Module 5: What is a Virtual Private Network (VPN)?
A VPN is a network that uses the internet to provide users secure access to their organizations network just like in a local area network. A VPN is created by using a cryptographic system to secure communication over an untrusted network (the Internet, a wireless LAN, etc.).
Host-to-host VPN connects a single client over an untrusted network to a single server.
Remote access VPN connects a single remote PC over an untrusted network to a site network.
Site-to-site VPN protects all traffic flowing over an untrusted network between a pair of sites.
References:
Samuelle, T., & Meyers, M. (2009). Network Security. In CompTIA security certification (2nd ed., p. 111). New York: McGraw-Hill.