Packet reservation multiple access for multimedia traffic

Abstract

Packet reservation multiple access (PRMA) was designed for supporting only voice and data traffics. To investigate the performance of PRMA for video transmission, a modified version of PRMA is needed to be considered. In this paper, a modification to the PRMA protocol proposed for supporting video traffic was investigated using a computer simulation. A real video Imce fde from H.261 codec was used as a video traffic for simplification and accuracy in the simulation study. The simulation results show that the moditied scheme for supporting E261 video traffic could provide acceptable quality-of-service at a given number of video terminal in the system. Furthermore, the modifed PRMA could support simultaneously 28 voice terminals operating at 32 kbps. 28 data terminals generating data packets at a rate of 1200 bps. and one H.261 video terminal at the mean bit rate of 64 kbps, at the channel rate of 720 kbps in the system.

A Framework for Advanced Video Traces: Evaluating Visual Quality for Video Transmission Over Lossy Networks

“…When a frame loss occurs in a GoP, a summarization of the motion information across all affected frames of the GoP is computed. This can be accomplished by using (2), (5), (6), and 7, and averaging over all ((R + 2)L − 1) frames that suffer a quality degradation due to a P-frame loss at time instance t:…”

“…Conventional video traces characterize the video encoding, that is, they contain the size (in bits) of each encoded video frame and the corresponding visual quality (measured in PSNR) as well as some auxiliary information, such as frame type (I, P, or B) and timing information for the frame play-out. These video traces are available from public video trace libraries [3,4] and are widely used among networking researchers to test novel transport protocols for video, for example, network resource management mechanisms [5,6], as they allow for simulating the operation of networking and communications protocols without requiring actual videos. Instead of transmitting the actual bits representing the encoded video, only the number of bits is fed into the simulations.…”