hmmmm - i guess you are referring to something like
not in connection with safe but similar
and for safe:
but i’m pretty sure it’s that protocols can be hidden inside other protocols so it would look like https//ssl traffic
(the second link has a reference to something that might uncover us though as just hiding inside another protocol 
… [@nice s post 2 down from the think] … but didn’t read the rest - just an observation)