Because TCP/IP stacks are designed to work efficiently on wired networks, performance can degrade on wireless networks. For example, settings appropriate to a 10 Mbps Ethernet connection may consume excessive bandwidth by generating unnecessary retransmission requests.
To use wireless networking efficiently, you may need to set some TCP/IP parameters to the characteristics of the supporting network. Because network parameters are maintained on a per-adapter basis, your application must determine the appropriate adapter and query the user for associated registry settings.
The following table shows the parameters that you may need to modify.
Registry parameter |
Description |
| TcpWindowSize | TCP receive window size registry key: HKEY_LOCAL_MACHINE\Comm\AdapterName\Tcpip\ Parms\TcpWindowSize. In general, larger receive windows work better with high-delay, high-bandwidth networks. For greatest efficiency, the receive window should be an even multiple of the TCP maximum segment size. It should not exceed the system maximum value in HKLM\Comm\AdapterName\Tcpip\Parms\ GlobalMaxTcpWindowSize. |
| TcpInitialRTT | Initial round-trip time (RTT) registry key: HKEY_LOCAL_MACHINE\Comm\Adapter Name\ Tcpip\Parms\TcpInitialRTT. The key value sets the initial RTT in milliseconds (msec). The default value is 3000 msec. The initial RTT is generally greater for wireless networks than for wired networks. |
| TcpDelAckTicks | Delayed acknowledgment timer registry key: HKEY_LOCAL_MACHINE\Comm\AdapterName\Tcpip\ Parms\TcpDelAckTicks. The default value is 200 milliseconds. |