After the latest Java updates you may have seen this message “Network connection has dropped” whenever trying to use viewer.jnlp
Go to your Java release lib folder, and comment/change the following lines on your java.security file
jdk.tls.disabledAlgorithms=SSLv3, RC4, MD5withRSA, DH keySize < 1024, \ EC keySize < 224, DES40_CBC, RC4_40
This issue is caused by Java disabling 3DES_EDE_CBC – after making the changes, relaunch your browser and you should be able to remote in again.