In the past, I've mentioned several products that accelerate Web server performance, but today we have one that I believe is unique - PipeBoost from BPVN Technologies (see editorial links below).

PipeBoost is an Internet Server Application Programming Interface (ISAPI) filter for Microsoft's Internet Information Server (Versions 4.0, 5.0, 5.1 and 6.0 are supported) and sits between the client browser and the actual Web server.

When a client requests content PipeBoost checks to see whether the browser can accept data compressed with GZIP or Deflate. If the browser can't handle compressed content, the browser unpacks the content and PipeBoost performs the compression and sends the data to the browser.

BPVN claims that compression only slightly increases CPU utilization for compression/decompression both on the server and client side, and that the content can be as small as one-tenth of the original file size with virtually no additional processor load. And because content compression occurs prior to Secure Sockets Layer encryption, there's a significant performance increase for sites that use SSL. There's a detailed technical description of how PipeBoost works on its Web site.

PipeBoost is highly configurable allowing compression to be specified globally or by Web site or Virtual Website; by directory; by individual file; by MIME type; or by client browser type providing nine levels of compression available. PipeBoost can also be adjusted for compression speed or compression size.

The product also provides content caching with its built-in "page smart" caching, which transparently caches static content in compressed form. This feature has been extended so that with a few changes to Active Server Pages code PipeBoost can cache dynamically generated Web pages and manage cache expiration.

PipeBoost also supports Microsoft XML 2.0+; provides statistical performance monitoring and reporting; supports ColdFusion Application Server for Microsoft IIS; supports Outlook Web Access for Microsoft Exchange Server to compress e-mail attachments; and offers usage monitoring and reporting.

Quite a spec, and at $1,499 per server, PipeBoost appears to be an interesting alternative to adding more servers and should certainly improve performance from the client's viewpoint.