Version Age of Information with Contact Mobility in Gossip Networks

2025-09-18

AI Summary

This paper investigates the impact of contact mobility on information freshness in gossip networks, focusing on minimizing Version Age-of-Information (VAoI)—the generational gap between a node’s local copy and the source’s latest version. We propose a hybrid update mechanism integrating passive epidemic dissemination with active node mobility, and develop a stochastic hybrid system model to characterize VAoI dynamics. Through theoretical analysis and extensive simulations, we quantify VAoI evolution across diverse topologies—including disconnected, sparse, and fully connected networks—and varying network scales. Our key finding is that contact mobility significantly reduces average VAoI, especially under extreme connectivity conditions. Furthermore, we formulate a trade-off optimization framework balancing mobility cost against information timeliness, enabling principled design of state synchronization protocols in mobile edge networks. This work establishes a novel paradigm for freshness-aware distributed coordination in dynamic, resource-constrained environments.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Constraint Satisfaction and Optimization: Distributed CSP/Optimization
• Multiagent Systems: Coordination and Collaboration

Application Category

• Social Networks and Social Media: Influence propagation, information diffusion, and the prediction on networks
• Systems and Infrastructure for Web, Mobile and WoT: Novel mobile and WoT systems, and system-of-systems
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs

Abstract

A gossip network is considered in which a source node updates its status while other nodes in the network aim at keeping track of it as it varies over time. Information gets disseminated by the source sending status updates to the nodes, and the nodes gossiping with each other. In addition, the nodes in the network are mobile, and can move to other nodes to get information, which we term contact mobility. The goal for the nodes is to remain as fresh as possible, i.e., to have the same information as the source's. To evaluate the freshness of information, we use the Version Age-of-Information (VAoI) metric, defined as the difference between the version of information available at a given node and that at the source. We analyze the effect of contact mobility on information dissemination in the gossip network using a Stochastic Hybrid System (SHS) framework for different topologies and mobility scalings with increasing number of nodes. It is shown that with the presence of contact mobility the freshness of the network improves in both ends of the network connectivity spectrum: disconnected and fully connected gossip networks. We mathematically analyze the average version age scalings and validate our theoretical results via simulations. Finally, we incorporate the cost of mobility for the network by formulating and solving an optimization problem that minimizes a weighted sum of version age and mobility cost. Our results show that contact mobility, with optimized mobility cost, improves the average version age in the network.

Problem

• Analyzing contact mobility impact on gossip network information freshness
• Studying Version Age-of-Information scaling with mobile nodes
• Optimizing mobility cost versus information freshness tradeoff

Innovation

• Contact mobility enhances information freshness
• Stochastic Hybrid System models network dynamics
• Optimization balances version age and mobility cost