regedit is the command to invoke registry editor.
it can be used for windows TCP tuning.
The Windows Registry is a hierarchical database that stores
configuration settings and options on Microsoft Windows operating
systems. It contains settings for low-level operating system
components as well as the applications running on the platform: the
kernel, device drivers, services, SAM, user interface and third party
applications all make use of the Registry. The registry also provides a
means to access counters for profiling system performance.
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