Dynamic Distributed Orchestration of Node-RED IoT Workflows Using a Vector Symbolic Architecture

Abstract

There are a large number of workflow systems designed to work in various scientific domains, including support for the Internet of Things (IoT). One such workflow system is Node-RED, which is designed to bring workflow-based programming to IoT. However, the majority of scientific workflow systems, and specifically systems like Node-RED, are designed to operate in a fixed networked environment, which rely on a central point of coordination in order to manage the workflow. The main focus of the work described in this paper is to investigate means whereby we can migrate Node-RED workflows into a decentralized execution environment, so that such workflows can run on Edge networks, where nodes are extremely transient in nature. In this work, we demonstrate the feasibility of such an approach by showing how we can migrate a Node-RED based traffic congestion workflow into a decentralized environment. The traffic congestion algorithm is implemented as a set of Web services within Node-RED and we have architected and implemented a system that proxies the centralized Node-RED services using cognitively-aware wrapper services, designed to operate in a decentralized environment. Our cognitive services use a Vector Symbolic Architecture to semantically represent service descriptions and workflows in a way that can be unraveled on the fly without any central point of control. The VSA-based system is capable of parsing Node-RED workflows and migrating them to a decentralized environment for execution; providing a way to use Node-RED as a front-end graphical composition tool for decentralized workflows.

Pragmatic Interoperability for Extreme Automation and Healthcare Interoperability and Continuity

“…However, languages for describing workflows tend to be highly complex, or specialized towards a particular domain, or both. However, Node-Red provided more general and flexible workflow programming paradigm which is originally designed for extreme automation [18]. This paper presents ExtremeFlow: an approach to workflow programming which combines the advantages of a declarative workflow description and web services programming.…”

Pragmatic Interoperability for Extreme Automation and Healthcare Interoperability & Continuity

“…One such workflow system is Node-RED , which is originally designed to bring workflow-based programming to IoT and extreme automation. However, the majority of workflow systems including Node-RED, are designed to operate in a fixed networked environment, which rely on a central point of coordination in order to manage the workflow [18]. This paper presents ExtremeFlow: an approach to workflow programming which combines the advantages of a declarative workflow description and web services programming.…”

Enabling Discoverable Trusted Services for Highly Dynamic Decentralized Workflows

“…As such, a mechanism is needed that can locate and orchestrate the required workflow in the face of these challenges, without central control since it in not possible to rely on centralised registries, or even to know the IP location of objects and devices as they come in and out of service. As described in [1], [2], [3], the VSA architecture can be used for peer-to-peer (P2P) discovery of appropriate devices and functional micro-services without service and device registries because the VSA representation is able to act as both the object description and the address of the object.…”

“…Our approach for creating semantically rich representation of services and workflows is to represent them as high level semantic concept vectors that are themselves constructed from semantic vectors representing their sub features in a recursive manner using vector binding and superposition operations as described in [3], [2]. Reviewing that X r represents a role vector and Y v a value vector, role vectors can be bound to filler vectors using the binding operation X r .…”

“…As a result, dynamic workflow configuration needs to be able to provide rapid and autonomous discovery and configuration of suitable resources from a plethora of available devices and services, based on factors such as capabilities and quality of service, and augmented by networks of trust. The author's previous work has shown that decentralized workflow mechanisms, such as those based on Vector Symbolic Architectures (VSA), can be used to facilitate efficient service discovery and workflow formulation in decentralized collaborative environments [1], [2], [3], without requiring central control [4]. Such decentralized mechanisms are well suited to the low latency, high capacity, and high bandwidth connectivity afforded to edge computing resources as part of 5G networks, and the business and research ecosystems that they will support.…”