Dynamic Hybrid-Slot-Size Bandwidth Allocation Algorithm for Improving Quality of Services of Real Time Traffic in Ethernet Passive Optical Network (EPON)

Abstract

In the modern data networks, users are communicating via real time traffic, i.e., high priority (HP) traffic, very often. The demand is increasing for interruption free, high speed, high efficiency, and best quality of services to perform successful communications. This thesis emphasizes on the HP traffic like video conferencing, video chat, telemedicine, teleconferencing, and interactive gaming for the real time communication. In contrast, the low priority data is considered as the best effort (BE) traffic because the BE traffic do not require delay sensitive applications. To achieve better quality data communication for the HP traffic, Ethernet passive optical network (EPON) is used to fulfill the bandwidth demand of such real time traffic. The effectiveness of EPON mostly depends on dynamic bandwidth allocation (DBA) algorithm. In this thesis, we propose a new DBA algorithm called dynamic hybrid-slot-size bandwidth allocation (DHSSBA) algorithm. To ensure better performance, the proposed DHSSBA is also incorporated with the new multi-point control protocol (MPCP). As the DHSSBA scheme uses two Gate messages, one Gate message for the HP traffic and other one for the BE traffic, for each optical network unit (ONU) in a time cycle, the proposed MPCP protocol eliminates the synchronization problem between the two Gate messages. The performances of the proposed scheme are also compared with the existing hybrid-slot-size/rate (HSSR) scheme and delay variation guaranteed polling (DVGP) scheme. The performance of the proposed scheme has been analyzed by using numerical simulation in terms of the end to end packet delay, jitter variation and throughput for both the HP and BE traffic. From the comparison of the simulation results it is clear that the proposed scheme provides lesser end to end packet delay for the HP traffic and provides better performances than those of the HSSR and DVGP schemes.