If you are in the market for a VPN, don't go past this review. We test the latest appliances and provide tips on purchasing and setting it up.

Generally speaking, with IPSec-compliant products you can build a secure VPN in any existing IP-based network.

We did however encounter a few problems trying to create a tunnel between two sites using two different VPN appliances. We imagine that this sort of thing would be happening out in the field as well. Ideally you would use appliances from the same vendor as it makes life so much easier.

IPSec also handles the encryption at the packet level. The protocol it uses is called ESP. ESP supports pretty much any kind of symmetric encryption. The default standard built into ESP that assures basic interoperability is 56-bit DES. Most of the appliances tested are capable (and were tested at) triple DES.

A VPN is a virtual private network, which is basically a private tunnel that connects two networks through a public network (usually the Internet). VPNs have been used to replace owned or leased lines so that a company can share the same capabilities but at a lower cost by using a shared public network.

A VPN works by encrypting data before sending it across a public network and decrypting it at the receiving end. Security features differ from product to product, but VPNs generally include encryption, authentication of remote users or sites, and mechanisms for disguising information about the private network from the public network. VPN functionality is often part of a firewall, so many of the appliances tested in this review include varying amounts of firewall functionality.

For this review we look at eight VPN appliances from the following vendors: Cyberguard, Fortinet, Juniper, Netgear, Nortel Networks, SonicWall, Symantec, and Watchguard.

How is the Data Secured?
The IPSec protocol suite provides a complete secure communications suite; with authentication, integrity, and confidentiality, and makes key exchange practical even in larger networks.