# Zest: REST over ZeroMQ

## TL;DR

Zest is a middleware that combines RESTful architecture with ZeroMQ to enable fine-grained access control, asynchronous communication, and enhanced routing for IoT systems, especially in contexts requiring strict communication policies.

## Contribution

It introduces Zest, a novel middleware that integrates REST over ZeroMQ with advanced access control and routing, tailored for IoT and data privacy applications.

## Key findings

- Supports fine-grained access control for resources and audit info
- Enables asynchronous communication patterns between nodes
- Provides enhanced routing support in a hybrid REST and publisher/subscriber topology

## Abstract

In this paper, we introduce Zest (REST over ZeroMQ), a middleware technology in support of an Internet of Things (IoT). Our work is influenced by the Constrained Application Protocol (CoAP) but emphasises systems that can support fine-grained access control to both resources and audit information, and can provide features such as asynchronous communication patterns between nodes. We achieve this by using a hybrid approach that combines a RESTful architecture with a variant of a publisher/subscriber topology that has enhanced routing support. The primary motivation for Zest is to provide inter-component communications in the Databox, but it is applicable in other contexts where tight control needs to be maintained over permitted communication patterns.