Abstract: Method and system for allocating a transmission time slot to a node in a dynamic transmission network wherein nodes may have different Media Access Priority Levels. In a present schedule, each node is allocated a transmission allocation having in each transmission-access cycle a number of transmission time slots that is a function of a respective Media Access Priority Level of the node and wherein there is a registration slot allocation of at least one slot in an aggregation of cycles of communications slots. At least two nodes actively renew their respective transmission allocations in a next schedule by transmitting in at least one of its transmission allocation slots in a present schedule.