N-GEN Communications Web-based Seminars ©NGCS

Seminar - An Overview of Communications Technologies

Module 7 - LAN, WAN, VPN, WLAN, MAN, FDDI and Optical MANS                                                      Slide 23 of 45 _________________                                                                                  __________

                                                What is a VPN ?


          

                                Wide-area Networking too Expensive

                                WAN Links Established Using the Internet

                                Encrypted Data From One Site to Other Site

                                Point-to-Point-Tunneling Protocol (PPTP)

_________________                                                                                  __________

WAN connections with expensive long distance facilities are too expensive for some applications. PPTP, a version of Point-to-Point Protocol (PPP), is used to provide a remote client with the ability to access a corporate network over the Internet. PPTP has compression and error checking built-in making it a reliable protocol. A Client requires special software to implement a Virtual Private Network within the Corporate network. Multiple protocols, like IP, IPX and Net BEUI, can be encapsulated in PPTP packets, which are in turn encapsulated in TCP/IP packets and routed across the Internet to a corporate VPN server. The corporate Server strips the TCP/IP and PPTP layers and the packet is routed on the local network as though the client were physically attached to the corporate network.