DOI QR코드

DOI QR Code

Gateway Strategies for VoIP Traffic over Wireless Multihop Networks

  • Kim, Kyung-Tae (Mobile Systems Design Laboratory, Dept. of Electrical and Computer Engineering, Stony Brook University-SUNY) ;
  • Niculescu, Dragos (ETTI, University POLITEHNICA of Bucharest) ;
  • Hong, Sang-Jin (Mobile Systems Design Laboratory, Dept. of Electrical and Computer Engineering, Stony Brook University-SUNY)
  • Received : 2010.11.06
  • Accepted : 2010.12.04
  • Published : 2011.01.31

Abstract

When supporting both voice and TCP in a wireless multihop network, there are two conflicting goals: to protect the VoIP traffic, and to completely utilize the remaining capacity for TCP. We investigate the interaction between these two popular categories of traffic and find that conventional solution approaches, such as enhanced TCP variants, priority queues, bandwidth limitation, and traffic shaping do not always achieve the goals. TCP and VoIP traffic do not easily coexist because of TCP aggressiveness and data burstiness, and the (self-) interference nature of multihop traffic. We found that enhanced TCP variants fail to coexist with VoIP in the wireless multihop scenarios. Surprisingly, even priority schemes, including those built into the MAC such as RTS/CTS or 802.11e generally cannot protect voice, as they do not account for the interference outside communication range. We present VAGP (Voice Adaptive Gateway Pacer) - an adaptive bandwidth control algorithm at the access gateway that dynamically paces wired-to-wireless TCP data flows based on VoIP traffic status. VAGP continuously monitors the quality of VoIP flows at the gateway and controls the bandwidth used by TCP flows before entering the wireless multihop. To also maintain utilization and TCP performance, VAGP employs TCP specific mechanisms that suppress certain retransmissions across the wireless multihop. Compared to previous proposals for improving TCP over wireless multihop, we show that VAGP retains the end-to-end semantics of TCP, does not require modifications of endpoints, and works in a variety of conditions: different TCP variants, multiple flows, and internet delays, different patterns of interference, different multihop topologies, and different traffic patterns.

Keywords

References

  1. J. Li, C. Blake, D. S. J. De Couto, H. K. Lee and R. Morris, "Capacity of ad hoc wireless networks," in Proc. of 7th ACM International Conference Mobile Computing and Networking, pp. 61-69, 2001.
  2. K. Kim and S. Hong, "VoMESH: Voice over wireless MESH networks," in Proc. of IEEE Wireless Communications and Networking Conf., pp. 193-198, 2006.
  3. J. Yu, S. Choi, and J. Lee, "Enhancement of VoIP over IEEE 802.11 WLAN via dual queue strategy," in Proc. of ICC, pp. 3706-3711, 2004.
  4. W. Wang, S. C. Dovrolis, M. Murray, and K. Claffy, "Solutions to performance problems in voip over 802.11 wireless lan," IEEE Trans. on Vehicle Technology, vol. 54, no. 1, pp. 366-384. Jan. 2005.
  5. R. Prasad, C. Dovrolis, M. Murray, and K. Claffy, "Bandwidth estimation: metrics, measurement techniques, and tools," IEEE Network, vol.17, no. 6, pp.27-35, Nov.-Dec. 2003.
  6. K. Xu, K. Tang, R. Bargrodia, M. Gerla, and M. Bereschinsky, "Adaptive bandwidth management and qos provisioning in large scale ad hoc networks," in Proc. of IEEE Military Communications Conf., vol. 2, pp. 1018- 1023, 2003.
  7. F. Y. Li, M. Haugea, A. Hafslund, L. Kure, and P. Spilling, "Estimating residual bandwidth in 802.11-based ad hoc networks: An empirical approach," in Proc. of 7th Int. Symposium on Wireless Personal Multimedia Communications (WPMC '04), vol. 7, no. 10, pp. 1228-1241, 2004.
  8. A. Bakre and B. R. Badrinath, "I-TCP: indirect TCP for mobile hosts," in Proc. of 15th Int. Conf. on Distributed Computing Systems, pp. 136-143, 1995.
  9. H. Balakrishnan, S. Seshan, E. Amir, and R. H. Katz, "Improving TCP/IP performance over wireless networks," in Proc. of 1st Int. Conf. on Mobile Computing and Networking, pp. 2-11, 1995.
  10. H. Balakrishnan, S. Seshan, E. Amir, and R. H. Katz, "Improving TCP/IP performance over wireless networks," in Proc. of 1st Int. Conf. on Mobile Computing and Networking, pp. 2-11, 1995.
  11. H.-Y. Wei, S.-C. Tsao, and Y.-D. Lin, "On shaping TCP traffic at edge gateways," in Proc. of 4th GLOBECOM, vol.2, no.3, pp.833-839, 2004.
  12. H. Fei and B. Yu, "Performance evaluation of wireless mesh networks with self-similar traffic," in Proc. of Int. Conf. on Wireless Communications, Networking and Mobile Computing, pp.1697-1700, 2007.
  13. R. G. Cole and J. Rosenbluth, "Voice over IP performance monitoring," SIGCOMM Computer Communication Review, vol. 31, no. 2, pp. 9-24, April 2001.
  14. Z. Fu, P. Zerfos, H. Luo, S. Lu, L. Zhang, and M. Gerla, "The impact of multihop wireless channel on TCP throughput and loss," in Proc. of 22nd IEEE Int. Conf. on Computer Communications, vol. 3, pp. 1744-1753, 2003.
  15. S. Xu and T. Saadawi, "Does the IEEE 802.11 MAC protocol work well in multihop wireless ad hoc networks?," IEEE Communications Magazine, vol. 39, no. 6, pp. 130-137, Jun 2001.
  16. L. Xu and I. Rhee, "CUBIC: A new TCP-Friendly high-speed TCP variant," in Proc. of 3rd Int. Workshop on Protocols for Fast Long-Distance Networks, vol. 42, 2005.
  17. K. Tan, J. Song, Q. Zhang, and M. Sridharan, "A compound TCP approach for high-speed and long distance networks," in Proc. of 25th IEEE Int. Conf. on Computer Communications, pp. 1-12, 2006.
  18. Dragoş Niculescu, Interference map for 802.11 networks, Proceedings of the 7th ACM SIGCOMM conference on Internet measurement, pp. 339-350, October 24-26, 2007.
  19. K. Chen, Y. Xue, S. H. Shah, and K. Nahrstedt, "Understanding bandwidth-delay product in mobile ad hoc networks," Elsevier Computer Communications Special Issue on Protocol Engineering for Wired and Wireless Networks, vol.27, pp.923-934, 2003.
  20. Eddie Kohler, Robert Morris, Benjie Chen, John Jannotti, and M. Frans Kaashoek, "The Click modular router", ACM Transactions on Computer Systems, vol. 18, pp. 263-297, August 2000.