mod_gzip uses the well established and publicly available IETF
Content-Encoding standards in conjunction with publicy available GZIP
compression libraries such as ZLIB to deliver dynamically compressed
content 'on the fly' to any browser or user-agent that is capable of
receiving it. It is a software based solution that runs perfectly in
conjunction with any Apache Web Server on both UNIX and Win32 platforms.

No additional client side software is required to use this product.

mod_gzip does not require ANY software to be installed on the client
side. There is no accompanying 'Plug-in' or 'Client Proxy' of any kind.
All you need is your current HTTP 1.1 compliant browser. All modern
browsers released since early 1999 are already capable of receiving
compressed Internet content via standard IETF Content Encoding if they
are HTTP 1.1 compliant.