# Linked IoT

## Aim:

* By using Linked-Data and the web-standard semantic interoperability should be achieved
* The goal is to demonstrate how already existing standards of the Linked-Data can be used for IoT
* To reach the largest possible target audience, everything should be easily implemented (and as cheap as possible)
* Throughout a modular setting it should be possible for everybody to use their own components
* An extensive documentation should make it as easy as possible for the target audience to get started

## Problem:

* Linked Data has already proven its feasibility as instrument for connection and integration of data in the web
* With Linked Data it is possible to semantically combine structured data in order to describe their relationship
* At the moment it is difficult to bundle the different ways of broadcasting of each sensor and connect them with each other
* The different sensors can be addressed only with great effort but it’s impossible at the moment to process unknown structures and types of sensor independently 
* With the use of Constrained Devices their individual limitation has to be considered 

## Approach of solution:

* To make the modular setting possible, a library with abstract classes was built which can imported in the own project and run in Arduino 
* The context which is used in the JSON-LD, is saved on the gateway
* The bridge is working as operator in order to use the consistent web-standards for the broadcast
* With a web interface the sensor’s initialisation and broadcasting-configuration is enabled
* The linking between sensor and gateway is implemented throughout a web standard
* The bandwidth of the original payload (broadcast of the sensor’s data) is reduced through the transfer of the context at the linking
* The bridge is requesting the needed context at the gateway when broadcasting the sensor-data und is publishing the sensor’s value to the topic