Some of these interfaces particularly the Epair, TAP and bridge interfaces might have weird names, don’t worry about that, even though we let users give whatever name they’d like to their switches/jails, we use a small hash as their names to avoid collisons and also to make sure we don’t make any mistakes in parsing/naming based on users input.
Nonetheless we try to make it as clear as possible which interface belongs to which switch/jail by showing the name of the switch/jail in the interface details, so you can easily identify them.