Incorrect, Bungie instantiated a P2P hybrid server, all ports are available, its a rogue server exclusion program. Right now the client server relationship is flawed in that us as the clients with University (type) internet are being lost in the Server Queue and being kicked out do to a lost Client ID. You can open those unnecessary ports, but your overall Network infrastructure being from a Uni is what is forcing the Exclusion protocol to "de-queue" us from the server. In a Stack sense, we get put onto the stack and a Search/Kill process comes through, checks our client ID, then loses it because of it's basic parameters, then places us back into the stack/queue (data type debatable) without out Client ID to send to the server then we are disconnected.