On the Value of Information in Status Update Systems

Area of Science:

• Information Theory
• Computer Science
• Cyber-Physical Systems

Background:

• The age of information (AoI) is a standard metric for information freshness.
• Existing AoI models assume all information packets have equal value.
• Cyber-physical systems often involve packets with inherent, time-sensitive value.

Purpose of the Study:

• To develop a novel framework for analyzing information freshness that incorporates the value of information (VoI).
• To investigate status update systems where packets have a defined value that decays over time.
• To derive analytical expressions for average sum VoI and packet VoI under various queuing disciplines.

Main Methods:

• Modeling status update systems with packets possessing initial values and deterministic deadlines.
• Defining two key metrics: sum VoI and packet VoI.
• Analyzing queuing disciplines considering potential value-service time dependencies.
• Deriving closed-form expressions for average VoI metrics.

Main Results:

• Closed-form expressions for average sum VoI and average packet VoI were derived.
• The study provides insights into how packet value decay impacts information freshness metrics.
• Numerical results illustrate VoI dynamics across different scenarios.

Conclusions:

• The proposed VoI framework offers a more nuanced approach to information freshness than traditional AoI.
• Understanding value decay is crucial for optimizing data delivery in time-sensitive applications.
• The derived expressions enable better system design for cyber-physical applications prioritizing information value.