Improving Upstream Efficiency (2021)

By Karthik Sundaresan, Tom Williams, Sheldon Webster, Alberto Campos & Doug Jones, CableLabs

Cable operators are facing an unprecedented increase in upstream traffic usage because of the shift to working/schooling from home, and the reliability, capacity, and efficiency of the upstream is top of mind for all operators. This paper is focused on improving the efficiency of the DOCSIS upstream (DOCSIS3.0 SC-QAM and DOCSIS 3.1 OFDMA) channels. The paper will document some of the upstream engineering problems seen by operators and make robust recommendations on how improve those situations. There are thousands of upstream parameter settings and control knobs available to an operator and much of the time operators leave those settings at their default values. This paper will investigate areas (for SC-QAM & OFDMA) such as mini slot size, FEC, Cyclic Prefix, FFT size, frame size, pilot patterns, channel size, guard bands, profile definition, CMTS settings for changing IUCs, etc., and make recommendations on each of those parameters and settings. This paper will also explore configuration file service parameters for a cable modem (CM) and make recommendations for better performance on the upstream. Ultimately, this paper will help operators understand optimized upstream configurations and settings for production deployments.

This paper assumes some background understanding of both DOCSIS 3.0 and DOCSIS 3.1 upstream technologies. Here we try to provide an understanding of different upstream channel parameters (which an operator can tweak) and then the pros and cons of choosing different values for that parameter. Based on these tradeoffs we make recommendations on optimal values for each of these channel parameters or network configurations.

By clicking the "Download Paper" button, you are agreeing to our terms and conditions.

Similar Papers

OFDMA Predistortion Coefficient and OFDM Channel Estimation Decoding and Analysis
By Tom Williams, Alberto Campos, Lin Cheng, James Lin, Jason Rupe & Jay Zhu, CableLabs
2021
Upstream OFDMA Anomaly Detection and Triaging
By Jay Zhu & Karthik Sundaresan, CableLabs
2021
Improving Power Supply Efficiency
By Tom S. Osterman, Alpha Technologies Inc.
1987
Accurately Estimating D3.1 Channel Capacity
By Karthik Sundaresan, CableLabs
2017
The Scheduler and the Tap: The Odd Infrastructure Couple
By L. Alberto Campos, Lin Cheng, Zhensheng (Steve) Jia, Jing Wang & Chris Stengrim, CableLabs
2021
FDX & D3.1 Capacity Scenarios
By Karthik Sundaresan, CableLabs
2018
DOCSIS 3.1 Configurations for HFC and RFoG
By Doug Jones, CableLabs
2017
CableLabs' Ghost Canceller Testing Project
By Tom Williams, Cable Television Laboratories, Inc.
1992
Field Experiences with US OFDMA and Using US Profile Management
By Karthik Sundaresan & Jay Zhu, CableLabs; João Pedro Fernandes, NOS
2020
DOCSIS 4.0 Technology Realizing Multigigabit Symmetric Services
By Doug Jones, CableLabs
2019
More Results >>