Accessing the company network

How sensitive is your company's data? For most businesses, the answer is probably "very." Most businesses have customer information and records, financial records and company secrets in their internal networks that merit the best protection you can afford. On the other hand, if your sensitive data is stored offline, and you don't have anything online that you think a hacker might be interested in, perhaps you don't need a VPN.

Do you have telecommuters, travelling employees or other remote workers? The benefits of a VPN are twofold: Not only do they offer secure network access to those traveling or working offsite, but they extend the corporate network to those workers to make them feel a part of your team.

Do you have more than a few employees? A VPN may be an expensive solution for a company with fewer than five employees, unless they all travel or work remotely. Burney suggests companies with 10 or more employees are most likely to reap the economies of scale that a VPN can offer.

Do you have encrypted internet pages already? Some companies may already have the encryption protection necessary for remote workers - at least for accessing their email, says Matthew Berk, a technical research analyst. For businesses with low sensitivity requirements, he says, "there are web-based alternatives to a VPN for authentication and encryption," though they may be less secure.

Install yourself or use a managed service?

�If you have an IT staff or a consultant, you may want to buy and implement a VPN yourself.�

If you have an IT staff or a consultant, you may want to buy and implement a VPN yourself. You have more control over the setup and usage. But VPNs are often implemented incorrectly, and that can open up big security holes, Berk says. In addition, administration and management of VPNs in-house is complicated and "can be a hassle," says Jason Smolek, an analyst for IDC.

Some internet service providers offer managed security solutions that could save you the hassle. Many bundle their VPNs with a firewall.

Have a firewall too

Some users have a VPN instead of a firewall, but that isn't smart. The purposes of a VPN are to create an encrypted tunnel or gateway through your network's firewall and to keep out hackers. The VPN encrypts the pieces of data, but the firewall is still needed to provide a prison fence around your network. It makes little sense to have a VPN and not a firewall.

Look for "IPSec" compliancy and operating system compatibility.

IPSec stands for Internet Protocol Security, and is a VPN-supporting technology included in recent versions of Microsoft Windows. Used with compatible VPNs (and the majority are, according to analysts) IPSec guarantees the authenticity, integrity and confidentiality of network traffic. Interoperability with a VPN may be an issue, however, with Macintosh systems or older versions of Windows, Berk says. Make sure you buy a VPN compatible with your operating system.

If you have a wireless network, make sure your VPN operates securely with it.

Having a VPN certainly enhances the capabilities of your wireless network. But the "layering" of a VPN on a wireless network can result in security holes if not done properly. Dennis Eaton, chairman of the nonprofit Wireless Ethernet Compatibility Alliance (WECA), recommends that businesses place their wireless LAN outside of their network firewall, and provide the VPN to tunnel through the firewall, to ensure the utmost security. Otherwise, he says, wireless network traffic can accumulate and move around inside the firewall, virtually nullifying the VPN and risking security. "You want to make sure the firewall is on the inside and the wireless network on the periphery," Eaton says.

Know that a VPN may cause a performance hit for the remote user.

This happens when suddenly some 10% to 15% of the bandwidth you have available remotely goes to security. "VPNs are great for setting up a secure connection, but they take up a healthy chunk of the performance speed," says Joe Laszlo, broadband analyst for Jupiter Research. "It's not so bad that it is unusable, but in many cases, it is noticeable."

Despite this, Laszlo and other analysts say that if you need a secure connection for your remote and traveling workers, VPNs are worth the money. "Some smaller businesses are just getting to know them, and there is a perception among some that [VPNs] aren't that secure," Burney says. "The reality is that they are phenomenally secure."

Think a VPN sounds like overkill? Read about other ways to access your email when you're out of the office.

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