Towards Seamless IoT Device-Edge-Cloud Continuum:

Abstract

In this paper we revisit a taxonomy of client-side IoT software architectures that we presented a few years ago. We note that the emergence of inexpensive AI/ML hardware and new communication technologies are broadening the architectural options for IoT devices even further. These options can have a significant impact on the overall end-to-end architecture and topology of IoT systems, e.g., in determining how much computation can be performed on the edge of the network. We study the implications of the IoT device architecture choices in light of the new observations, as well as make some new predictions about future directions. Additionally, we make a case for isomorphic IoT systems in which development complexity is alleviated with consistent use of technologies across the entire stack, providing a seamless continuum from edge devices all the way to the cloud.

Towards Characterization of Edge-Cloud Continuum

“…Software platforms running on that hardware are also very heterogeneous. In general, they can be categorized into [36]: device-specific firmware without an OS, real-time OS, language runtime, full OS (e.g. Linux), App OS (e.g.…”

“…Yet, edge-cloud continuum, as it is envisioned, should be able to run the same software components on different levels of the continuum, depending on the current needs of individual applications and overall circumstances [36][23][34]. This means that the ECC environment has to be able to support fully liquid software [36].…”

“…The term liquid software refers to the kind of software that can move between multiple devices in a seamless manner [14]. In the context of ECC, this can mean two things: either seamless migration and handover of software components between the nodes of the same type (which has been already demonstrated [12]), or seamless migration between devices of different types (which is currently only an idea [36]). We will refer to software that can perform both kinds of migrations as fully liquid software.…”

“…And while we probably can expect some further incremental quantitative improvements in hardware capabilities, it is not guaranteed that they will be sufficient to provide a platform for the implementation of some envisioned features of ECC. For instance, achieving fully isomorphic software [36] would require end devices to be able to host containerized applications, at least in some form. Whether this is possible in principle, especially for devices running real-time operating systems, is not yet clear.…”

“…In this search for a unifying paradigm, there has been proposed the concept of Edge-Cloud continuum (ECC) [23] (also referred to as Mobile-Edge-Cloud Continuum [4] and Device-Edge-Cloud Continuum [36]). This concept envisions the cloud-to-end-device chain as a single unified space with flexible boundaries between levels, in which applications coexist in a highly distributed, yet highly interconnected and resource-rich environment.…”