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Blockchain versus IOTA Tangle

16.2.4.4  Business Layer

This is specific to the architecture in Figure 16.7. This layer does more housekeeping

in the IoT system, where it manages the user’s application and data privacy, business

and profit models, and so on.

16.2.4.5  Processing Layer

This is the middleware layer. The processing includes data storage functions employ­

ing the use of databases and data analytics using technologies like edge, fog and

cloud computing, big data, etc. Third-party vendors frequently provide this layer’s

functions.

16.2.4.6  Transport Layer

The role of this layer, as the name implies, is to transfer data from the sensors at the

perception layer to be processed at the processing layer using network layer functions.

Bansal and Rana (2017) present a six-layer architecture similar to Figure 16.7. It

only differs in the inclusion of a coding layer, which they say provides identification

of objects of interest. The layer assigns unique IDs to each object to make it identifi­

able in the network.

16.2.4.7  Device Capability Exposure (DCE)

This is defined as a functional entity to manage the connected IoT devices in an IoT

area network, to expose the capabilities of the connected IoT devices to IoT applica­

tions, and to support the IoT applications to access the exposed device capabilities

(Zhao and Johnson, 2021). This reference model is shown in Figure 16.7.

FIGURE 16.7  Summary of IoT applications connectivity solutions. (From Behr, A., et al.,

Behr Technologies, 2020, https://behrtech​.com​/solutions/)