To reduce the bandwidth used by Web traffic, HTTP was extended to allow more than one request within a single connection. This is called a persistent connection or you can say that the connection is kept alive.
If enabled, browsers can establish persistent connections. If disabled, the Web server will accept only one access per connection.
This specifies the number of seconds to wait for the next request in a persistent connection. If it is exceeded, the connection is closed.
The maximum number of requests allowed during a persistent connection.