Cisco Network Design Solutions for Small-Medium Businesses

Virtual Private Networks

A VPN is typically defined as a private network operating over a shared infrastructure. By definition at least, a private network implies highly restricted access to authorized personnel only, transmission over the network that is secure from outside intrusion, and a quantifiable level of performance. Shared infrastructure potentially implies just the opposite: free-for-all access, lack of secure transmission, and no guarantee of performance. When a VPN is deployed over the Internet, a private network is operating over an insecure public network.

Given the success of the VPN technology, it's clear that the benefits associated with the private network have prevailed over the shortcomings of the shared environment. This ...