Mobile-Aware Scheduling for Low Latency Backhaul over DOCSIS

TL;DR

This paper explores latency reduction techniques for mobile backhaul over DOCSIS networks, focusing on coordinated scheduling to improve end-to-end latency, especially under congestion, and investigates the impact of HARQ failure through simulations.

Contribution

It introduces a coordinated scheduling method that reduces DOCSIS backhaul latency and demonstrates its effectiveness even with LTE protocol uncertainties.

Findings

Coordinated scheduling improves overall system latency.

Latency reduction is significant under network congestion.

HARQ failure impacts are mitigated by the proposed method.

Abstract

In this paper, we discuss latency reduction techniques for mobile backhaul over Data Over Cable Service Interface Specifications (DOCSIS) networks. When the latencies from both the wireless and the DOCSIS networks are added together, it can result in noticeable end-to-end system latency, particularly under network congestion. Previously, we proposed a method to improve upstream user-to-mobile core latency by coordinating the LTE and DOCSIS scheduling. The method reduces the impact on system latency from the DOCSIS network's request-grant-data loop, which is the main contributor of backhaul upstream latency. Since the method reduces latency on the DOCSIS data path, it will therefore improve performance of latency sensitive applications, particularly if TCP is used as the transport protocol, especially when the link is congested. In this paper, we investigate the effect of HARQ failure on system performance. Through simulation, we show that despite the uncertainty introduced by the LTE protocol, coordinated scheduling improves overall system latency.