e98603ff_mod_proxy___Apache_HTTP_Server__Description
[Parameter] keepalive [Default] Off [Description] 
This parameter should be used when you have a firewall between your Apache and the backend server, who tend to drop inactive connections. This flag will tell the Operating System to send KEEP_ALIVE messages on inactive connections (interval depends on global OS settings, generally 120ms), and thus prevent the firewall to drop the connection. To enable keepalive set this property value to On.
mod_proxy - Apache HTTP Server
Description