The aforementioned 50 years of OS development have given us facilities through which you can very tightly control what access you give to ssh clients, in a trie

The aforementioned 50 years of OS development have given us facilities through which you can very tightly control what access you give to ssh clients, in a tried and tested way. The authors are right when they say that sshd and unix users are probably the most frature-full auth scheme in existence.