The WSMan drive is accessible when PowerShell is running as administrator. The drive can be used to view and change the configuration of remoting.
For example, the provider can be used to update settings such as the MaxEnvelopeSize, which affects the maximum permissible size of SOAP messages sent and received by WSMan:
Set-Item WSMan:localhostMaxEnvelopeSizekb 1024
The WinRM service may need to be restarted after values are changed:
Restart-Service winrm