5 Challenges and barriers of IoT
5.1 Challenges

Reliability

Reliability aims to increase the success rate of IoT service delivery. It has a close relationship with availability as by reliability, we guarantee the availability of information and services over time. Reliability is even more critical and has more stringent requirements when it comes to the field of emergency response applications. In these systems, the critical part is the communication network which must be resilient to failures in order to realize reliable information distribution. Reliability must be implemented in software and hardware throughout all the IoT layers. In order to have an efficient IoT, the underlying communication must be reliable, because for example by an unreliable perception, data gathering, processing, and transmission can lead to long delays, loss of data, and eventually wrong decisions, which can lead to disastrous scenarios and can consequently make the IoT less dependable.

Reliability refers to the proper working of the system based on its specification.

Performance

Evaluating the performance of IoT services is a big challenge since it depends on the performance of many components as well as the performance of the underlying technologies. The IoT, like other systems, needs to continuously develop and improve its services to meet requirements of customers. The IoT devices need to be monitored and evaluated to provide the best possible performance at an affordable price for customers. Many metrics can be used to assess the performance of the IoT including the processing speed, communication speed, device form factor, and cost.

Performance evaluation of the individual underlying protocols and technologies, application layer protocols, and QoS have been reported in the literature, but the lack of a thorough performance evaluation for IoT applications is still an open issue.

Quality of service (QoS) is the overall performance of a telephony or computer network, particularly the performance seen by the users of the network.

Interoperability

End-to-end interoperability is another challenge for the IoT due to the need to handle a large number of heterogeneous things that belong to different platforms. Interoperability should be considered by both application developers and IoT device manufactures to ensure the delivery of services for all customers regardless of the specifications of the hardware platform that they use. For example, most of the smartphones nowadays support common communication technologies such as WiFi, NFC, and GSM to guarantee the interoperability in different scenarios. Also, programmers of the IoT should build their applications to allow for adding new functions without causing problems or losing functions while maintaining integration with different communication technologies. Consequently, interoperability is a significant criterion in designing and building IoT services to meet requirements of customers. Beside variety of protocols, different interpretations of the same standard implemented by different parties presents a challenge for interoperability. To avoid such ambiguities, interoperability testing between different products in a test-bed like ETSI Plugtests would be helpful. PROBE-IT is a research project that aims to ensure the interoperability of validated IoT solutions that conducted interoperability tests like CoAP, 6LoWPAN, and IoT semantic interoperability.

It is a known fact that two different devices might not be interoperable, even if they are following the same standard. This is a major showstopper for wide adoption of IoT technologies. Future tags must integrate different communication standards and protocols that operate at different frequencies and allow different architectur es, centralised or distributed, and be able to communicate with other networks unless global, well defined standards emerge.

Security and Privacy

Security presents a significant challenge for the IoT implementations due to the lack of common standard and architecture for the IoT security. In heterogeneous networks as in the case of the IoT, it is not easy to guarantee the security and privacy of users. The core functionality of the IoT is based on the exchange of information between billions or even trillions of Internet connection objects. One open problem in IoT security that has not been considered in the standards is the distribution of the keys amongst devices. On the other hand, privacy issues and profile access operations between IoT devices without interferences are extremely critical. Still, securing data exchanges is necessary to avoid losing or compromising privacy. The increased number of smart things around us with sensitive data necessitates a transparent and easy access control management in such a way that for example one vendor can just read the data while another is allowed to control the device. In this regard, some solutions have been proposed such as grouping embedded devices into virtual networks and only present desired devices within each virtual network. Another approach is to support access control in the application layer on a per-vendor basis.

Management

The connection of billions or trillions of smart devices presents service providers with daunting issues to manage the Fault, Configuration, Accounting, Performance and Security (FCAPS) aspects of these devices. This management effort necessitates the development of new light-weight management protocols to handle the potential management nightmare that will potentially stem from the deployment of the IoT in the coming years. Managing IoT devices and applications can be an effective factor for growing the IoT deployments. For example, monitoring the M2M communication of the IoT objects is important to ensure all times connectivity for providing on demand services. The Light-weight M2M (LWM2M) is a standard that is being developed by the Open Mobile Alliance to provide interface between M2M devices and M2M Servers to build an application agnostic scheme for the management of a variety of devices. It aims to provide M2M applications with remote management capabilities of machine-to-machine devices, services, and applications. The NETCONF Light protocol is an Internet Engineering Task Force (IETF) effort for the management of constrained devices provides mechanisms to install, manipulate, and delete the configuration of network devices. It is capable of managing a broad range of devices from resource-constrained to resource-rich devices. The independently developed MASH IoT Platform is an example of a platform that facilitates the management (monitoring, control, and configuration) of IoT assets anywhere in real-time using an IoT dashboard on smartphones. Maintaining compatibility across the IoT layers also needs to be managed to enhance connectivity speed and to ensure service delivery. The Open Mobile Alliance (OMA) Device Management working group is specifying protocols and mechanisms for the management of mobile devices and services in resource constrained environments.

Manufacturing

Manufacturing challenges must be convincingly solved. Costs must be lowered to less than one cent per passive RFID tag, and production must reach extremely high volumes, while the whole production process must have a very limited impact on the environment, be based on strategies for reuse and recycling considering the overall life-cycle of digital devices and other products that might be tagged or sensor-enabled.