In the last issue, I discussed a survey conducted by Port80 Software that looked at what the Fortune 1000 companies were doing to ensure that their Web content was correctly and effectively cached by caching proxies and client browsers.

The conclusion was that such a low percentage used cache control (only 21% of the 1,000 companies polled) and of those, only 28% did it right. In other words, only 6% of the Fortune 1000 are using caching correctly. Amazing. For a very good explanation of how caching should work see Port80's primer on the topic.

While correctly implemented caching has an immediate benefit in reducing bandwidth use; it also improves the browsing performance as experienced by the end user.

Port80's CacheRight product sets up and controls caching for IIS 4 on Windows NT, IIS 5 on Windows 2000, IIS 5.1 on Windows XP, and IIS 6.0 on Windows Server 2003.

CacheRight manages all cache control rules for a site by using a single text file that uses a simple rule syntax. The cache control can be site-wide, directory, or file-based, supports multiple virtual servers, and can be based on the MIME type of requested object.

The product, implemented as an ISAPI filter for high performance, includes a validation tool for checking rule syntax and supports all relevant HTTP 1.0 and 1.1 cache control headers including Expires and Cache-control (max-age, public/private, and no-transform).

There's also an online diagnostic tool for checking page "cacheability." CacheRight doesn't require access to the Microsoft Management Console but there is also an MMC snap-in for administration and default settings.

CacheRight is available as a free 30-day trial and a single server license for unlimited Domains costs $149.95.

Mark Gibbs is a consultant, author, journalist, columnist and blogger.