Inside Out | Semtechの企業ブログ

BLG | AMW | WRF - IPv6 Officially Enters the LoRaWAN® Ecosystem

Written by Alper Yegin | 06 August 2024

Support for IPv6 over LoRaWAN® is officially qualified by the LoRa Alliance® in the LoRaWAN® IPv6 Adaptation Layer for End-Devices Specification TS010 technical specification.

SCHC Adaptation Layer

This new functionality leverages the SCHC adaptation layer, as defined by the Internet Engineering Task Force (RFC 8724, 9011) – the IETF is the international body defining the standards that guarantee the interoperability and the evolution of the Internet. SCHC, pronounced “chic”, is a compression and fragmentation mechanism that avoids the bandwidth-intensive operation of synchronization among network entities. It relies on a simple principle: given the highly-predictable nature of IoT data flows, communication contexts can be written, shared and stored in advance. This can drastically reduce the amount of data transmitted over networks, thus enabling the support of IPv6 and related upper application layer communications.

LoRaWAN Network Specifics Handled by SCHC

Challenge #1:

The use of IPv6/UDP adds at least 48 bytes of header to the payload, which makes its use on LoRaWAN networks inefficient, if not impossible.

  • SCHC compression reduces the IPv6/UDP header so that it is carried as a RuleID of one byte within the LoRaWAN frame.

Challenge #2:

IPv6 Maximum Transmission Unit (MTU) requires that the access network handle packets of at least 1280 bytes, way beyond the 256-byte maximum capabilities of LoRaWAN.

  • SCHC includes optional fragmentation and reassembly for transmitting larger packet sizes than the LoRaWAN payload size. It is especially designed to save downlinks.

Challenge #3:

IPv6 requires a permanent, bidirectional dialogue to maintain connection between network elements.

  • SCHC architecture prevents continuous synchronization, thus saving bandwidth while maintaining communication contexts.

Challenge #4:

Variability of LoRaWAN parameters among regions, operators and radio conditions (behavior, data rates, message sizes, etc.)

  • The SCHC implementation dynamically adapts fragmentation to the underlying network conditions and capabilities.

Set Up Overview

The end device sends legacy application messages, transported in IPv6 packets, over the LoRaWAN link. To do so, the packets are fragmented and compressed by Actility's SCHC implementation. A context is shared between the end device and the Core network.

Figure 1: SCHC adaptation layer architecture for IPv6 over LoRaWAN, Image courtesy of Actility

To enable IPv6 over LoRaWAN, the implementation requires:

  • A library embedded in the device (on either CPU, communication module or SoC): Actility SCHC library
  • And a SCHC gateway between the LoRaWAN network server and the service application: Actility IP Core

Figure 2: Actility SCHC software suite, Image courtesy of Actility

Bringing Seamless Interoperability with IPv6 Support

The Internet protocol (IP) acts as a pivot between application-layer and lower-level network protocols, hiding the differences among access technologies. It also presents a unified service interface to applications. This way, applications can route messages without worrying about the underlying network technology.

SCHC transforms a LoRaWAN end device into an IPv6 object that is statically provisioned and easily addressable from any Internet application. It maintains the client's IP-based application environment, end-to-end, from the device to the application. SCHC enables seamless integration of devices connected to a LoRaWAN network with the rest of the customer's network and application solutions.

SCHC makes LoRaWAN eligible for many use cases without impacting its performance in terms of energy efficiency or density of objects hosted on the network. Previously, LoRaWAN could be used on the edge of IP deployments with subsystems of sensors, connected to the IP world through protocol translation gateways. Now, customers can seamlessly add LoRaWAN to a portfolio of various connectivities to complement, densify, or even replace legacy connectivity from the IP world.

IPv6 Over LoRaWAN to Address New Markets

With SCHC, LoRaWAN will be able to fuel the demand for additional use cases and expansion into new markets. Not to mention the IoT ecosystems that are currently converging around IPv6 - such as Matter, previously known as Project Connected Home over IP (CHIP).

The first market targeted by this new IPv6 over LoRaWAN feature is, thanks to the support of the DLMS protocol, the deployment of multi-metering over LoRaWAN, enabling interoperability and common use of the same network and data platform, to connect all meter types. Now, with the available standard profile of DLMS over SCHC, on top of LoRaWAN for electricity meters and soon for water and gas meters, it’s possible to leverage a reliable standard ensuring simple and reliable integration. In addition, there is also the benefit of good mutualization; the network and data platform are now interoperable with a wider array of vendors.

Figure 3: DLMS/COSEM messages compressed by Actility SCHC for transmission over LoRaWAN - representing a compression ratio of 90% on the headers, and 75% when SCHC is applied to the whole IPv6/UDP/DLMS packet. Image courtesy of Actility

SCHC can be used to support IP-based applications and standards required in many verticals. From smart homes to smart logistics, to smart cities, countless use cases can now be envisioned. Actility's SCHC implementation allows, for example, densification of Modbus-based industrial automation networks over LoRaWAN, and using LoRaWAN as backup connectivity for classical IP routers.

Get Hands-on With the SCHC Developer Program

Following the specification of this new feature by the LoRa Alliance, Actility a pioneer and leader of the SCHC technology, makes this technology available to the widest possible audience with the opening of a developer program dedicated to LoRaWAN developers. Actility offers, for the first time, exclusive access to:

  • The Actility Cloud platform (community version)
  • The full documentation, with turnkey integration examples to facilitate your onboarding
  • A GitLab repository with access to the Actility SCHC library, as well as open-source application examples, including a reference implementation of LoRa Basics

Additional Resources

Semtech, the Semtech logo and LoRa are registered trademarks or service marks. LoRa Basics is a trademark or service mark of Semtech Corporation or its affiliates.