The Gigabit Passive Optical Network（GPON） systems cannot meet some new service problems

such as increasing resolution requirements of video broadcasting in Internet Protocol Television（IPTV）. In order to solve these issues

an improved GIANT Dynamic Bandwidth Allocation（DBA） algorithm is proposed. By prioritizing the bandwidth of T-CONT

the bandwidth of T-CONT 1 is allocated to each Alloc-ID. Its main purpose is to reduce the delay of data

video

voice and other services. The proposed algorithm represents these services as transport containers

which are used to dynamically improve the uplink bandwidth allocation and transmission state of Passive Optical Network（PON） systems. The effectiveness of the proposed algorithm is verified by simulation results. Compared with the DBA-free method and the unmodified GIANT algorithm

the proposed algorithm can significantly reduce the latency of Hyper Text Transfer Protocol（HTTP） service and triple-play service. The latency of HTTP and Video on Demand（VoD） services are reduced by 0.30 and 0.35 ms

respectively.