In this chapter, we will discuss goals and techniques concerning VPN security. These two terms are linked together very closely. Without security, a VPN is not private anymore.
Therefore, we will first have a look at basic security issues and guiding measures to be taken in a company. Information on symmetric and asymmetric keying methods, key exchange techniques, and the problem of security versus simplicity pave the way for SSL/TLS security and a closer look at SSL certificates. After having read this chapter, you will be prepared to understand the underlying security concerns of OpenVPN (and any other VPN solution).