3 Engineering IoT Networks
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HART Message over IP Backbone
Network and
Security Manager
Process
Automation
Controller 1
Gateway 1
Process
Automation
Controller 2
Gateway 2
Plant
Automation Network
HART over IP
Access
Point
Field
Device
Field
Device
Field
Device
Router
Device
Zone A
Access
Point
Field
Device
Field
Device
Field
Device
Router
Device
Field
Device
Zone B
Access
Point
Field
Device
Field
Device
Field
Device
Router
Device
Zone C
Fig. 3.16 Example of WirelessHART architecture using a single backbone to connect multiple
wireless zones
and beacon-based mode. Upper layers have been designed specifically for WirelessHART. The Network Layer is responsible for several functions, the most
important of which are routing and security within the mesh network. Whereas
the Data Link Layer moves packets between devices, the Network Layer moves
packets end-to-end within the wireless network. The Network Layer also includes
other features such as route tables and time tables. Route tables are used to route
communications along graphs. Time tables are used to allocate communication
bandwidth to specific services such as publishing data and transferring blocks of
data. Network Layer security provides end-to-end data integrity and privacy across