Concept of OpenSSH

OpenSSH is the secure alternative to the r utilities rlogin, rcp and rhs, and the programs telnet and ftp. In contrast to the aforementioned programs, OpenSSH encrypts all network traffic (including passwords) and thus prevents eavesdropping, connection hijacking, and other attacks at network level. Furthermore, OpenSSH supports a raft of tunneling variants and a wide range of authentication methods.