SKYCASTLE: Taming LEO Mobility to Facilitate Seamless and Low-latency Satellite Internet Services

TL;DR

This paper tackles the mobility management challenge in Integrated Space and Terrestrial Networks (ISTNs) where both users and network infrastructure (LEO satellites) are mobile. It proposes SKYCASTLE, a network-based global mobility management mechanism that uses distributed satellite anchors and an anchor manager to achieve convergence-free routing and dynamic anchor assignment, reducing disruption time and user-perceived latency. Through trace-driven simulations with real constellation data, SKYCASTLE demonstrates substantial improvements, including up to 55.8% more uninterrupted connectivity and up to 47.8% lower latency compared with existing MM schemes. The work highlights a practical path to reliable, low-latency global Internet services for mobile ISTN users such as those on aircraft or ships, by integrating satellite dynamics into mobility planning and routing.

Abstract

Emerging integrated space and terrestrial networks (ISTN) built upon low earth orbit (LEO) satellite constellations aim at providing planet-wide Internet services, not only for residential users, but also for mobile users (e.g., in airplane and cruise scenarios). Efficiently managing global mobility and keeping connections active for mobile users is critical for ISTN operators. However, our quantitative analysis identifies that existing mobility management (MM) schemes suffer from frequent connection interruptions and long latency in ISTN scenarios. The fundamental challenge stems from a unique characteristic of ISTNs: not only users are mobile, but also core network infrastructures (i.e., LEO satellites) are frequently changing their locations in the network. To facilitate seamless and low-latency satellite Internet services, this paper presents SKYCASTLE, a novel network-based global mobility management mechanism. SKYCASTLE incorporates two key techniques to address frequent connection interruptions in ISTNs. First, to reduce the interruption time, SKYCASTLE adopts distributed satellite anchors to track the location changes of mobile nodes, manage handovers and avoid routing convergence. Second, SKYCASTLE leverages an anchor manager to schedule MM functionalities at satellites to reduce deployment costs while guaranteeing low latency. Extensive evaluations combining real constellation information and mobile user trajectories show that: SKYCASTLE can improve up to 55.8% uninterrupted time and reduce 47.8% latency as compared to other existing MM solutions.

Figures (10)

• Figure 1: A typical architecture of ISTN.
• Figure 2: Basic principles for mobility management (MM).
• Figure 3: The design choices of deploying MM in ISTNs.
• Figure 4: Performance of applying anchors at GSs and satellites.
• Figure 5: Overview of SkyCastle.

Theorems & Definitions (6)

• Lemma 1
• proof
• Theorem 1
• proof
• Theorem 2
• proof