DOCSIS performance evaluation: piggybacking versus concatenation

ABSTRACT

Demand for high-speed internet access is growing rapidly and new technologies have been developed to supply broadband access to homes and small businesses. One of these technologies, DOCSIS, delivers high-speed internet connections through existing cable television service. While many factors affect performance, an evaluation of the process by which cable modems request upstream bandwidth has not been studied under realistic web traffic conditions. Our study uses the network simulator ns along with our own DOCSIS extension to model these conditions. We studied the DOCSIS protocol, looking specifically at the performance effects of two enhancements to the bandwidth request mechanisms: piggybacking and concatenation. Our results show that piggybacking alone is the most effective method for enhancing the overall performance of DOCSIS.

REFERENCES

• 1: H. Balakrishnan, V. Padmanabhan, S. Seshan, M. Stemm, and R. Katz, TCP Behavior of a Busy Internet Server: Analysis and Improvements, IEEE INFOCOM98, 1998.
• 2: Paul Barford , Mark Crovella, Generating representative Web workloads for network and server performance evaluation, Proceedings of the 1998 ACM SIGMETRICS joint international conference on Measurement and modeling of computer systems, p.151-160, June 22-26, 1998, Madison, Wisconsin, United States
• 3: Cable Television Laboratories, Inc., Data-Over-Cable Service Interface Specifications: DOCSIS 2.0, Radio Frequency Interface Specifications, 1999-2003.
• 4: S. Cho, S. Park, and J. Kim, Performance Evaluation of the DOCSIS 1.1 MAC Protocol According to the Structure of a MAP Message, ICC 2001, Helsinki, Finland, June, 2001.
• 5: O. Elloumi, N. Golmie, H. Afifi, and D. Su, A Study of TCP Dynamics over HFC Networks, 1997.
• 6: C. Godsay, Upstream Performance Whitepaper, University Of New Hampshire, InterOperability Laboratory DOCSIS Consortium, 2003.
• 7: N. Golmie, F. Mouveaux, and D. Su, A Comparison of MAC Protocols for Hybrid Fiber/Coax Networks: IEEE 802.14 vs. MCNS, Proceedings of the 16th International Conference on Communications, Vancouver, Canada, June, 1999.
• 8: N. Golmie, Y. Saintillan, and D. H. Su, A Review of Contention Resolution Algorithms for IEEE 802.14 Networks, IEEE Communications Surveys, first quarter 1999.
• 9: V. Licea, A Comparison of the DVB/DAVIC, DOCSIS and IEEE 802.14 Cable Modem Specifications, IEEE 2000 ICC, May 2000.
• 10: Y. Lin, C. Huang, and W. Yin, Allocation and Scheduling Algorithms for IEEE 802.14 and MCNS in Hybrid Fiber Coaxial Networks, IEEE Transactions On Broadcasting, Vol. 44, No. 4, December 1998.
• 11: Y. Lin, W. Yin, and C. Huang, An Investigation into HFC MAC Protocols: Mechanisms, Implementation, and Research Issues, IEEE Communications Surveys, third quarter 2000.
• 12: J. Martin and N. Shrivastav, Modeling the DOCSIS 1.1/2.0 MAC Protocol, Proceedings of the 2003 International Conference on Computer Communications and Networks", Dallas TX, October 2003.
• 13: J. Mogul, Observing TCP Dynamics in Real Networks, Technical Report, Digital Western Lab, April 1992.
• 14: P. Tzerefos, V. Sdralia, C. Smythe and S. Cvetkovic, Delivery of Low Bit Rate Isochronous Streams Over DOCSIS 1.0 Cable Television Protocol, IEEE Transactions on Broadcasting, Vol. 45, No. 2, June 1999.
• 15: N. Shrivastav, A Network Simulator Model of the DOCSIS Protocol and a Solution to the Bandwidth-hog Problem in the Cable Networks, Masters Thesis, North Carolina State University, 2003.

INDEX TERMS

Primary Classification:
  C. Computer Systems Organization
  C.2 COMPUTER-COMMUNICATION NETWORKS
      C.2.5 Local and Wide-Area Networks

General Terms:
Measurement, Performance

Keywords:
DOCSIS, TCP performance, broadband access, cable networks, data over cable