" IEEE Trans. Inform. [48] G. Ungerboeck. "Channel coding outputs and its applications," Proc. Theory, vol. 45, pp. 399-431, March with multilevel/phase signals," IEEE GLOBECOM, vol. 3, pp. 1680- 1999. Trans. Inform. Theory, vol. 28, pp. 1686, Dallas, Texas, November [36] M. MacWilliams and N. Sloane. The 55-67, January 1982. 1989. Theory of Error-Correcting Codes, [49] N. Wiberg, H.-A. Loeliger, and [26] J. Jiang and K. Narayanan. "Iterative Karlin, North-Holland, 1992. R. Kötter. "Codes and iterative soft decoding of Reed-Solomon [37] J. Pearl. "Fusion, propagation, and decoding on general graphs," Eur. codes," IEEE Commun. Letters, structuring in belief networks," Trans. Telecommun., vol. 6, pp. vol. 8, pp. 244-246, April 2004. Artificial Intell. vol. 29, pp. 241-288, 513-525, September-October 1995. [27] H. Jin, A. Khandekar, and R. 1986. [50] S. Wicker. Error Control Systems for McEliece. "Irregular repeat- [38] J. G. Proakis and M. Salehi. Digital Communication and Storage, accumulate codes," Proc. 2nd Int. Communication Systems and Prentice-Hall, New Jersey, 1995. Symposium. Turbo Codes, pp. 1-8, Engineering, Prentice-Hall, New Brest, France, September 2000. Jersey, 2002. Chapter 3.5 Network adaptive media transport Mark Kalman and Bernd Girod 3.5.1 Introduction Unless firewalls force them to, streaming media sys- items do not rely on TCP but implement their own, ap- Internet packet delivery is characterized by variations in plication-layer transport mechanisms. This allows for throughput, delay, and loss, which can severely affect protocols that are both network adaptive and media the quality of real-time media. The challenge is to maxi- aware. A transport protocol may determine, for example, mize the quality of audio or video at the receiver, while when to retransmit packets for error control and when to simultaneously meeting bit-rate limitations and satisfying drop packets to avoid network congestion. If the protocol latency constraints. For the best end-to-end performance, takes into consideration the