FAST: A Channel Access Protocol for Wireless Video (and Non-Video) Traffc Sohraab Soltani Intelligent Automation, Inc. Rockville, Maryland 20855 Email: ssoltani@i-a-i.com Hassan Aqeel Khan, and Hayder Radha Department of Electrical and Computer Engineering Michigan State University Abstrct-This paper presents the design of a new paradigm for a content-aware wireless MAC layer that is optimized for wireless video (frst and foremost) while targeting fairness and stability among competing video trafc, and among video and non-video traffc. Hence, we refer to the proposed MAC frame work as the FAST (Fair And STable) protocol. FAST employs two parameters for each packet, a qualit value and a time-to live value. Based on these parameters, FAST is designed on a muIticlass priority queuing system that classifes the incoming trafc according to the content of each trafc fow and further identifes different priorities within each video content. We develop analytical frameworks to formulate channel allocation based on video/non-video fairness and video stability require ments as a joint bandwidth maximization and scheduling opti mization problem. We incorporate these frameworks to design and simulate a content-aware channel access mechanism, which utilizes video trafc content classifcations and users demand in conjunction with stability and fairness requirements at the MAC layer to allocate wireless channels to individual wireless users. Our simulation results show that FAST provides signifcant improvements in packet-loss-ratio, delay, overall fairness, and stability parameters when compared with leading access control mechanisms over 4GITE environment. I. INTRODUCTION It has been well documented by many studies that realtime video is emerging as the most dominant traffc delivered over the Internet, in general, and wireless networks in particular. Many studies also predict that this trend of video trafc predominance will continue to grow many years and probably decades into the future. Real-time Internet video will reach 62% of consumer Internet trafc by the end of 2015. Further more, consumers are becoming more demanding in terms of video quality. It is predicted that high-defnition Internet video will represent 77% of video-on-demand by 2015. This explosive growth in multimedia Internet applications is primarily a result of the rapid advances in high speed wireless access and the remarkable emergence of mobile applications allowing users to launch these applications using 4G/LTE networks. The CISCO visual networking index predicts that mobile data traffc will grow 26 times between 2010 and 2015, to 6.3 exabyte - a billion gigabytes - per month; and more importantly, mobile video will be 66% of mobile trafc by 2015. These and other staggering statistics about Internet and wireless video emphasize the urgent need for new paradigms for the support and delivery of wireless video. The 978-1-4673-2447-2/12/$3l.00 © 2012 IEEE East Lansing, Michigan 48824 Email: hkhan, radha@egr.msu.edu limited bandwidth of wireless and mobile networks and the tremendous growth in wireless and mobile IP trafc further exacerbate the need for new solutions that can handle video trafc to heterogeneous wireless devices. This paper presents the design of a new paradigm for a content-aware wireless MAC layer that is optimized for wireless video (frst and foremost) while targeting fairness and stability among competing video trafc, and among video and non-video trafc. Hence, we refer to the proposed MAC famework as the FAST (Fair And STable) protocol. The proposed FAST MAC targets intra-stability and inter-fairness objectives among competing trafc fows at the base station. It ensures intra-stability for each video user by considering a time-ta-live parameter for the video packets to acquire precedence-access to wireless channels within the end-to-end deadline of the time-sensitive video application. This ensures high-quality and smooth video playback at the end-user. To that end, FAST periodically computes the average queuing delay of each video fow (at the base station) and determines the minimum required bandwidth rate for that fow (based on the time-to-live parameter) to ensure intra-stability. The inter-fairness objective of the FAST MAC is to deter lnine a fair channel access distribution among competing real time video and non-video users. We develop a content aware channel access mechanism (at the base station) to identify and prioritize traffc fows based on the video packet qualit parameter and the non-video contents. The proposed FAST protocol is content-aware in the sense that it even identifes priorities within each video fow with respect to the importance of the video packet quality. FAST then partitions the available channel and allocates subchannels to each video/non-video pri ority fow. FAST formulates the channel access mechanism as a joint bandwidth maximization and scheduling optimization problem. The proposed MAC is designed based on a multiclass priority queuing system that classifes and manages the trafc demand by users in prioritized fashion according to the content of each traffc fow and further identifes different priorities within each video content. In summary, the contribution of this paper is as follows: • We develop an analytical model for the average waiting time of each priority video and non-video fow at the FAST MAC layer using multiclass priority queuing sys tem.