###Step 1: Install Necessary Packages We will need the vpnc package:
$ sudo aptitude install vpnc
###Step 2: Download the PCF file We now need to the connection details for Cornell's VPN which can be found in CornellVPN.pcf. If that link doesn't work, you may have better success here http://www.it.cornell.edu/services/vpn/howto/archive/pcfcampwinxp.cfm
###Step 3: Extract Connection Details In a terminal run the following command (from the same directory as CornellVPN.pcf)
$ pcf2vpnc CornellVPN.pcf
Take note of the IPSec secret field, you will need it later.
###Step 4a: Create VPN (GNOME) If you'd rather use a command line interface, or are not using GNOME, skip to step 4b below.
For this next part, you will need to have the GNOME vpnc network manager plugin installed. If you don't, just run sudo aptitude install network-manager-vpnc-gnome.
Now open the nework manager (Settings > Network) and click the + in the bottom right. Then then select VPN followed by Cisco Compatible VPN (vpnc).
Fill out the following entries:
Gateway: cuvpn.cuvpn.cornell.edu
Group Name: CornellVPN
Username: <netid>
Group Password: <IPSec secret>
Click add to complete the setup. At this point, everything should be setup so you can connect/disconnect from the Cornell VPN via the GUI, analogously to Wi-Fi. If prompted, enter your netid password.
###Step 4b: Create VPN (terminal) Open /etc/vpnc/default.conf in you favorite text editor and enter the following lines:
IPSec gateway cuvpn.cuvpn.cornell.edu
IPSec ID CornellVPN
Xauth username <netid>
IPSec secret <IPSec secret>
Now you can connect with sudo vpnc-connect and disconnect with sudo vpnc-disconnect. Enter your netid password when prompted.