Application Independence

Unlike a cache, Riverbed Steelhead appliances are application independent. Caches store copies of objects that may be requested by clients in the future so that the same data does not have to be sent again. The drawback is that a cache only works within a specific application. So a file cache will only help with requests for the same file, but will do nothing for web traffic, email, backup, ERP applications, or any other type of traffic.

Safety Versus High Performance

A cache stores copies of origin-server data, which by definition are not original copies. Therefore, there is a fundamental question with any cached data about safety versus performance. An operation is safe when the client is 100% certain that the data being requested is the actual data, not an out-of-date copy. With Riverbed Steelhead appliances, there is zero chance of data ever being out of date, because every single client request is passed through to the server, and the data received by the client is always fresh.

Ease of Deployment

Caches are proxies for origin servers, and therefore clients have to be configured to know about the proxy server. Unlike a cache, a Steelhead appliance is not a proxy server so clients need absolutely no configuration—they just access servers as always. The Steelhead appliances perform all optimizations completely transparently.