Table of Contents - Y.4239 (11/2025) - Reference model for integrating virtual and physical worlds through digital twins in the metaverse

1	Scope
2	References
3	Definitions
	3.1	Terms defined elsewhere
	3.2	Terms defined in this Recommendation
4	Abbreviations and acronyms
5	Conventions
6	Reference model
7	Functions of metaverse system
	7.1	General
	7.2	General functions
	7.3	Physical integration functions
	7.4	Third-party service integration functions
8	Functions of digital twin system
	8.1	General
	8.2	General functions
	8.3	Virtual integration functions
9	Functions of third-party service system
	9.1	General
	9.2	General functions
	9.3	Metaverse integration functions
10	Functions of integration enabler
	10.1	General
	10.2	Services integration functions
	10.3	Digital twin integration functions
Bibliography