Packet Skipping and Network Coding for Delay-Sensitive Network Communication

TL;DR

This paper analyzes how packet skipping and network coding can improve timely message delivery in networks with delay constraints, providing models and performance comparisons for each approach and their combination.

Contribution

It introduces an analytical framework for evaluating packet skipping and network coding, including their joint effects, on delay-sensitive network communication performance.

Findings

Packet skipping improves goodput under certain threshold policies.

Network coding enhances packet delivery rates for deadline-constrained messages.

Combined approach offers insights into optimal strategies for delay-sensitive networks.

Abstract

We provide an analytical study of the impact of packet skipping and opportunistic network coding on the timely communication of messages through a single network element. In a first step, we consider a single-server queueing system with Poisson arrivals, exponential service times, and a single buffer position. Packets arriving at a network node have a fixed deadline before which they should reach the destination. To preserve server capacity, we introduce a thresholding policy, based on remaining time until deadline expiration, to decide whether to serve a packet or skip its service. The obtained goodput improvement of the system is derived, as well as the operating conditions under which thresholding can enhance performance. Subsequently, we focus our analysis on a system that supports network coding instead of thresholding. We characterize the impact of network coding at a router node on the delivery of packets associated with deadlines. We model the router node as a queueing system where packets arrive from two independent Poisson flows and undergo opportunistic coding operations. We obtain an exact expression for the goodput of the system and study the achievable gain. Finally, we provide an analytical model that considers both network coding and packet skipping, capturing their joint performance. A comparative analysis between the aforementioned approaches is provided.