A Deep Dive Into LoRaWAN Technology

LoRaWAN is a LoRa Alliance-developed Long Range Wide Area networking protocol that wirelessly connects "things" to the internet in regional, national, or global networks. This technology addresses key Internet of Things (IoT) requirements such as bi-directional communication, end-to-end security, mobility, and localization services. It defines the network's communication protocol and system architecture using unlicensed spectrum in the ISM bands, while the LoRa physical layer establishes long-range communication links between remote sensors, beacons, and gateways connected to the network. This protocol aids in the rapid establishment of public or private IoT networks utilizing hardware and software from any location. With LoRaWAN, an end device may connect to a network in two ways:

1. Over-the-Air Activation (OTAA): To connect to the network, a device must first establish a network key and an application session key.
2. Activation by Personalization (ABP): A device's keys for communicating with the network are hardcoded, resulting in a less secure but simpler connection.

How Secure Is LoRaWAN?

LoRaWAN has one security layer for the network and one for the application. The application layer of security guarantees that the network operator does not have access to the end user's application data, while network security assures that each node in the network is legitimate. As a result, the LoRaWAN standard provides two cryptographic layers:

1. The end device and the network server exchange a 128-bit Network Session Key.
2. At the application level, a unique 128-bit Application Session Key (AppSKey) is shared end-to-end.

Data is encrypted by the node and then encrypted again by the LoRaWAN protocol before being transferred to the LoRa Gateway. The Gateway transmits data to the network server via a standard IP network. The network server decrypts the LoRaWAN data using the Network Session Keys (NwkSkey). It then sends the data to the application server, which uses the Application Session Key to decrypt the data (AppSKey).

The encryption will then be added to the LoRaWAN communication protocol. However, LoRa transmissions are basic radio wave communications that cannot be encrypted on their own. If a LoRaWAN device to connects to the network through Over-the-Air-Activation or OTAA, a128-bit AppKey is exchanged between the device and the network. The AppKey is used to construct a Message Integrity Code (MIC) when the device sends the join request, and the server then compares the MIC to the AppKey.

If the check is successful, the server generates two new 128-bit keys: App Session Key (AppSkey) and Network Session Key (NetSkey) (NwkSkey). The AppKey is used as an encryption key to send these keys back to the device. The device decrypts and installs the two session keys after the keys are received. 

Advantages of LoRaWAN Technology

There are many advantages to LoRaWAN technology. Let's take a look:

• It has a large coverage area measured in kilometers.
• Operate on free frequencies with no upfront licensing fees.
• Gadgets have a long battery life, and device batteries can last for 2–5 years.
• A non-proprietary partnership with an open approach.
• The extended range allows smart city applications, but the low bandwidth makes it excellent for realistic IoT installations with limited data and/or variable data transfers.
• Cheaper connectivity costs, is wireless, and is simple to set up and deploy.
• With AES encryption, completely bi-directional communication, and the backing of CISCO, IBM, and 500 other LoRa Alliance member firms, it has a layer of security for the network and one for the application.

Apart from industry-specific implementations, LoRaWAN enables IoT in emerging nations where high-cost 5G alternatives are too expensive. The technology greatly decreases the cost of deployment due to its flexible, relatively simple design and minimal network hardware requirements, while its low energy consumption generates further savings in running expenditures. LoRaWAN, which was created to link devices to the internet wirelessly, is ideal for IoT sensors, trackers, and beacons with modest data traffic requirements and limited battery life. The protocol's inherent properties make it an excellent candidate for a wide range of applications.

Limitations of LoRaWAN Technology

Though there are many great advantages listed above for this technology, there are still many limitations. Let's look at some possibilities:

• Large data payloads, continuous monitoring, and hard real-time applications needing reduced latency (typically in milliseconds) and defined jitter are not compatible with this technology.
• As the deployment of gateways populates metropolitan areas, the growth of LPWAN technologies, notably LoRaWAN, offers coexistence issues. Open frequency has the disadvantage of being susceptible to interference and having a poor data rate.

The Justified Interest In LoRaWAN

LoRaWAN Technology is a new buzzword in the IoT field. As IoT continues to expand and become more popular, it's important we understand the security, advantages, and disadvantages of any new technology. LoRaWAN's ability to enable IoT where high-cost 5G is too expensive, along with its ability to decrease the overall cost of deployment, certainly makes it a superior technology. However, its other advantages and limitations must be weighed carefully for your specific use case.