The sixth generation of DOCSIS standard is currently under development for the provisioning of multi-Gbps services over cable networks. Building upon DOCSIS 3.1 (D3.1), DOCSIS 4.0 (D4) introduces several features including full-duplex transmission and extended-spectrum, which benefit from subcarrier-level OFDM modulation configurations to adapt to varying channel conditions. To exploit the full potential of D4, we propose a softwarized adaptive subcarrier modulation management framework. The optimization system consists of (i) a clustering mechanism that classifies CMs (Cable Modems) with a similar channel condition into the same group using a sparsified K-means algorithm and (ii) an efficient profile generation mechanism to balance achieved channel throughput and packet error rate within the same group. Then, we implement key elements of the softwarized system using a virtualized network function in our DOCSIS experimental testbed that enables the programmatic control of OFDM channels using D4 performance parameters. Our experimental results show that the proposed optimization function offers significant improvements in OFDM channel throughput over current industry management practices. Furthermore, we confirm via simulations that using a novel clustering algorithm for the classification of CM populations and a new bit-loading method measurably enhances channel performance in large-scale distributed deployment scenarios.

中文翻译：

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迈向可编程 DOCSIS 4.0 网络：OFDM 信道中的自适应调制


目前正在开发第六代 DOCSIS 标准，用于通过有线网络提供多 Gbps 服务。 DOCSIS 4.0 (D4) 以 DOCSIS 3.1 (D3.1) 为基础，引入了全双工传输和扩展频谱等多项功能，这些功能受益于子载波级 OFDM 调制配置，可适应不同的信道条件。为了充分发挥 D4 的潜力，我们提出了一种软件化的自适应子载波调制管理框架。该优化系统由以下部分组成：(i) 聚类机制，使用稀疏 K 均值算法将具有相似信道条件的 CM（电缆调制解调器）分类到同一组；以及 (ii) 高效的配置文件生成机制，以平衡所实现的信道吞吐量和数据包同一组内的错误率。然后，我们在 DOCSIS 实验测试台中使用虚拟化网络功能来实现软件化系统的关键要素，该测试台能够使用 D4 性能参数对 OFDM 通道进行编程控制。我们的实验结果表明，与当前的行业管理实践相比，所提出的优化函数显着提高了 OFDM 信道吞吐量。此外，我们通过模拟确认，使用一种新颖的聚类算法对 CM 群体进行分类，并采用一种新的比特加载方法可显着提高大规模分布式部署场景中的信道性能。