After choosing “Add”, you will see the deny rule settings window. In this window there are the following fields:
“Protocol” field contains list of popular nDPI library protocols (https://github.com/ntop/nDPI).
Important: nDPI library is included on “as-is” basis. Detection of application-related connection protocol by its signature depends entirely on the operation of this library. If the protocol cannot be determined, then the connection will not be blocked.