Yep openssh, the best thing microsoft did for windows 10 was to include openssh almost verbatim, rather than trying to make a native ssh. it does feel a bit foreign at times. but that is a good thing. can you imagine having to dig around in the windows trust store in order to make or use ssh keys. bust out regedit to change the config.... Shudder. Nope, it is perfect and works just like any other openssh install(within the limits of windows general weirdness)