Dynamic Bandwidth Allocation (DBA) in passive optical networks presents a key issue for providing efficient and fair utilization of the PON upstream bandwidth while supporting the QoS (Quality-of-Service) requirements of different traffic classes. In this paper, the authors compare the typical characteristics of DBA, such as bandwidth utilization, delay and jitter at different traffic loads, within the two major standards for PONs, Ethernet PON (EPON) and gigabit PON. They illustrate these differences between EPON and GPON (Gigabit PON). Industry standards for Passive Optical Network (PON) technology have enabled the initial deployment of Fiber To The Premise (FTTP) services.