## 3 IoT Standards and Protocols for Precision Agriculture
### IoT Standards for Precision Agriculture (Rq1)
#### 3.1.2 Analysed IoT Standards  
The state of the art in standards offers numerous solutions that provide a comprehensive framework for communication between IoT devices while meeting the identified requirements [39]. In this research, an analysis of these solutions was performed, evaluating them based on market adoption, origin, and requirements for agriculture. The key features of the analysed IoT standards are summarised in Table 2. In relation to the requirements for precision agriculture, the analysed IoT standards offer several complementary features. IPSO stands out for its light data flow and simplicity, making it ideal for low-power devices  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Application** & **IoT Standard** \\ \cline{2-3}  & **HTTP MQTT** \\ \hline
**Transport** & TCP UDP \\ \hline
**Internet** & IPV4/V6 6 LoWPAN \\ \hline \multirow{2}{*}{**Network access**} & SigFox LoRaWAN \\ \cline{2-3}  & Device \\ \hline \hline \end{tabular}
\end{table}
Table 1: IoT standards within the TCP/IP stack.  
in remote environments. Haystack, due to the flexibility of user-defined tags, is highly adaptable but can be complex to configure. OCF combines advanced functionality with good simplicity, offering a balanced solution for more interactive applications. Sensor-Things, with its native support for geolocation and various data types, is particularly well suited to complex scenarios with advanced analysis needs, although it may be overkill for simpler applications. The choice of standard will therefore depend on the specific context and implementation requirements.  
IP for Smart Objects (IPSO)  
The goal of IPSO is to establish a common design model and data model capable of providing high-level interoperability between sensors and software applications for the IoT [43]. In the IPSO standard, the structure representing the object includes a definition of the object type and a collection of resources formally named by the standard. Each resource represents a simple value that describes a specific function of the object. Objects and resources are mapped through URI paths, with each URI uniquely identifying an object [44]. The structure is composed of three 16-bit unsigned integers separated by the character \"/\" in the following form:  
\[ObjectID/InstanceID/ResourceID\]  
In IPSO, objects are typed containers defining the semantic type of their instances, which hold resources representing observable properties. For example, a temperature sensor URI like \"3303/0/5700\" uses \"3303\" as the object ID, \"0\" as the instance ID, and \"700\" as the resource ID for the sensor value. Objects represent single points of measurement or control, while resources define specific properties like current, minimum, or maximum values. Semantic interoperability is achieved through standardized object and resource identifiers, enabling consistent representation of data, such as temperature readings or limits. IPSO defines over 50 smart object types, including sensors (e.g., temperature, humidity, barometers), input/output devices (digital, analog, and generic I/O), presence detectors, accelerometers, power monitors, load and lighting controls, actuation devices, and set points.