## 3 Materials and Methods
### Phase 1: Assess the Potential and Maturity of IoT Solution Implementation
#### 3.1.1 Definition of the Stratified Sample of Agro-Food Companies  
The initial stage included the following methodological tasks:  
* Limit of the sample of agro-food companies for questioning;
* Creation of an \"Alternative Business Exchange\", in order to ensure, in due time, eventual failures/possibility of refusing to answer and/or last-minute impossibilities/imponderables of the pre-selected sample, even after due diligence of (re)confirmation;
* Survey and validation of e-mail contacts from the group of companies in the agro-food sector, in order to guarantee a sample with validated responses from at least 21 companies in the central region of Portugal. As the cluster of agro-industrial organizations of the central region in Portugal, Inov-Cluster's associates were potential companies for this part of the study [48], which was also in line with IOTEC project objectives. The contact list was analyzed, and after starting \begin{table}
\begin{tabular}{l l} \hline \hline
**Barriers** & **Brief Description** \\ \hline \multirow{4}{*}{(Cyber)security} & Operational risks are related to natural causes, such as animal attacks, rain, lightning, or even regular maintenance, could cause stoppage at a farm. \\  & Additionally, hacker attacks are linked to accessing sensitive information, \\  & hijacking cloud information or databases, or even blocking wireless signals. \\ \hline \multirow{4}{*}{Cost} & Implementation and operation are the main costs for IoT in agriculture. \\  & The implementation costs consist of hardware costs, such as IoT \\  & devices/sensors, base station infrastructure, and gateways. Furthermore, \\  & running costs include an uninterrupted subscription for the management \\  & of IoT devices, the exchange of information among other services, and \\  & centralized services that provide information/data collection. \\ \hline \multirow{4}{*}{Lack of knowledge} & Most farmers are uneducated in IoT, which creates a great barrier to \\  & understanding how technology could contribute to improve production. \\ \cline{1-1}  & Furthermore, it increases the costs of training to qualify people to use IoT \\ \cline{1-1}  & on their farms. \\ \hline \multirow{2}{*}{Interoperability} & Several IoT devices, standards and protocols are necessary to enable \\ \cline{1-1}  & communication between devices from different manufacturers. \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Brief description of main IoT challenges (adapted from [4; 11; 46]). the survey it was verified that some contacts no longer corresponded to the initial phone numbers and some of the initially contacted companies were closed. Notwithstanding these constraints, the information provided, associated with the adopted survey method, enabled an important methodological advance, namely allowing the survey to be directed to all companies that fell into the desired category and whose headquarters were located in the central region of Portugal. These options increased the likelihood of obtaining more favorable response rates and guaranteed representativeness in the sampling process. Figure 2 shows the percentage of small businesses in the subsector of the agro-food segment surveyed in the central region of Portugal. It was verified that most of the companies that were made available to collaborate in the characterization study belonged to the dairy sector, followed by the olive oil and honey sectors. Additionally, information about company sizes is shown in Figure 3. Half of the companies surveyed were micro-enterprises with fewer than five employees, with 40% of the companies being from the small business category. Only 10% of companies surveyed already had a size, considering the number of workers, which corresponded to a medium-sized company. This result highlights the reality of the agro-food industry, not only in the central region, but also in the whole country, which is composed mainly of micro and small enterprises, many of them being family businesses.