It means you will be able to come into my cabin without me opening it for you most of the time. You can always leave when you please, either way. Barring the barge pulling some bullshit.

[ Look, specific is important here and if he'sin the midst of sex, he is changing that filter and she can knock. But her having access to get into his cabin independent of the barge network is important enough to him to take the risk that comes with it. ]