Tuning the Network for IIS

The following table describes network tuning parameters and their settings.

Parameter	Settings	Impact
Set receive buffers for the Network Interface Card (NIC) to maximum. If this is in a controlled environment or for a benchmark test, set it on both the client and the server.	See the documentation for your NIC for details. This parameter can often be set using the properties of the NIC under the Network Control Panel.	Dropped packets on the receiving end cause TCP to retransmit. This minimizes the number of dropped packets on the receiving end, thus increasing performance.
Set Transmission Control Protocol (TCP/IP) parameters in the registry.	Using Regedt32, navigate to HKLM\ CurrentControlSet\ Services\ TCPIP Parameters. Add the value MaxUserPort if it's not already there, and set it to 0xfffe. Add the value TcpWindowSize if it's not already there, and set it to 0x4470.	We don't want to run out of user ports. Also, a large window size works better for high-speed networks (TCP stops when the window fills up).

Parameter

Settings

Impact

Set receive buffers for the Network Interface Card (NIC) to maximum. If this is in a controlled environment or for a benchmark test, set it on both the client and the server.

See the documentation for your NIC for details. This parameter can often be set using the properties of the NIC under the Network Control Panel.

Dropped packets on the receiving end cause TCP to retransmit. This minimizes the number of dropped packets on the receiving end, thus increasing performance.

Set Transmission Control Protocol (TCP/IP) parameters in the registry.

Using Regedt32, navigate to HKLM\
CurrentControlSet\
Services\
TCPIP Parameters.

Add the value MaxUserPort if it's not already there, and set it to 0xfffe.

Add the value TcpWindowSize if it's not already there, and set it to 0x4470.

We don't want to run out of user ports. Also, a large window size works better for high-speed networks (TCP stops when the window fills up).