In speaking with people about SSH I have discovered that there is significant confusion between the release and protocol versions.
Stratus has released two versions of OpenSSL/SSH. Release 1 runs on the Continuum platform under VOS release 14.7x. Release 2 runs on the Vseries platform under releases greater than 15.0. The major difference is that release 1 does not support PTYs and requires the use of tunneling for interactive logins. Release 2 supports tunneling but also supports PTYs so that tunneling is not needed for interactive logins.
SSH also comes in 2 protocol versions, 1 and 2. These protocol versions are independent of the Stratus release versions. Both release 1 and release 2 support protocol versions 1 and 2.
Protocol version 1 has some known security issues. You may find references on the web suggesting that you disable version 1. Again, this refers to protocol version 1 and not the Stratus OpenSSL/SSH. release 1.
To disable protocol version 1 in the server change the Protocol directive in the >system>openssl>etc>sshd_config file