you may buy the VPN devices and deploy the devices at both the central and remote location. Or, establishing a Virtual Private Network (VPN) over the public Internet using a PC-based system and the IPSec protocol, in which expensive routers and firewalls were replaced by PCs and open source software.

This type of solution implies that both centres establish access connections to their respective Internet Service Provider (ISP), normally through a leased line to nearest Point of Presence (POP) of the selected provider. The VPN software ensures that the two computer systems are securely connected even with the use of a public network such as the Internet. This is done by creating tunnels, or secure communication paths between two peer centres using IPSec (Internet Protocol Security) protocol. The tunnels ensure complete privacy and data integrity by encrypting all data traffic between each centre intranet. This process takes place in the background and it is not visible to the users at the two sites.

The VPN technology used was based on using easily available PCs and the open source operating system Free BSD. Other license free software, such as Linux could be equally used. No additional software was required on the user’s PC to initiate the described secure connection. The use of public key cryptography for key exchange to establish the identity of one crypto server to the other make the data exchange highly secure.