The number of allowed simultaneous requests must be set.

Resource exhaustion can occur when an unlimited number of concurrent requests are allowed on a web site, facilitating a denial of service attack. Mitigating this kind of attack will include limiting the number of concurrent HTTP/HTTPS requests per IP address and may include, where feasible, limiting parameter values associated with keepalive, (i.e., a parameter used to limit the amount of time a connection may be inactive).