Follow the link below to read more about configuring specific SSH options. Like for example:
- Disable Password Authentication
- Disable Key Authentication
- Disable Forwarding
- Specify Which Accounts Can Use SSH
- Listen on a Non-Standard Port
- Reduce the Amount of Grace Time
- Log More Information
- Display a Banner
- Troubleshooting
https://help.ubuntu.com/community/SSH/OpenSSH/Configuring
