Exclusive: Juniper DX3680 boosts Web sites' speed and reliability
Transparent acceleration, protection, and encryption make this pricey load balancer worth the money
For non-HTTP traffic, a forwarder simply passes all traffic to the server cluster without processing it or accelerating the outgoing traffic. A redirector takes traffic addressed to a given address and sends it to a different one, without processing it at all.
A basic load balancing cluster can be set up quickly and easily. Adding functions such as encryption, server application protection, "sticky" sessions for e-commerce or other stateful transactions, and acceleration of Web traffic will make the cluster as complex as you like.
To test this system, I set up a standard Web site and simulated lots of clients accessing the site. The DX3680 should be able to handle large amounts of traffic without problems; in my testing, I had to use artificially small requests to generate any load on the system, but with normal requests, the system can handle more users than the network connection will support. (As for the DX3680's basic stats, it handles up to 256 HTTP proxy clusters; 1,024 server load balancing clusters; 64 servers per application cluster; 7,300 SSL transactions per second; 80,000 concurrent SSL connections; and 1.1 million concurrent SLB connections.)
Characterizing acceleration is more difficult – the amount of noticeable acceleration a user sees will vary greatly, depending on the type of application, how many users are on the system, which browser the user has, and many other factors. I tested response times for several types of Web transactions, including OWA, the serving of static pages, and a basic Java application, and found that applications were 30 to 400 percent faster than without the load balancer in place. One process that is simplified is converting a Web site from HTTP to HTTPS. Instead of rewriting all of the code on the site, the DX3680 handles the conversion automatically, and it takes care of the SSL processing, too.
The standard ruleset available when the DX3680 box is initially configured is called the Nitro.apprule. This set of rules protects against common attacks, causes clients to cache images, enables active acceleration of Web pages, and more. It's a simple starting point for getting acceleration working without having to do any programming.
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Additional features include quality of service, which can be specified separately for each cluster, and ActiveN clustering that makes adding more DX systems a simple process.
Pricey, but worth it
The Juniper DX3680 is not a system that someone would buy for simple load balancing. With a price as tested of $70,485 and a base price of $49,995, there are many less expensive load balancers out there that will create clusters of Web servers.
However, the system's sophisticated rules engine and acceleration features, as well as its ability to provide authentication, to protect Web servers and application servers, and to transparently add SSL encryption to a Web site without redoing code, will not be found on inexpensive load balancers. The DX3680 should allow even a small company to provide enterprise-class Web applications without a big investment in recoding.