Digital Twin Architecture and Standards
Figure 2: Digital Twin Context Diagrams 13
connectivity is not reliable, configured digital
twin duplicates are deployed in adjacent
Industrial IoT tiers and bi-directionally
synchronized according to filter criteria
defined by the digital twin owner. A Digital
twin instance takes on the same policies
configured in the app store regardless of
which tier the replica resides in. The data
content in a replica may become stale over
time until the next synchronization but still
provide reliable, error-free data access for
local applications.
The interaction APIs are realized with
appropriate technology available in the tier.
Digital twin implementations might be
deployed using an app store like those for
mobile computing. The app store content is
replicated in each Industrial IoT tier and
enables direct access for third party
participation in the common ecosystem. App
store transactions in a disconnected tier are
journaled and replicated to other tiers when
communication is re-established.
Each digital twin deployment can have a
different information model allowing for
diversity in data representation and
relationships. This parallels the trend in
microservices where every service has a
unique set of programming interfaces, and
applications must know how to use them. In
a similar way, the digital twin information
model API enables discovery and
classification of types, properties and
instances.
Each digital twin serves as a publish and
subscribe hub in its tier, enabling event
driven application development using the
Model-View-Controller (MVC) pattern for
services. Any data exchange operation on
the digital twin generates a corresponding
notification published to all subscribed
clients for that event. Subscribers can use
these events to exercise digital twin CRUD
operations based on the metadata content
of an event.
Digital twins connect to applications and to
each other. To address conditions where
13
Malakuti, S., Ganz, C., Schlake, J., Harper, K.E., Digital Twin: An Enabler of New Business Models, Automation (2019).
IIC Journal of Innovation
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