So what is Plan9's alternative to SSH?
SSL seems even worse than SSH in terms of algorithms that you have to negotiate, and thanks to misconfigurations you can end up in a situation with no shared ciphers (if server accepts only RC4 and client rejects RC4 for example).
According to that mailing list message cpu uses 9P+ssl, and I consider ssl more complex than ssh.
May not be the case on Plan9 as it looks like their ssl only supports old algorithms and not too many of them.
Maybe tinyssh could qualify as an alternative...