Jetpack 3.3: Error - Connection timed out

If I want to complete the installation of the Jetpack 3.3, I have consistently a connection timed out error, although the IP address and the access data are entered correctly.

Return Code: 1
Error: Cannot connect to device with given information. Please check your input and try again.

Detailed info: 
ssh: connect to host port 22: Connection timed out

From the host, can you “ping”? Can you log in from the host via “ssh nvidia@”?

Are host and Jetson connecting to the same router?

Yes they are, I finally found the problem and there was a firewall Problem in the Network.

Can you tell me how to fix this problem?

Are the Jetson and host connected together on the same router? Can you ping the Jetson? Which release did you flash?