The future for Virtual Private Networks 8
The Internet has allowed much in the way of increased freedom for information collection and exchange. As a public medium of communication, transactions conducted over the Internet are often subject to the scrutiny of unauthorized individuals. In the past, prior to the widespread proliferation of the Internet and in the days when the large centralized, mainframe-based information structures reigned supreme. Because these structures were affordable by only the largest and most financially viable of organizations, sophisticated and highly ôsecureö private networks evolved that permitted the most private of transactions. The ease with which the Internet is utilized has forced the issue of secure communication and secure transaction down to the smaller size enterprise. Unfortunately, to obtain the same level of security brings with it a high cost of investment and continued ownership. The Virtual Private Network (VPN) has changed all of this. VPNs are able to connect remote users and remote LANs into functional networks. The following describes the VPN in terms of what it is, how it functions, the protocols utilized and its future direction.
By definition, a VPN is a private network configured within the public networking environment of the Internet. It is ôvirtualö because it does not comprise any lease lines since everything is transmitted over the Internet.
Private carriers have built VPNs that appear as private national or international networks to the customer but physically share backbone trunks with other customers. VPNs have typically been built over X.25, Switched 56, frame relay, and ATM technology. In order to maintain privacy in the public environment, VPNs utilize access control and encryption [1], using a ôtunnelingö protocol [2].
The tunneling protocol assures that data passing over the VPN is secure. In simplistic terms, tunneling is analogous to placi...