Q:

How to increase maximum connection backlog limit in windows 2008 server

I have a Windows 2008 Server. Its maximum connection backlog limit (TCP) is 200. Is there any way to increase this limit to a higher value – say 1000 or 2000?
In this article you will find description of parameters to change in the registry under this key:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\AFD\Parameters

The relavant values should be these:

EnableDynamicBacklog (DWORD)
MinimumDynamicBacklog (DWORD)
MaximumDynamicBacklog (DWORD)
DynamicBacklogGrowthDelta (DWORD)

I have tried using different sets of values like

EnableDynamicBacklog = 1
MinimumDynamicBacklog = 250
MaximumDynamicBacklog = 20000
DynamicBacklogGrowthDelta = 100

and

EnableDynamicBacklog = 1
MinimumDynamicBacklog = 20
MaximumDynamicBacklog = 1000
DynamicBacklogGrowthDelta = 10

but no matter what I do I am still limited to a backlog of 200 connections. (And yes I have rebooted the server between configuration changes.)
Any ideas?

A:

Syn Attack protection has been implemented in TCP/IP stack of Vista and later OS. 
Therefore these registry parameters are no longer relevant.
Please refer to this technet article for more information about Syn Attack protection.

