When using Drastic software on Windows, for some operations the network settings must be altered to allow for the performance necessary for the workflow. This includes Net-X-Code for UDP/RTP/RTSP streams, SMPTE 2022-6, and SMPTE 2110 streams, and any other workflow that requires high throughput from the Windows network stack.

Optimizing Windows Network

DWORD: DefaultSendWindow

DWORD: DefaultReceiveWindow

Key:  HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\AFD\Parameters

Set the value to 0x10000 in both cases.

"DefaultSendWindow", "DefaultReceiveWindow" control TCP window size

DWORD: MaximumReassemblyHeaders

Key:  HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters

Set the value to 0xffff (this is the max value)

DWORD: FastSendDatagramThreshold

Key:  HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\AFD\Parameters

Set the value to 0x10000 (if you have 64k Jumbo frames available)

Set the value to 1500 (if you are using a traditional network)

DWORD: TcpWindowSize

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters

Set the value to 0x100000

"TcpWindowSize" controls the TCP window size

DWORD:Tcp1323Opts

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters

Set the value to 1

cp1323Opts - allows the scaling of the TCP window above 16k.

Source: http://technet.microsoft.com/en-us/library/cc938205.aspx

Disable Windows Scaling heuristics

netsh int tcp set heuristics wsh=disabled forcews=enabled

The wsh tag is legacy.  The forcews can be set to enabled or disabled.

TCP Auto Tuning

netsh int tcp set global autotuninglevel=disabled

The default is 'normal'.  Other possible settings include:

disabled: uses a fixed value for the tcp receive window. Limits it to 64KB.
highlyrestricted: allows the receive window to grow beyond its default value, very conservatively.
restricted: somewhat restricted growth of the tcp receive window beyond its default value.
normal: default value, allows the receive window to grow to accommodate most conditions.
experimental: allows the receive window to grow to accommodate extreme scenarios (It enables RWIN values of over 16 MB).

Enable Connnection Rate Limiting

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\Tcpip\Parameters] “EnableConnectionRateLimiting”=dword:00000000

Removes rate limiting of connections in Windows 7, 8, and 10

Cached Logons Count

[HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Winlogon]

"CachedLogonsCount"=dword:00000000

Change CachedLogonsCount to 50 (the max) or 0 (disabled)