 file is called '''<tt>netcert-1.p12</tt>''' and that its password is '''''netcertpasswd'''''.
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| − | Open a terminal and <tt>cd</tt> to the directory that contains your p12 file. Then issue the following commands:
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| − | | |
| − | <pre>openssl pkcs12 -in netcert-1.p12 -out vt_client_cert.pem -clcerts -nokeys
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| − | openssl pkcs12 -in netcert-1.p12 -out vt_private_key.pem -nocerts
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| − | </pre>
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| − | In each step, you will be prompted for the password (''netcertpasswd'')
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| − | that you were issued along with your p12 certificate. Additionally, in
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| − | the final step where you generate your private key, you will be asked
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| − | to enter a password. Enter the same password that came with your p12
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| − | key.
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| − | '''Sources'''
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| − | | |
| − | <ul><li> [http://www.codealias.info/technotes/wpa2_eap-tls_authentication_linux_client_setup http://www.codealias.info/technotes/wpa2_eap-tls_authentication_linux_client_setup]
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| − | </li></ul>
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| − | ==== Make sure you have the CA Certificate ====
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| − | Next, you will need to make sure you have the Thawte CA certificate. In Ubuntu, you should find this certificate as <tt>/etc/ssl/certs/Thawte_Premium_Server_CA.pem</tt>.
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| − | If you can't find the certificate, you can copy the text below and paste it into a new file of the same name.
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| − | | |
| − | <pre>-----BEGIN CERTIFICATE-----
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| − | MIIDJzCCApCgAwIBAgIBATANBgkqhkiG9w0BAQQFADCBzjELMAkGA1UEBhMC
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| − | WkExFTATBgNVBAgTDFdlc3Rlcm4gQ2FwZTESMBAGA1UEBxMJQ2FwZSBUb3du
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| − | MR0wGwYDVQQKExRUaGF3dGUgQ29uc3VsdGluZyBjYzEoMCYGA1UECxMfQ2Vy
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| − | dGlmaWNhdGlvbiBTZXJ2aWNlcyBEaXZpc2lvbjEhMB8GA1UEAxMYVGhhd3Rl
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| − | IFByZW1pdW0gU2VydmVyIENBMSgwJgYJKoZIhvcNAQkBFhlwcmVtaXVtLXNl
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| − | cnZlckB0aGF3dGUuY29tMB4XDTk2MDgwMTAwMDAwMFoXDTIwMTIzMTIzNTk1
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| − | OVowgc4xCzAJBgNVBAYTAlpBMRUwEwYDVQQIEwxXZXN0ZXJuIENhcGUxEjAQ
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| − | BgNVBAcTCUNhcGUgVG93bjEdMBsGA1UEChMUVGhhd3RlIENvbnN1bHRpbmcg
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| − | Y2MxKDAmBgNVBAsTH0NlcnRpZmljYXRpb24gU2VydmljZXMgRGl2aXNpb24x
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| − | ITAfBgNVBAMTGFRoYXd0ZSBQcmVtaXVtIFNlcnZlciBDQTEoMCYGCSqGSIb3
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| − | DQEJARYZcHJlbWl1bS1zZXJ2ZXJAdGhhd3RlLmNvbTCBnzANBgkqhkiG9w0B
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| − | AQEFAAOBjQAwgYkCgYEA0jY2aovXwlue2oFBYo847kkEVdbQ7xwblRZH7xhI
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| − | NTpS9CtqBo87L+pW46+GjZ4X9560ZXUCTe/LCaIhUdib0GfQug2SBhRz1JPL
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| − | lyoAnFxODLz6FVL88kRu2hFKbgifLy3j+ao6hnO2RlNYyIkFvYMRuHM/qgeN
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| − | 9EJN50CdHDcCAwEAAaMTMBEwDwYDVR0TAQH/BAUwAwEB/zANBgkqhkiG9w0B
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| − | AQQFAAOBgQAmSCwWwlj66BZ0DKqqX1Q/8tfJeGBeXm43YyJ3Nn6yF8Q0ufUI
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| − | hfzJATj/Tb7yFkJD57taRvvBxhEf8UqwKEbJw8RCfbz6q1lu1bdRiBHjpIUZ
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| − | a4JMpAwSremkrj/xw0llmozFyD4lt5SZu5IycQfwhl7tUCemDaYj+bvLpgcU
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| − | Qg==
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| − | -----END CERTIFICATE-----
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| − | </pre>
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| − | <br />
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| − | Left-click the NetworkManager applet and select the VT-Wireless network.
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| − | <a href="http://www.vtluug.org/wiki/index.php?title=Image:Nm_choose_wireless.png" class="image" title="Image:nm_choose_wireless.png"><img alt="Image:nm_choose_wireless.png" src="VT-Wireless_files/Nm_choose_wireless.html" height="255" width="313" border="0"></a>
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| − | You will see a prompt to configure the connection. First, from the Authentication drop-down menu, select TLS.
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| − | <a href="http://www.vtluug.org/wiki/index.php?title=Image:Nm_choose_tls.png" class="image" title="Image:nm_choose_tls.png"><img alt="Image:nm_choose_tls.png" src="VT-Wireless_files/Nm_choose_tls.html" height="466" width="494" border="0"></a>
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| − | Next, fill in the rest of the options:
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| − | <a href="http://www.vtluug.org/wiki/index.php?title=Image:Nm_vt_wireless_options.png" class="image" title="Image:nm_vt_wireless_options.png"><img alt="Image:nm_vt_wireless_options.png" src="VT-Wireless_files/Nm_vt_wireless_options.html" height="466" width="494" border="0"></a>
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| − | | |
| − | <table align="center" border="1" cellpadding="5">
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| − | | |
| − | <tbody><tr>
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| − | <th>Field </th><th> Value
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| − | </th></tr>
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| − | <tr>
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| − | <th>SSID
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| − | </th><td>VT-Wireless
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| − | </td></tr>
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| − | <tr>
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| − | <th>Wireless Security
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| − | </th><td> WPA & WPA2 Enterprise
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| − | </td></tr>
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| − | <tr>
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| − | <th>Authentication
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| − | </th><td> TLS
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| − | </td></tr>
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| − | <tr>
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| − | <th>Identity
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| − | </th><td>''Your VT PID''
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| − | </td></tr>
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| − | <tr>
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| − | <th>User Certificate
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| − | </th><td> /path/to/vt_client_cert.pem
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| − | </td></tr>
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| − | <tr>
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| − | <th>CA Certificate
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| − | </th><td> /etc/ssl/certs/Thawte_Premium_Server_CA.pem
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| − | </td></tr>
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| − | <tr>
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| − | <th>Private Key
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| − | </th><td> /path/to/vt_private_key.pem
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| − | </td></tr>
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| − | <tr>
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| − | <th>Private Key Password
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| − | </th><td> ''netcertpasswd''
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| − | </td></tr></tbody></table>
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| − | Click "Connect" and you should connect to the VT-Wireless network.
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| − | | |
| − | ===NetworkManager 0.6===
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| − | Left-click the NetworkManager applet and select VT-Wireless. You
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| − | will be prompted to enter information about the connection. Here are
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| − | the entries you should use:
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| − | | |
| − | <table align="center" border="1" cellpadding="5">
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| − | | |
| − | <tbody><tr>
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| − | <th>Field </th><th> Value
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| − | </th></tr>
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| − | <tr>
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| − | <th>SSID
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| − | </th><td>VT-Wireless
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| − | </td></tr>
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| − | <tr>
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| − | <th>Wireless Security
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| − | </th><td> WPA2 Enterprise
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| − | </td></tr>
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| − | <tr>
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| − | <th>EAP Method
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| − | </th><td> TLS
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| − | </td></tr>
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| − | <tr>
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| − | <th>Key Type
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| − | </th><td>Automatic (Default)
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| − | </td></tr>
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| − | <tr>
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| − | <th>Phase2 Type
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| − | </th><td> None (Default)
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| − | </td></tr>
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| − | <tr>
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| − | <th>Identity
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| − | </th><td>''Your VT PID''
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| − | </td></tr>
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| − | <tr>
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| − | <th>Password
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| − | </th><td> ''empty''
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| − | </td></tr>
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| − | <tr>
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| − | <th>Client Certificate File
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| − | </th><td> (None)
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| − | </td></tr>
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| − | <tr>
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| − | <th>CA Certificate File
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| − | </th><td> (None)
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| − | </td></tr>
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| − | <tr>
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| − | <th>Private Key File
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| − | </th><td> netcert-1.p12 <br />(the certificate downloaded<br />from VT NetCert)
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| − | </td></tr>
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| − | <tr>
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| − | <th>Private Key Password
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| − | </th><td> ''netcertpasswd''
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| − | </td></tr></tbody></table>
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| − | ==Connecting by wicd(wicked)==
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| − | Wicd is an alternative to network manager and is used on many light
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| − | weight systems since it has few requirements and uses your systems own
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| − | ifconfig/iwconfig commands.
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| − | It still under active devlopment but is more than stable enough
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| − | for everyday use. Also NetworkManager has a tendancy to disconnect
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| − | every 10 minutes for about 20 seconds then it automatically reconnects.
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| − | Not a show stopper but could be annoying during a web-based
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| − | assignments.
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| − | Instead of using TLS, we will be using PEAP. This is a
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| − | different encryption scheme and is much more simple to setup compared
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| − | to TLS. I will also try setting up networkmanager with this method
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| − | later...
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| − | OK, do you have a VPN password? If not, follow these instructions for setting up your remote VPN login account[http://answers.vt.edu/kb/entry/2846/ [1]].
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| − | <br />
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| − | Next you need to locate the copy of the Thawte_Premium_Server_CA.pem on your system.
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| − | For me it was in:
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| − | | |
| − | <pre>/etc/ssl/certs/
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| − | </pre>
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| − | After dillegently locating this file, open up network manager.
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| − | Click san to make sure your list of devices is up to date.
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| − | Next click the "Properties" button next to the VT-Wireless at the top of the list (any one is fine really).
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| − | Make sure there is a check in both "Use these settings for all networks sharing this essid" and "Use encyption".
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| − | Next in the drop down box right below choose "PEAP with TKIP/MSCHAPV2"
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| − | This will present you with "Identity", "Password", and "Path to CA Cert" text boxes.
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| − | | |
| − | <pre>Identity: <Your PID>
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| − | Password: <The one you set up earlier for VPN access>
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| − | Path to CA Cert: <something like /etc/ssl/certs/Thawte_Premium_Server_CA.pem>
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| − | </pre>
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| − | Then just click OK.
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| − | | |
| − | <ul><li>Note: wicd will "star" out your identity and the path to the CA
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| − | Cert feilds so don't be alarmed when your ID and the path to the CA
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| − | Cert get transformed automatically to * when you click away from the
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| − | text box.
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| − | </li><li>Note: This method works for connecting iPhone(s)/iPod Touch(s)
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| − | </li></ul>
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| − | <ul><li>These Instructions are based on my own personal setup
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| − | </li></ul>
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| − | <pre>Eee PC 901
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| − | Ralink rt2860 (staging driver in kernel)
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| − | ArchLinux
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| − | Xfce 4.6
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| − | wicd 1.6.2
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| − | kernel 2.6.30
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| − | </pre>
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| − | ==Connecting by WPA Supplicant==
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| − | ===Editing wpa_supplicant.conf===
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| − | Add the following to your <tt>/etc/wpa_supplicant.conf</tt> file (if no file exists, create it):
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| − | | |
| − | <pre>network={
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| − | ssid="VT-Wireless"
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| − | key_mgmt=WPA-EAP
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| − | eap=TLS
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| − | identity="PID"
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| − | private_key="/PATH/TO/NETCERT.p12"
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| − | private_key_passwd="PASSWORD"
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| − | }
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| − | </pre>
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| − | Replace PID with your actual PID (without any trailing @vt.edu),
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| − | /PATH/TO/NETCERT.p12 with the actual path to your certificate (you can
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| − | store it in /etc) and PASSWORD with the certificate password given to
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| − | you when you downloaded the certificate. Note the certificate used here
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| − | should be the original one you downloaded. Reformatting the certificate
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| − | is only necessary for NetworkManager 0.7.
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| − | | |
| − | ===Running WPA Supplicant===
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| − | ====Ubuntu====
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| − | In Ubuntu, make sure to shut down NetworkManager with:
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| − | | |
| − | <pre>sudo /etc/init.d/NetworkManager stop
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| − | </pre>
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| − | Next, issue the following command:
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| − | | |
| − | <pre>sudo wpa_supplicant -B -i wlan0 -D wext -c /etc/wpa_supplicant.conf
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| − | </pre>
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| − | Confirm that you are associated with VT-Wireless
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| − | | |
| − | <pre>sudo iwconfig INTERFACE
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| − | </pre>
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| − | where <tt>INTERFACE</tt> is your wireless card's device interface. Usually this is <tt>wlan0</tt> but depending on udev and perhaps other system features, it might appear as ath0, eth1 or something else. Run <tt>sudo ifconfig -a</tt> to see all your interfaces listed.
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| − | You should see the words <tt>Access Point:</tt> followed by a MAC address (e.g., <tt>00:0F:23:EA:4A:01</tt>). If instead you see <tt>Access Point: not associated</tt>. Try the command again. If that still fails, bring down the interface and bring it back up
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| − | | |
| − | <pre>sudo ifconfig INTERFACE down
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| − | sudo ifconfig INTERFACE up
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| − | </pre>
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| − | and re-issue the <tt>wpa_supplicant</tt> command.
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| − | Next, obtain an IP address. In Ubuntu, this is done with
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| − | | |
| − | <pre>sudo dhclient INTERFACE
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| − | </pre>
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| − | If all goes well, you'll obtain an IP address. Otherwise, you'll receive a timeout for your DHCP request.
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| − | | |
| − | ====Gentoo====
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| − | If you're already using wpa_supplicant, just restart your interface:
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| − | | |
| − | <pre># /etc/init.d/wlan0 restart
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| − | </pre>
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| − | This should connect you.
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| − | If you're not using wpa_supplicant, you'll need to migrate from
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| − | Wireless Tools to it in order to speak WPA and 802.1X to the
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| − | VT-Wireless network. Refer to the [http://www.gentoo.org/doc/en/handbook/handbook-x86.xml?part=4&chap=4#doc_chap2 Gentoo documentation] for a step-by-step guide to setting up WPA Supplicant.
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| − | | |
| − | =VT_WLAN=
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| − | VT_WLAN service is available in approximately 90% of academic and
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| − | administrative spaces across the Blacksburg campus. This wireless
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| − | network is composed of unencrypted IEEE 802.11g access nodes. To limit
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| − | access to faculty and staff, VT Communications Network Services uses an
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| − | authentication technology from Bluesocket. You have to register for [http://www.cns.vt.edu/html/wireless/wlan/registration.html Customer OnLine Access (COLA)] or in person at the Student Telecommunications Office to enable your account.
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| − | | |
| − | ==Authentication==
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| − | The Bluesocket authentication technology will automatically redirect
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| − | you to the login page (or hijack the URL you are trying to visit in
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| − | some cases [cache related?], leading to SSL certificate problems).
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| − | Simply type in your PID and password to be granted access.
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| − | | |
| − | ==Logging in from the Command Line==
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| − | You can use CURL to log in from the command line or automate the process.
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| − | | |
| − | <pre>curl -d which_form=reg -d _FORM_SUBMIT=1 -d bs_name=YOUR_PID -d bs_password=YOUR_PASSWORD \
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| − | -d source=`/sbin/ifconfig eth1 | grep 'inet addr:' | cut -d: -f2 | awk '{ print $1}'` \
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| − | https://`/sbin/route | grep -Eo '(bur|cas|hil|isb|owe|sha)-agw-[123]'`.cns.vt.edu/login.pl</pre>
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| − | Here is a modified version of the above script so you do not have to
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| − | store your user name and password. Save it to a file.. 'chmod +x
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| − | the_file' then run it like so './the_file USER PASS' Note: By doing
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| − | this the command you use (with your username and pass) will be stored
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| − | in ~/.bash_history. You might wish to delete that file (or edit it).
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| − | | |
| − | <pre>#!/bin/bash
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| − | curl -d which_form=reg -d _FORM_SUBMIT=1 -d bs_name=$1 -d bs_password=$2 \
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| − | -d source=`/sbin/ifconfig eth1 | grep 'inet addr:' | cut -d: -f2 | awk '{ print $1}'` \
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| − | https://`/sbin/route | grep -Eo '(bur|cas|hil|isb|owe|sha)-agw-[123]'`.cns.vt.edu/login.pl</pre>
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| − | <br />Depending on the characters in your password, you may need to
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| − | quote it to prevent expansion, i.e. bs_password='MY!$?*PASSWORD'.
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| − | ifconfig and route are located in /sbin and therefore generally not in
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| − | the $PATH of a normal user. You should be able to run them as such,
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| − | however.
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| − | | |
| − | ==VT_WLAN Auto Login==
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| − | Although now antiquated, the following entry put in
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| − | /etc/conf.d/wireless on a Gentoo machine using Wireless Tools would
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| − | insecurely but automatically sign in to VT_WLAN.
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| − | | |
| − | <pre>postup() {
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| − | if [[ ${IFACE} = "wlan0" ]]; then
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| − | ROUTER="$(/sbin/route | grep -Eo '(bur|cas|hil|isb|owe|sha)-agw-[123]')"
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| − | | |
| − | if [[ ! "x${ROUTER}" = "x" ]] ; then
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| − | IP="$(/sbin/ifconfig eth1 | grep 'inet addr:' | cut -d: -f2 \
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| − | | awk '{ print $1}')"
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| − | | |
| − | curl -k -f -s -d which_form=reg -d _FORM_SUBMIT=1 \
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| − | -d bs_name=PID \
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| − | -d bs_password=PASSWORD \
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| − | -d source=${IP} \
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| − | https://${ROUTER}.cns.vt.edu/login.pl
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| − | return $?
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| − | fi
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| − | fi
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| − | return 0
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| − | }</pre>
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| − | PID and PASSWORD should of course be your PID and password. This
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| − | setup is only really suitable for a single user machine like a laptop.
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| − | To very slightly improve security you should <tt>chmod a-r /etc/conf.d/wireless</tt>. This script does not authenticate the access point and would send your password to rogue access points. Using [#VT-Wireless VT-Wireless]
| |
| − | rather than this script to automate login is highly recommended. If you
| |
| − | insist on ugly hacks then you could perhaps look into using the [http://www.vtluug.org/wiki/index.php?title=VT_VPN VPN] on top of VT_WLAN.
| |
| − | | |
| − | ==Some Technical Details==
| |
| − | The access points force SSL and are all signed by the Thawte Premium Server CA. The routers are named:
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| − | | |
| − | <ul><li> bur-agw-2.cns.vt.edu
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| − | </li><li> bur-agw-3.cns.vt.edu
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| − | </li><li> cas-agw-?.cns.vt.edu
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| − | </li><li> hil-agw-?.cns.vt.edu
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| − | </li><li> isb-agw-?.cns.vt.edu
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| − | </li><li> owe-agw-1.cns.vt.edu
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| − | </li><li> sha-agw-1.cns.vt.edu
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| − | </li></ul>
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| − | Generally, in order to minimize congestion, connectivity is spread across multiple channels. Channel 11 seems to be the busiest.
| |
| − | No MAC-based authentication is performed.
| |
| − | DHCP is independent of of the Bluesocket authentication and occurs first.
| |
| − | All wireless networks (including the .1x networks) on campus now
| |
| − | use RFC-1918 addresses from the 172.31.0.0/16 network. These are
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| − | translated with NAT into 198.82.x.x addresses for access outside the
| |
| − | wireless network.
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| − | All of the .1x wireless networks support IPv6. Some of the VT_WLAN networks support IPv6.
| |
| − | You can access certain VT sites like [http://www.cns.vt.edu/ CNS] without having to authenticate.
| |
| − | | |
| − | =Network Information Sources=
| |
| − | <ul><li> [http://www.cns.vt.edu/html/wireless/wlan/index.html Communications Network Services: Wireless LAN]
| |
| − | </li><li> [http://computing.vt.edu/internet_and_web/internet_access/ipaddresses.html Virginia Tech IP Addresses]
| |
| − | </li></ul>
| |
