Passive Optical Networks offer quite promising results in terms of cost, robustness, flexibility and traffic concentration. The addition of Optical Amplifiers, overcame the optical budget limitations of fully passive first generation technology, enabling the extension of the PONs to up to 15000 subscribers and a 100 km distance, creating the concept of SuperPONs currently at the development stage. The larger round trip delay, as well as the high number of subscribers, coupled with the strict traffic control dictates of ATM, create very complex traffic control and management problems but at the same time open the prospects of high multiplexing gain by aggregating many relatively small connections on a shared feeder. Novel solutions are required since the tree topology and the shared feeder create new problems not encountered in non-distributed multiplexers/concentrators. Methods to resolve the VPI/VCI conflicts on the shared medium, support OAM, ensure privacy and security, police the entry to the system, and the traffic engineering issues, are the focal points of this paper.