Your LoRaWAN® Security Questions, Answered

To explore OTAA and ABP in depth, visit the Technology in Depth videos available on the LoRa Developer Portal.

Implementing a Secure LoRaWAN-based Application

The webinar then turns its focus to implementation. This involves following the LoRaWAN specifications and applying recommended practices to ensure backend security. Deployment is even more important, as this is where most common security flaws take place. The webinar concludes with the benefits of certifying one’s devices through the LoRa Alliance’s LoRaWAN Certified^CM program, as well as benefits of LoRa Alliance membership for those interested organizations and ecosystem businesses.

Webinar Q&A

Learn more about successfully deploying safe and secure LoRaWAN-based applications below, with a selection of the Q&A from the event.

What makes ABP particularly insecure?

With ABP, an end device keeps the same security session for its entire lifetime. It is recommended to use OTAA in end devices instead, as it can renew session, which is a security best practice. One should consider ABP for transmit-only devices.

What are some improvements LoRaWAN v1.0.4 and V1.1.1 will bring? Which version is recommended?

The current version of LoRaWAN link layer specification is 1.0.3. Version 1.0.4 will be published in the near future, and from a security standpoint, it mandates recommended best practices from v1.0.3. These include 32bit frame counters, never resetting frame counters for ABP devices and making DevNonce a counter. Once published, v1.0.4 will be the recommended version. The LoRa Alliance Technical Committee will then work on Version 1.1.1, which is a bigger implementation step, and will be interoperable and backwards compatible with all prior LoRaWAN specification versions (e.g., v1.0.3, v1.0.4) at both the end device and network levels. On the security side, Version 1.1.1. derives one session key per security usage, which is another good practice in security, and all MAC commands are encrypted. Version 1.1.1 also adds one root key, one for the network (NwkKey) and one for the application server (AppKey), to further separate the network from the application and add a mechanism for periodic session renewal. The main addition of 1.1.1 will be active roaming, so that the visited network can established a new security session with the roaming end device.

Why isn’t the Join Request encrypted?

The Join Request is addressed by the Join Server; it is received by a Network Server, then forwarded to be validated and actioned by the Join Server. If it was encrypted, since only one Join Server knows the root key for a given device, the Network Server would not be able to decrypt it, and therefore would not route the request.

What happens if a hacker uses a very high DevNonce, knowing the device will use its DevNonce as a counter?

The join request has a MIC which only the end device can compute, or the Join Server can verify, using the end device’s root key. It is not possible to spoof a join request frame or replay an old join request frame because the Join Server keeps track of the DevNonce, which increments at each new join request.

Do those deploying with Semtech’s new LoRa Edge™ LR1110 transceiver have to use a standard Join Server?

The LR1110 chip includes a hardware cryptographic engine dedicated to LoRaWAN security. It performs AES-128 computations, key derivation, MIC computation, Join Accept verification, and storage of secure root and session keys. Each chip comes with a EUI and a securely generated root key, which are also provisioned on Semtech’s Join Server. Of course, it is not mandatory to use this simplified provisioning, a manufacturer can provision a device on any other Join Server by utilizing a different EUI and root key during production.

To explore LoRaWAN security in depth and get a detailed explanation of how to implement applications resistant to today’s networking threats, watch the webinar on-demand now.

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