A frame division method for prioritized DBA in EPON

Dynamic bandwidth assignment (DBA) in Ethernet Passive Optical Networks (EPONs) is based on a frame structure that is broadcast downstream periodically. In most DBA schemes supporting priorities, frames are divided to allocate bandwidth for different traffic classes according to weights, which, however, are often either determined empirically or supposed to be pre-known. How to determine these weights dynamically according to quality of service (QoS) requirements and traffic loads has not been addressed adequately in the literature. This paper discusses a frame division method for supporting prioritized DBA for three traffic classes based on weights determined according to the traffic load and QoS requirement of each traffic class. This method is based on a frame structure that can efficiently support traffic prioritization by allocating per-frame bandwidth for each traffic class according to its medium access delay bound and traffic load. The method is investigated through computer simulation for voice, video and data applications. The simulation results show that it can properly allocate bandwidth to voice with little over-provisioned bandwidth while video can be efficiently prioritized at the expense of less support for data traffic