$ ssh <username>@<IP_address>
Now you probably want to avoid taping this long command to connect to the platform. You can customize SSH aliases for that.
Edit the file
~/.ssh/config (create it if it does not already exist) and adding the following entries:
Host ap-cluster Hostname <IP_address> User <username> ServerAliveInterval 60
Now you shall be able to issue the following (simpler) command to connect to the cluster and obtain the welcome banner:
$ ssh ap-cluster