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Introduction to Virtual Private Networking
Virtual Private Networking (VPN) uses a publicly wired network (the Internet) to securely
connect two different networks as if they were the same network. For example, an em-
ployee can access the corporate network from home using VPN, allowing the employee
to access files and printers. Here are several different implementations of VPN that can
be used.
Point-to-Point Tunneling Protocol (PPTP)
PPTP uses proprietary means of connecting two private networks over the Internet. PPTP
is a way of securing the information that is communicated between networks. PPTP
secures information by encrypting the data inside of a packet.
IP Security (IPSec)
IPSec provides a more secure network-to-network connection across the Internet or a
Wide Area Network (WAN). IPSec encrypts all communication between the client and
the server whereas PPTP only encrypts the data packets.
Both of these VPN implementations are used because there is not a standard for VPN
server software. Because of this, each ISP or business can implement its own VPN
network making interoperability a challenge.
