  On the Internet of Things (IoT), devices continuously communicate with each
other, with a gateway, or other Internet nodes. Often devices are constrained
and use insecure channels for their communication, which exposes them to a
selection of attacks that may extract sensitive pieces of information or
manipulate dialogues for the purpose of sabotaging.
  This paper presents a new layer in the RIOT networking architecture to
seamlessly integrate secure communication between applications using DTLS. The
layer acts as a modular abstraction layer of the different DTLS
implementations, enabling swapping of the underlying implementation with just a
few lines of code. This paper also introduces credman, a new module to manage
credentials used for (D)TLS connections.
