Abstract
A Wi-Fi broadcasting system is a kind of Mobile-TV system that transmits multimedia content over Wi-Fi networks. The specialty of the system is that it takes advantage of broadcast packets for streaming to be scalable to the number of users. However, the loss rate of broadcast packets is much higher than that of unicast ones because MAC layer retransmission is not applied on broadcast packets. To recover lost packets, a packet level Forward Error Correction (FEC) scheme is usually used in Wi-Fi broadcasting systems. But it introduces additional transmission overhead, which is usually proportional to the packet loss rate. So it is important to reduce the packet loss rate to build an efficient and reliable Wi-Fi broadcasting system. While past studies have considered only single-AP systems, our study focuses on a multi-AP system which is designed to cover a much larger area. We found a specific packet collision problem that increases packet loss rate significantly in a multi-AP system. It is caused by the simultaneous arrival and transmission of a broadcast packet at and by APs. We identify two scenarios of the collision that depend on the channel state at the time of packet arrival. We propose two collision avoidance methods to handle these scenarios: Broadcast Packet Scheduling Method (BPSM) and Adaptive Contention Window-Sizing Method(ACWSM). We implement both methods in our multi-AP Wi-Fi broadcasting system and verify their effectiveness through experiments.
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References
Alix 3 C2, http://pcengines.ch/alix3c2.htm
ANSI/IEEE Std 802.11, 1999 Edition, Part II: Wireless LAN Medium Access Control(MAC) and Physical Layer(PHY) Specifications, ISO/IEC 8802–11:1999 (E).
Bianchi G (2000) Performance Analysis of the IEEE 802.11 Distributed Coordination Function. IEEE Journal on Selected Areas in Communications 18(3):535–547
Chilamkurti N, Zeadally S, Soni R, Giambene G (2010) Wireless multimedia delivery over 802.11e with ross-layer optimization techniques. Multimed Tools Appl 47:189–205
Convertino, G., Oliva, S.L., (2006). Adaptive FEC for 802.11 Burst Losses Reduction, in MobiMedia '06: Proceedings of the 2nd international conference on Mobile Multimedia communications (pp. 1–5). New York, NY, USA: ACM.
Draft Supplement to IEEE Std 802.11 Medium Access Control Enhancement for Quality of Service(QoS), IEEE Std 802.11e/D3.1 July 2002.
Dujovne, D., Turletti, T., Multicast in 802.11 WLANs: an experimental study, ACM MSWim ‘06’.
EMP-8602 + S, http://www.engeniustech.com
Jaehyuk Choi and Kang G. Shin, QoS provisioning for large-scale multi-AP WLANs, Elsevier Ad-hoc networks, to be published March 2012.
Kim J, Jang H, Yun J, Bae B (2007) Design and Implementation of DMBonIP Gateway to Provide Internet Based DMB Service. IEEE Transaction on Consumer Electronics 53(1):120–123
Lin C-H, Shieh C-K, Naveen K (2008) A RED-FEC Mechanism for Video Transmission Over WLANs. IEEE TRANSACTIONS ON BROADCASTING 54(3):517–524
Ma, X., Chen, X., (2007). Saturation Performance of IEEE 802.11 Broadcast Networks, IEEE Communication Letters, Vol. 11
MadWiFi, http://madwifi.org.
Makharia, S., Raychaudhuri, D., Mingquan, Wn., (2008) Experimental Study on Wireless Multicast Scalability using Merged Hybrid ARQ with Staggered Adaptive FEC, World of Wireless, Mobile and Multimedia Networks(WoWMoM 2008), Newport Beach. CA, pp. 1–12
Munaretto, D., Scalia, L., Soni, T., Widmer J. (2009). Reliable Broadcast Streaming over 802.11 WLANs with Minimum Channel Usage, Computers and Communication, 2009. ISCC 2009. IEEE Symposium on, pp. 30–35.
Park K., Wang, W., (1998). AFEC: An adaptive forward error correction protocol for end-to-end transport of real-time traffic, in Proc. Computer Communications and Network, ICCCN1998, pp. 196–205
Takahata, K., Uchida, N., Shibata, Y., (2003). Packet error and frame rate controls for real time video stream over wireless LANs, in proc. Distributed Computing Systems Workshops, ICDCSW2003, pp. 594–599
van der Schaar M, Andreopoulos Y, Hu Z (2006) Optimized Scalable video Streaming over IEEE 802.11a/e HCCA Wireless Networks under Delay Constraints. IEEE Transaction on Mobile Computing 5(6):755–768
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This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2012-0001578)
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Kim, D.H., Kim, J.D. A collision avoidance scheme for the synchronized broadcast packets in a multi-AP Wi-Fi broadcasting system. Multimed Tools Appl 69, 643–659 (2014). https://doi.org/10.1007/s11042-012-1113-1
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DOI: https://doi.org/10.1007/s11042-012-1113-1