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.

Supported features
About OMA LwM2M
Quickstart guide
License
- Commercial support
Contributing

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
- tinydtls
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

Dependencies

C compiler with C99 support,
CMake 2.8.11+,
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+,
- tinydtls 0.9+,
Optional dependencies (required for tests):
- C++ compiler with C++11 support,
- Python 3.5+,
- boost::python.

To install everything on Ubuntu 16.04 LTS:

sudo apt-get install git build-essential cmake libmbedtls-dev wget
# Optionally for tests:
sudo apt-get install libboost-python-dev libpython3-dev libssl-dev python3

Or on macOS Sierra with Homebrew:

brew install cmake mbedtls wget
# Optionally for tests:
brew install python3 && brew install boost-python --with-python3

Running the demo client

To compile Anjay demo client and connect it to a local LwM2M server listening on default 5683 port:

git clone https://github.com/AVSystem/Anjay.git \
    && cd Anjay \
    && git submodule update --init \
    && cmake . \
    && make -j \
    && ./output/bin/demo --server-uri coap://127.0.0.1:5683

Detailed compilation guide

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

git submodule update --init

By default demo client compiles with DTLS enabled and uses mbedtls as a DTLS provider, but you may choose other DTLS backends currently supported by setting DTLS_BACKEND in a CMake invocation to one of the following DTLS backends: openssl, mbedtls or tinydtls:

cmake . -DDTLS_BACKEND="mbedtls" && make -j

Or, if a lack of security (not recommended) is what you need for some reason:

cmake . -DDTLS_BACKEND="" && make -j

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.

JackieXie168/Anjay