VPN Definition

I’ve mentioned, in the last few sections, that VPNs can be used to deal with certain kinds of attacks. Therefore, the question is: What is a virtual private network (VPN)? Having worked in the computer field for almost twenty years, I am constantly asked to explain various technologies and what they are used for. In security, the most common question I’m asked is “What’s a VPN?” I’ve probably seen all possible explanations of what a VPN is, such as the following:

  • It’s an encrypted tunnel.

  • It uses IPsec, GRE, PPTP, SSL, L2TP, or MPLS (described later in the chapter).

  • It encrypts data.

  • It protects traffic across the Internet.

  • It protects your data from hackers and attacks.

As you can see, many people have different views or perceptions ...

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