AstroTimer: Rethinking Non-Access Stratum Timers in LEO Constellations

2026-01-23

AI Summary

This work addresses the inadequacy of existing 3GPP Non-Access Stratum (NAS) timers in low Earth orbit (LEO) satellite networks, where high topological dynamics, variable propagation delays, and stringent onboard resource constraints often trigger signaling storms and degrade efficiency. To overcome these challenges, we propose AstroTimer—the first lightweight, adaptive NAS timer framework tailored for LEO constellations. AstroTimer leverages LEO-specific parameters, including link dynamics, processing latency, and network element deployment locations, to derive a closed-form analytical model coupled with a lightweight optimization algorithm, enabling real-time adaptive configuration of watchdog and backoff timers. Simulation results demonstrate that, compared to the default 3GPP settings, AstroTimer significantly reduces registration latency, retry attempts, and terminal energy consumption while effectively mitigating signaling overload, offering a deployable and efficient solution for non-terrestrial 5G/6G networks.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Search and Optimization: Algorithm Configuration
• Multiagent Systems: Agent Communication

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• Graph Algorithms and Modeling for the Web: Algorithms and analysis for heterogeneous, signed, attributed, multi-relational, temporal, higher-order, and annotated Web-related graphs
• Search and Retrieval-Augmented AI: Agentic search

Abstract

Low-Earth Orbit (LEO) constellations expand 5G coverage to remote regions but differ fundamentally from terrestrial networks due to rapidly changing topologies, fluctuating delays, and constrained onboard resources. Existing 3GPP Non-Access Stratum (NAS) timers, inherited from terrestrial and geostationary (GEO) or medium Earth orbit (MEO) systems, fail to accommodate these dynamics, leading to signaling storms and inefficiency. This paper introduces AstroTimer, a lightweight, adaptive framework for sizing NAS timers based on LEO-specific parameters such as link variability, processing delays, and network-function placement. AstroTimer derives a closed-form timer model with low computational cost and optimizes both watchdog and backoff timers for the 5G registration procedure. Simulation results demonstrate that AstroTimer significantly reduces registration time, retry frequency, and user equipment (UE) energy consumption compared to 3GPP defaults, while preventing signaling overloads. The proposed approach provides an operator-ready foundation for reliable, efficient, and scalable non-terrestrial 5G/6G deployments.

Problem

• LEO constellations
• Non-Access Stratum (NAS) timers
• signaling storms
• 5G non-terrestrial networks
• timer inefficiency

Innovation

• LEO constellations
• NAS timers
• adaptive timing
• signaling optimization
• 5G non-terrestrial networks