Real Issue. I requested my Server Provider to change settings. Its reply was to use software supporting "ssl session reuse". I updated Java to Version 8 Update 131 (Build 1.8.0_131-b11) - no success. I also tried sublime text 3 with SFTP-Plugin, it has the same problem related to python implementation.
I still don't know who is in charge my Server Provider or Netbeans/Oracle? Still, any help would be greatly appreciated!