VPN Communication with IPSEC
IPSEC is Internet Protocol SECurity. It uses strong cryptography to provide both authentication and encryption services. Authentication ensures that packets are from the right sender and have not been altered in transit. Encryption prevents unauthorized reading of packet contents.
This solution works between two Linux firewalls or between a client machine (Windows 2000 or Windows XP) and a Linux based firewall. After several months of testing and client usage we have found IPSEC to be even more stable and effective than PPTP.