Tobias Buchberger

Researcher, Competence Centre for IT-Security, FH Campus Wien, "CoMatrix - How to overcome kernel panic, deal with buffer limitations and LOL at random"


CoMatrix – How to overcome kernel panic, deal with buffer limitations and LOL at random


Tobias Buchberger is a researcher at the Competence Centre for IT-Security at FH Campus Wien, where he also pursued his IT security studies. Before joining FH Campus Wien, he was working as an IT security analyst at a Viennese-based company for several years.


We will present our prototype implementation of the CoMatrix project, which enables the usage of the Matrix protocol for constrained IoT devices via CoAP and CBOR in a constrained network (e.g. a 802.15.4/6LoWPAN network). A CoMatrix gateway, which acts as a CoAP-HTTP forward proxy, was implemented based on the Python library aiocoap, and is running on a Raspberry Pi, which was extended with a 802.15.4 radio module. On the client side we use RIOT-OS on a SAMR21-xpro board and implemented an external CoMatrix library module based on gcoap and nanocoap. We like to share our experiences during the implementation and discuss some problems we faced, e.g.: Everything but Random – randomization of gcoap token on reset; Still not able to talk in secret – DTLS, OSCORE or openthread? Furthermore, we will give a short demo of two IoT use case applications: First the “CoMatrix chat” to show our current state of the client library functions. The latter is a temperature sensor application, which continuously sends temperature values into a Matrix room.

Photo: Copyright © FH Campus Wien/Schedl