The concept of digital twin (DT), which enables the creation of a
programmable, digital representation of physical systems, is expected to
revolutionize future industries and will lie at the heart of the vision of a
future smart society, namely, Society 5.0, in which high integration between
cyber (digital) and physical spaces is exploited to bring economic and societal
advancements. However, the success of such a DT-driven Society 5.0 requires a
synergistic convergence of artificial intelligence and networking technologies
into an integrated, programmable system that can coordinate networks of DTs to
effectively deliver diverse Society 5.0 services. Prior works remain restricted
to either qualitative study, simple analysis or software implementations of a
single DT, and thus, they cannot provide the highly synergistic integration of
digital and physical spaces as required by Society 5.0. In contrast, this paper
envisions a novel concept of an Internet of Federated Digital Twins (IoFDT)
that holistically integrates heterogeneous and physically separated DTs
representing different Society 5.0 services within a single framework and
system. For this concept of IoFDT, we first introduce a hierarchical
architecture that integrates federated DTs through horizontal and vertical
interactions, bridging the cyber and physical spaces to unlock new
possibilities. Then, we discuss the challenges of realizing IoFDT, highlighting
the intricacies across communication, computing, and AI-native networks while
also underscoring potential innovative solutions. Subsequently, we elaborate on
the importance of the implementation of a unified IoFDT platform that
integrates all technical components and orchestrates their interactions,
emphasizing the necessity of practical experimental platforms with a focus on
real-world applications in areas like smart mobility.

数字孪生、Society 5.0、互联网联合数字孪生、分层架构和 IoFDT 平台是本文的关键词，该文讨论了如何实现 IoFDT 概念，挑战和创新解决方案，并强调了一个统一的 IoFDT 平台的重要性与实际应用。