This is an implementation of the DLMS/Cosem protocol using the MIT Open Source and permissive license. This protocol is mainly used in gas/water/electricity meters but is enough generic to target any IoT device.

See the official organization group to learn more: http://www.dlms.com.

The protocol stack is developped in C/C++ languages, the code stack is in C, the client is in C++.

This Cosem stack has the following goals :

• Pure portable and stand-alone ANSI C99 code
• Fully unit tested with pre-defined vectors
• Client/server implementation, LogicalName referencing, LLS, HLS3, 4 and 5, security policy 1
• Examples using Cosem over TCP/IP
• Memory efficient / no dynamic allocation (static, configurable at build-time) / limited buffer copy
• Full traces
• Memory protected against buffer overflow using array utility

• BER coder/decoder
• Association coders and decoders AARQ/AARE/RLRQ/RLRE (LLS)
• Secure HLS5 GMAC Authentication
• Get Request normal and by block (object list example)
• Action service
• Exception response in case of problem
• HDLC framing utility
• Serial port HAL (Win32/Linux)
• Utilities
• Client reader over HDLC with full logging and XML output
• Server example as a meter simulator using TCP/IP Wrapper

### Public client, no security:

• Set request by block
• Client is currently broken due to shared source code changes
• Scripting GUI tool prototype to repair (need the client to be repaired first)

• cosemlib: kernel files of the DLMS/Cosem protocol
• client: specific utilities to write a DLMS/Cosem client
• server: specific utilities to write a DLMS/Cosem server
• examples: Client/server examples
• studio: Graphical utility with Lua scripting (WIP)
• tests: Unit tests for the protocol with raw frames and application objects

You must have CMake and a C/C++ compiler. Examples generate stand alone executables, other repositories generate static libraries.

The top level cmake file will build everything:

mkdir build
cd build
cmake ..
make

cd examples/metersimulator
mkdir build
cd build
cmake ..
make

The best way is to use VSCode, there are pre-configured settings in the .vscode directory to build, execute demos and debug.

FIXME: before writing this section, wait for stabilization of the HAL/Cosem API and utilities

• LN with ciphering Security Policy 0 (Authenticated & encrypted)
• HLS 3, 4, 5, 6
• Get with multiple references
• Selective access by date and range

• Multiple logical devices support
• ACCESS service
• GBT service
• ECDSA
• ECDSA data transport cyphering