If you utilise Microsoft Internet Information Services IIS or an application that uses the System.Net.HttpListener class is installed or running on one the operating systems below, and you have a Network Load Balancer then you may find that Increased latency occurs on HTTP and HTTPS requests and traffic.
This issue occurs because the HTTP and HTTPS requests from clients can include zero length data in the SSL records, certain server-side variables do not update correctly in this instance and Http.sys leaves the connection in the CLOSE_WAIT state. This intern exhausts the open connection limit can introduce latency, timeouts and connection problems.
Affected Operating Systems:
Microsoft Windows Vista
Microsoft Windows 7
Microsoft Windows Server 2008
Microsoft Small Business Server 2008 – SBS 2008
Microsoft Windows Server 2008 R2
Microsoft Small Business Server 2011 – SBS 2011
The Microsoft Knowledge Base Article KB 2634328 includes further information on this issue and provides an updated version of Http.sys that corrects the issue http://support.microsoft.com/kb/2634328