Transparent Web of Things Discovery in Constrained Networks based on mDNS/DNS-SD

Over the past few years, IoT (Internet of Things) technologies have become pervasive. Many IoT systems and applications have been proposed and deployed. As IoT devices are with restricted computation, storage, and power, these devices are usually connected by LLN (Low-power and Lossy Network), where the devices are only accessible via a gateway. As a result, it is tedious to integrate existing IP-based applications with the IoT devices as existing well-developed management protocols do not fit well to the devices within the LLN. This paper proposes a framework and a set of schemes that facilitate transparent discovery and access from an IP network to the devices in the LLN. With the proposed schemes, a client is able to discover IoT devices in a 6LoWPAN-based LLN using mDNS/DNS-SD service discovery protocol. The proposed design has been realized as add-on modules of an LLN gateway. Validations and experiments are also performed to verify the effectiveness of the proposed schemes.