The Internet, Intranets, Extranets -- and VPNs

"Internet," "Intranet," and "Extranet" are terms widely used in our industry.  This session will define the terms and show that they are merely different perspectives of the same technologies.  And increasingly, Extranets are manifest as virtual private networks (VPNs).  But why?  Public networks are expensive and widely accessible, but traffic patterns vary widely and service guarantees are difficult to acheive.Private networks offer relatively high security and service levels but may be cost-prohibitive to deploy.  VPNs combine aspects of both private and public networks, and can provide some private network-like services over public network facilities.  The session introduces many aspects of VPNs, including security issues, tunneling protocols, products, and services.