Video Traffic Prioritization in WLANs Using Single Queue Priority Scheduler

摘要

Mobile video transmission poses many challenges in standard wireless networks like Wireless Local Area Network. Some challenges including handover, delay, packet loss, jitter, fading and signal loss may be attributed to network congestion. Several studies have suggested increasing network resources as a way to cater for huge demands and reduce congestion in the network, while others suggest optimizing the available resources. In line with the optimization approach, a solution to improving video transmission in IEEE 802.11 networks is discussed that uses the Single-Queue Priority Scheduler (SQPS) to rearrange video frames according to their importance. In the presented simulation performed using the OPNET 14.5 modeler, an MPEG video (trace file) was rearranged by assigning weights to the video frames I, B and P, which, were then prioritized and arranged in a single queue for transmission. A parameter (Sn) was deduced from three metrics- deadline, priority and cost and used to actively arrange the video trace or frames from the lowest to the highest. The results show that the implementation of the SQPS algorithm improves the transmission of video in Wireless Local Area Network as the buffer-overflow loss is reduced from 22.8% to 8% of the total load, while, the Packet Loss Ratio is reduced from about 61% to 34%.