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In order to extend the Internet technologies into constrained networks, there have been several research efforts and innovations over the past few years. These efforts resulted in several networking standards and protocols which have led to the emergence of the Internet of Things (IoT). Within this enormous ecosystem of protocols, the Lightweight Machine-to-Machine (LwM2M), a standard for device and service management, is a very promising candidate to achieve global interoperability, especially when constrained devices are involved. In this paper, we propose extensions to the LwM2M in order to improve communication efficiency and introduce Intermittent Connectivity, which will improve support for Low-Power Wide Area Networks (LPWANs) in LwM2M. For this purpose, we introduce two new object models, namely, Notify and Batch. The Notify Object enables the creation of reverse interaction models and Ready-to-Receive (RTR) functionality, which allows LwM2M clients to send periodic updates of resources without any need for a request and to notify LwM2M servers that it is ready to receive downlink messages and to keep the network connectivity open if it is necessary for downlink communication. Finally, the Batch object allows LwM2M servers to perform actions on multiple resources in a device via a single request.

Smart embedded objects will become an important part of what is called the Internet of Things. However, the integration of embedded devices into the Internet introduces several challenges, since many of the existing Internet technologies and protocols were not designed for this class of devices. In the past few years, there were many efforts to enable the extension of Internet technologies to constrained devices. Initially, this resulted in proprietary protocols and architectures. Later, the integration of constrained devices into the Internet was embraced by IETF, moving towards standardized IP-based protocols. Long time, most efforts were focusing on the networking layer. More recently, the IETF CoRE working group started working on an embedded counterpart of HTTP, allowing the integration of constrained devices into existing service networks. In this paper, we will briefly review the history of integrating constrained devices into the Internet, with a prime focus on the IETF standardization work in the ROLL and CoRE working groups. This is further complemented with some research results that illustrate how these novel technologies can be extended or used to tackle other problems.