Virtual Private Networks, or VPNs, have become a major networking technology within just the past few years. Does VPN technology live up to its own hype? How can a VPN improve your company? This article takes a look at what a VPN is, how it works, and how it can benefit your company.

What exactly is a VPN?
A VPN is essentially a private data network that uses existing telecommunications infrastructures (regular phone lines, T1 lines, DSL, cable lines, and so on). Privacy is achieved through the use of a tunneling protocol and security procedures. VPN technology enables company offices or individuals in different locations to securely access a central network without having to dial directly in to the company network.

VPN vs. traditional dial-in access
Connecting remote users via the traditional dial-in method can be costly. In order for employees to dial in to the network, the company needs a leased telephone line for multiple users to dial in on, as well as call-trafficking equipment (e.g., modems) to handle the incoming calls. A company must also consider the cost of these toll calls and the time their users stay connected. While the implementation of toll-free 800 numbers can alleviate some of this cost, there is still a significant fee for having an 800 number.

Sponsored by
NetScreen is the exclusive sponsor of TechRepublic’s special series on VPNs and Firewalls.

For more information, check out TechRepublic’s VPN and Firewall Center,
or visit NetScreen’s website.

NetScreen is the exclusive sponsor of TechRepublic’s special series on VPNs and Firewalls.

For more information, check out TechRepublic’s VPN and Firewall Center,
or visit NetScreen’s website.

By using a VPN, however, remote users can connect to an ISP with a local phone number and from there, tunnel securely to the office network. With this configuration, the only equipment needed is a VPN server, eliminating the need for leased lines and call-trafficking equipment. Toll calls and 800 numbers are also no longer an issue, as most national or global ISPs usually have local numbers for almost anywhere in the world.

Figure 1
The diagram above illustrates the difference between a dial-in connection and a connection with a VPN.

VPN for telecommuters
With more people working from home, remote-access VPNs have become an invaluable tool for many organizations. Users simply dial in to a local Internet Service Provider (ISP) and then establish a secure tunnel (with the VPN) to the office network. Users are then able to authenticate into their company’s network and browse as if they were in the office.

Imagine finding the perfect hire for a position, but that individual can’t relocate. VPN enables this employee to have access to the company network and the vital resources he or she needs from a remote location.

VPN for road warriors
One of the greatest benefits a VPN offers is to individuals who travel extensively. These individuals need frequent access to the company network for file sharing, checking e-mail, or other tasks that depend on connectivity. With a laptop, VPN, and global ISP, these road warriors can connect to the company network from anywhere there’s a phone line.

VPN offices around the country
What if your company’s main office is located in Miami, while your branch offices are located in Los Angeles, New York, and Chicago? While each branch has its own separate network, there aren’t many realistic ways to directly connect each office unless fiber was run between the locations. This would be very expensive.

With a VPN, however, each network can connect to the main office’s network and then to the other branch offices. All that’s needed is an Internet connection, a VPN server for each location, and an IP address to authenticate to.

Next time
Next week, we’ll be taking a look at hardware and software associated with VPN, and how VPN will change the way that companies currently network. We’ll also provide some links to other VPN sources on the Web for further information.
TechRepublic is featuring a series of articles on this topic in every Republic this month. If you’d like more information on security or productivity issues relating to VPNs, click here.