This guide is focuses on Ubuntu users who needs to connect to Cisco VPN. We will be using VPNC (it is in Ubuntu 9.04) and assumes you have profile file in .pcf format (we will use cisco.pcf as an example here).

 
Let’s begin and follow the steps exactly replacing your own pcf file:
 

Open terminal and run the following commands. Create a directory for our configuration and change into that directory,

mkdir vpnclient
cd vpnclient

Download cisco-decrypt file which will be used to decrypt the group password from your pcf file:

wget http://www.debuntu.org/files/cisco-decrypt.c
sudo apt-get install libgcrypt11-dev
gcc -Wall -o cisco-decrypt cisco-decrypt.c $(libgcrypt-config --libs --cflags)
chmod +x cisco-decrypt
sudo cp cisco-decrypt /usr/bin

Download pcf2vpnc to convert pcf files in vpnc configuration format

wget http://svn.unix-ag.uni-kl.de/vpnc/trunk/pcf2vpnc
chmod +x pcf2vpnc
sudo cp pcf2vpnc /usr/bin

Go to windows vpn profiles directory and convert .pcf files to .conf files

pcf2vpnc cisco.pcf > cisco.conf
sudo cp cisco.conf /etc/vpnc/

Replace above cisco.pcf with your own .pcf file.

Install vpnc and connect to vpn

sudo apt-get install vpnc resolvconf
sudo vpnc cisco
Enter username for :
Enter password for :

VPNC started in background (pid: 6092)

To disconnect simply do

sudo vpnc-disconnect