In addition to the standard modules mentioned in Chapter 1, which we suggest you compile into your copy of Apache, there are a number of more volatile modules available. We do not propose to document them in this edition of the book, but the list might be interesting. Be warned: modules designed for earlier versions of Apache may need updating before they work correctly with Version 1.3. Modules can be found in several places:
The Apache ../src/modules directory. This contains the standard modules plus (in the 1.3 release) subdirectories experimental and extra. The curious may find a search rewarding. At the time of writing there was only mod_mmap_static, which allows faster serving of slowly changing files.
The Apache FTP directory at ftp://ftp.apache.org/apache/dist/contrib/modules/. At the time of writing the list was as follows:
Disallow requests for files on particular devices.
Authenticate via cookies on-the-fly.
Authenticate via cookies with .htpasswd-like file.
Authenticate via external program.
Authenticate via instant passwords for dummy users.
Authenticate via system passwd file.
Bandwidth management on a per-connection basis.
Automatic caching of documents via mmap().
Automatic URL access counter via DBM file.
Disallow requests for files owned by particular user IDs.