We discussed the various aspects of WAN design in this chapter. We also discussed the different WAN technologies that can be used by organizations, and the factors that influence the choice of one technology over the other. We delved deep into the different types of VPN services provided by different service providers, and the pros and cons of using each type of VPN. We also evaluated the use of public infrastructures to create secure WAN links using encryption techniques, and introduced some of the advanced concepts that can be evaluated as the WAN requirement grows in an organization.
In the next chapter, we will discuss the various technologies used in a data center.