Increasingly, network administrators are turning to virtual private networking (VPN) connections to link remote workers to LANs. Windows 2000 includes VPN functionality, and even if you're not using VPNs at your organisation, you'll need to be familiar with Win2K's VPN feature if you're planning on sitting for any of the following exams:

• Exam 70-210 -- Installing, Configuring, and Administering Microsoft Windows 2000 Professional
• Exam 70-215 -- Installing, Configuring, and Administering Microsoft Windows 2000 Server
• Exam 70-216 -- Implementing and Administering a Microsoft Windows 2000 Network Infrastructure
• Exam 70-240 -- Microsoft Windows 2000 Accelerated Exam for MCPs Certified on Microsoft Windows NT 4.0

Why a VPN?
VPNs have caught on quickly primarily because they:

• Permit employees to connect to office resources from home or other locations using common hardware.
• Provide secure connections.

By using tunneling protocols, such as PPTP or LT2P, secure connections can be configured between a client's laptop or home machine and a company's LAN, as diagrammed in Figure A.

Figure A

VPNs use tunneling protocols to create secure connections through the Public Switched Telephone Network.

The Windows 2000 Network Connection Wizard offers two methods for connecting to private networks. The Network Connection Wizard can be reached by clicking Start | Settings | Network And Dial-up Connections | Make New Connection from within Windows 2000 Professional. The method you select will depend largely on the telecommunications technology you have in place. You should select Dial-up To Private Network if you plan to use a traditional 56Kbps modem or ISDN connection. You should select Connect To A Private Network Through The Internet if you wish to use a preexisting Internet connection. Most likely, if you're using a cable modem or a DSL connection, you'll choose this option.