When we talk about Internet of Things (IoT), security is one of the issues that most worries users. The new IoT networks, such as NarrowBand IoT (NB-IoT) and LTE-M, have made it possible to access the Internet more economically and for a long time without maintenance due to low power consumption. However, there is a market concern about how to handle the security of the data these devices report. In this article, we’ll focus on the security in the communications of devices that use the NB-IoT network and communicate with a server in the cloud.

Understanding IoT Security

Before delving into the NB-IoT network, it is necessary to consider three basic pillars of IoT security that provide a comprehensive view of the topic:

• Authentication: This ensures that the device sending data to the cloud is authorized and has not been replaced. It also guarantees to the device that the cloud it is exchanging information with is genuine and not being substituted or having its data illicitly appropriated.
• Encryption: This ensures that a communications observer cannot understand the messages, and only the cloud with the decryption keys can retrieve them.
• Non-manipulation: This ensures that no one has altered the message that the IoT device sends to the cloud.

The NB-IoT Network and Its Security

Within a NB-IoT network, data travels encrypted, ensuring security. The problem arises once the data leaves the NB-IoT network and is sent over the Internet, from the network operator’s servers to the final cloud server where the client has installed its reception center and data processing.

Typically, NB-IoT uses the UDP protocol. It is a very simple protocol and ideal for NB-IoT due to its low consumption, as it does not require establishing a connection to send data. When a flat UDP packet travels over the Internet, all of its data is visible to third parties.

Ensuring Security with Low Power Consumption

If we want to utilize one of the main features of NB-IoT: achieving the lowest possible consumption among all LPWAN networks, we must use the UDP protocol, which is inherently unsafe. But can we still maintain low power consumption using UDP and ensure security in communications? The answer is yes.

Methods for Managing Safety in NB-IoT

There are different methods for managing security in an NB-IoT communications network, between devices and the cloud server where information is reported.

• APN or Operator Platform: Some operators offer the possibility of setting up an intermediate server that collects data from the NB-IoT network without going through the Internet. The customer’s final platform is typically connected via a secure VPN connection to the operator’s platform, making the entire path from the device to the customer’s cloud server secure.

In favor: High security level | Rapid solution development.
Against: It implies costs for the customer | Little flexibility to operator changes.

• UDP Protocol Securing: In this case, data travels end-to-end encrypted by the same technology, and the cloud server is responsible for authenticating and decoding the data.

In favor: High security level | Independent of the network operator.
Against: Solution development time.

• Do Not Apply Security: This is the easiest possibility but is not recommended. This option could be considered only in performance tests, as real and volume projects could receive multiple attacks without any ability to cope.

In favor: Simplicity | Easy to develop.
Against: The data is compromised | Susceptible to attacks of all kinds.

As NB-IoT device developers, we are fully aware of the importance of applying security to devices. Therefore, not applying security is not an option in our projects.

Need more information on security and IoT devices? Our CTO, Oriol Patau, gives us the keys to understand how IoT devices can be secured: