Gigabit passive optical networks have been widely deployed due to the fact that the cost of their implementation is still decreasing. What is more important, we are facing theproblem with increasing demands on the transmission bandwidth. Regarding this issue, the ITU develops another two standards supporting higher downstream bitrate. The XG-PON standard is the first platform under the developing, and the NG-PON2 is the second standard. The first one provides compatibility and increases the downstream capacity of 10 Gbit/s and the second standard has the same assumptions, but does not have backward compatibility. In this article, we discuss only XG-PON networks. We choose amendment as the dynamic bandwidth allocation algorithms, and we have compared it with the original specification and with our modification. The primary intention of that modification is to reduce the delay of Triple Play (data, video, and voice) services. These services are represented by TCONT (Transmission Container), which is used to improve the PON system upstream bandwidth allocation and transmission status dynamically. As NS-3 simulator does not support the direct mapping of Triple Play services into T-CONT and their labeling. We focus on a delay value for Triple Play services which was reduced by own modification in a GIANT algorithm. On the other hand, we cannot reduce the delay value for VoIP services because it has the highest priority by T-CONT.
Modified GIANT Dynamic Bandwidth Allocation Algorithm of NG-PON
