9
Introduction to Virtual Private Networking
Virtual Private Networking (VPN) uses a publicly wired network (the
Internet) to connect two different networks as if they were the same
network. For example, an employee 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 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 their own VPN network making interoperability a
challenge.