## 5 Security and Privacy Threat Modelling
### Threat Modelling of Single User Single AMRSys with IoT  
If the robotic system aims to support and provide independent living to the older person in a true sense, then it needs to learn about every activity and the behaviour of the person under its roof. To provide the best ambient living environment, the robot can regulate, control, and manage the environment through the IoT systems connected to the thermostat, ventilation, lighting, window screening, heating, etc. It can monitor the health  
Figure 3: Threat Modelling of Single User AMRSys.  
condition of the user through smart healthcare devices. It can also control and monitor the user activity and manage medication e.g., reminding what medicine to take when, as shown in Figure 4. The threat increases during the integration of the IoT in the assistive robotic system. In this IoT and robotic framework, during the interaction and integration of the IoT devices, the system should make sure that the channel is secure, keys updated, and that the IoT devices are authenticated. Moreover, no default configuration and default password should be used forever, a malicious device should be detected and replaced, and so on, as these are some of the key security concerns in IoT systems. The IoT devices and their data should be reliable, dependable, and trustable. Otherwise, an incorrect decision could be taken, inappropriate action could be made, and moreover, wrong information could be collected about the user, their health, their environment, and so on. In addition, unless security measures are in place, IoT data collected about the user and their habitat by the robot could be easily leaked to any third party and the user's privacy compromised. Integrating IoT would optimise the decision-making process, but it should not overload the computational power of the robotic system. Therefore, a fog computing approach should be integrated to filter, aggregate, control, and verify the IoT data before feeding it into the robotic system, so that only meaningful information is fed to the robotic system.  
The security concerns in IoT are numerous and varied, there are many security challenges, and among them, the key challenges include securing resource constrained devices, authenticating and authorising battery-powered devices, and managing bugs and updates. In addition, securing the communication channel, secure integration with other systems, detecting and preventing incidents and vulnerabilities, predicting and pre-empting security issues, and ensuring data privacy and data integrity are vital [67]. Since the IoT system would be dealing with personal preference data, personal activity data, and the user's wellbeing data, it is sensitive in nature. Integrating the vulnerable IoT system with the assistive robotic system should not compromise users' data security and the user's data privacy. Moreover, the robotic system should be responsible for secure storage, key management, authentication, authorisation, and overall information management to preserve users' privacy and to protect itself from cyber-attacks, to safeguard its functionality, its OS, the attached data-generating sensors, storage, and its communication with the user.