ABSTRACT
Virtual private networks (VPNs) have certainly received their fair share of press and marketing hype during the past few years. Unfortunately, a side effect of this information overload is that there now appears to be a great deal of confusion and debate over what the term “VPN” means. Is it synonymous with IPSec? Frame Relay? Asynchronous Transfer Mode (ATM)? Or is it just another name for remote access? If one were to take a quick survey of VPN information on the Internet, one would have to answer, “yes, it applies to all these technologies” (see Exhibit 1). This chapter first offers a definition that encompasses all these solutions. It then specifically discusses where the convergence of voice, video, and quality of service (QoS) fits in to this brave new VPN world. Finally, the discussion focuses on what offerings are deployable and testable today and what evaluation methodology to use in deciding which solution works best for a particular network.
