no connection/ timeout
The SSH Server is protected with an IP blacklist.
An IP address will show up on the blacklist, if more than 3 logins (with an unknown user id) or 5 logins (with a known user id and a bad password) will occur during 5 days.
A successful login will reset the counter.
If you think your IP address has been blocked (indication: no password prompt appears), you can free your IP address:
http://www.math.uzh.ch/my > SSH > Open