Boa is a single-tasking HTTP server. That means that unlike
traditional web servers, it does not fork for each incoming
connection, nor does it fork many copies of itself to handle multiple
connections. It internally multiplexes all of the ongoing HTTP
connections, and forks only for CGI programs (which must be separate
processes.) Preliminary tests show boa is about twice as fast as
Apache, and is capable of handling 50 hits per second on a 66 MHz '486.
   
The primary design goals of Boa are speed and security. Security, in
the sense of "can't be subverted by a malicious user", not "fine
grained access control and encrypted communications". Boa is not
intended as a feature-packed server; if you want one of those, check
out WN from John Franks. Modifications to Boa that improve its speed,
security, robustness, and portability, are eagerly sought. Other
features may be added if they can be achieved without hurting the
primary goals.
   
Homepage:  http://www.boa.org