VPN: is a secure connection between remote computer and a server on a private network that uses the internet as its medium by having the network permeantly connected to the internet by using a modem to dial-in to an ISP located nearby. Some ISP provides international services so the connection can be made internationally and with only a local call. The remote PC and remote access server establish a secure connection, which protects the data exchanged between them as it travels over the Internet called tunnelling. Some protocols associated with VPNS:
• Point-to-Point Tunneling Protocol: Created by the PPTP industry forum which included Microsoft, 3com ASCend, and ECI Telematics)
• Layer 2 Tunneling Protocol: A combination of PPTP and L2F (designed by CISCO)
• Internet Protocol Security: IPsec is an Architecture, protocol and related internet key exchange (IKE)