tenderitaf / anjay

C implementation of the client-side OMA LwM2M protocol

Anjay LwM2M library

What is Anjay?

Anjay is a C library that aims to be the reference implementation of the OMA Lightweight Machine-to-Machine (LwM2M) device management protocol. It eases development of fully-featured LwM2M client applications by taking care of protocol details, allowing the user to focus on device-specific aspects.

The project has been created and is actively maintained by AVSystem.

• Full documentation
• Tutorials
• API docs

Supported features

• LwM2M Bootstrap Interface:

  • Request
  • Finish
  • Write
  • Delete
  • Discover

• LwM2M Client Registration Interface:

  • Register
  • Update
  • De-register

• LwM2M Device Management and Service Enablement Interface:

  • Read
  • Discover
  • Write
  • Write-Attributes
  • Execute
  • Create
  • Delete

• LwM2M Information Reporting Interface:

  • Observe
  • Notify
  • Cancel Observation

• LwM2M Security modes:

  • DTLS with Certificates (if supported by backend TLS library)
  • DTLS with PSK (if supported by backend TLS library)
  • NoSec mode

• Supported TLS backends:

  • mbed TLS
  • OpenSSL

• CoAP data formats:

  • TLV
  • Opaque
  • Plain Text (including base64 encoding of opaque data)

• CoAP BLOCK transfers (for transferring data that does not fit in a single UDP packet):

  • Block1 (sending / receiving requests)
  • Block2 (sending responses)

• Pre-implemented LwM2M Objects:

  • Access Control
  • Security
  • Server

• Stream-oriented persistence API

About OMA LwM2M

OMA LwM2M is a remote device management and telemetry protocol designed to conserve network resources. It is especially suitable for constrained wireless devices, where network communication is a major factor affecting battery life. LwM2M features secure (DTLS-encrypted) methods of remote bootstrapping, configuration and notifications over UDP or SMS.

More details about OMA LwM2M: Brief introduction to LwM2M

Quickstart guide

"One"-liner for Ubuntu 16.04 LTS

To install all necessary packages, compile Anjay demo client and connect it to a local LwM2M server listening on default 5683 port:

sudo apt-get install git build-essential gcc cmake libmbedtls-dev \
    && git clone https://github.com/AVSystem/Anjay.git \
    && cd Anjay \
    && git submodule update --init \
    && cmake . \
    && make -j$(nproc) \
    && ./output/bin/demo --server-uri coap://127.0.0.1:5683

Dependencies

• C compiler with C99 support,
• CMake 2.8.8+,
• avs_commons - included in the repository as a subproject,
• If DTLS support is enabled, at least one of:
  • OpenSSL 1.1+,
  • mbed TLS 2.0+,
• Optional dependencies (required for tests):
  • C++ compiler with C++11 support,
  • Python 3.5+,
  • boost::python.

Compiling, installing, running

First, make sure all necessary submodules are downloaded and up-to-date:

git submodule update --init

To compile the library and demo application:

cmake . && make -j$(nproc)

Compiled executables, including demo client, can be found in output/bin subdirectory.

For a detailed guide on configuring and compiling the project (including cross-compiling), see Compiling client applications.

To start the demo client:

# uses plain CoAP
./output/bin/demo --server-uri coap://127.0.0.1:5683

# uses DTLS in PSK mode, with PSK identity "foo" and secret key "bar" (hex-encoded)
./output/bin/demo --server-uri coaps://127.0.0.1:5684 --security-mode psk --identity 666f6f --key 626172

NOTE: When establishing a DTLS connection, the URI MUST use "coaps://". In NoSec mode (default), the URI MUST use "coap://".

Running tests:

./devconfig && make check

License

See LICENSE file.

Commercial support

Anjay LwM2M library comes with the option of full commercial support, provided by AVSystem.

Contributing

Contributions are welcome! See our contributing guide.