I understand that there are supposed to be three different matrix modes: hidden, passive and active. I can understand the distinction between active and hidden, but I've been having trouble figuring out what the real distinction between Active and Passive mode is. Can someone explain more clearly? I've read both unwired and SR4A trying to get the distinction clearer, but I'm still confused.

• Active: The node is visible and set up to react to data requests from all other nodes, the "Public Access" rights determine what information and services are available.
  (You are basically carrying a big virtual sign with an arrow on it, pointing towards you, along with name and phone number in big letters.)
• Passive: The node is visible, but only reacts to data requests from defined nodes/users or upon individual confirmation.
  (You no longer have the sign, but you still have some kind of ID on you, and your phone will accept any incoming calls, as your Commcode Provider is authorised.)
• Hidden: The node is invisible, and only reacts to data requests from defined nodes/users. Sending a data request to a node makes you visible for that node.
  (You don´t broadcast any ID data, and your phone only accept calls from your list of known numbers.)

(Source.)