SharpSSH is a pure .NET implementation of the SSH2 client protocol suite. It provides an API for communication with SSH servers and can be integrated into any .NET application.
There needs to be more official work done before this can safely be used. There are too many bugs and the code is based off of old coding patterns that are finicky and can cause problems. Some of us have contributed some hacks and patches that make the library a bit more stable, but take this library literally 'as-is.' It definitely helps abstract SSH and once patched, does work pretty well, but I would not rely on it 100%.