This extension allows persistent connections. It allows multiple requests to be send over the same TCP connection, and increase the performance by almost 50% for HTML documents with lots of images.
KeepAlive: This directive enables Keep-Alive support. Set max-requests to the maximum number of requests you want Apache to entertain per connection. A limit is imposed to prevent a client from hogging your server resources. Set this to 0 to disable support.
KeepAliveTimeout: The number of seconds Apache will wait for a subsequent request before closing the connection. Once a request has been received, the timeout value specified by the Timeout(in httpd.conf only) directive applies.