F5, Juniper, Citrix, and Zeus offer similar kinds of compression and acceleration technologies, which Barracuda, Coyote Point, and Kemp don't offer. F5 has outstanding ease of use, even better than Juniper, which has some very easy-to-use automation technologies that make it very easy to secure a Web site by moving to SSL without recoding the site itself. F5 also offers an application security gateway, which none of the others do, although many users may already have this capability in a standalone appliance. F5 has added Web application acceleration since our last review was completed. Citrix offers the greatest variety of acceleration technologies, with Juniper a close second and Zeus not far behind, although the Zeus box is not as easy to use. Barracuda and Kemp offer good basic systems at very low prices, starting at less than US$2,000, while Coyote Point has an excellent higher capacity system that still costs much less than the F5, Juniper, Citrix, and Zeus offerings with all the bells and whistles.

All the systems can perform the basic load-balancing tasks of creating virtual clusters and directing traffic based on content or type of traffic. All will work for creating a sophisticated e-commerce application or SSL-based corporate portal. Acceleration is very much a "your mileage may vary" kind of application: The type of Web server, whether TCP/IP session persistence is enabled, and the types of content being served will all have major impacts on the effectiveness of acceleration techniques.

In most cases, the Internet link will be saturated before the capabilities of any of these systems is reached, unless your Internet link supports gigabit or higher speeds. What can make a difference is the number of rules used to route traffic. If you're planning on applying a large number of rules to handle traffic based on IP address and other parameters ("if the IP address is in this range, and the connection is HTTPS, then send the traffic to these servers"), then the faster processing engines of the F5, Juniper, and Citrix systems can make a difference.