On Representing Resilience Requirements of Microservice Architecture Systems

TL;DR

This paper defines resilience for microservice architectures, proposes a measurement model, and introduces a requirements model to help developers specify and assess resilience in MSA systems.

Contribution

It provides a clear definition of microservice resilience, a measurement model, and a requirements model using KAOS, addressing the lack of consensus and guiding resilience specification.

Findings

Proposed a formal definition of microservice resilience.

Developed a measurement model for resilience assessment.

Validated models through a case study.

Abstract

Together with the spread of DevOps practices and container technologies, Microserivce Architecture has become a mainstream architecture style in recent years. Resilience is a key characteristic in Microservice Architecture Systems(MSA Systems), and it shows the ability to cope with various kinds of system disturbances which cause degradations of services. However, due to lack of consensus definition of resilience in the software field, although a lot of work has been done on resilience for MSA Systems, developers still don't have a clear idea on how resilient an MSA System should be, and what resilience mechanisms are needed. In this paper, by referring to existing systematic studies on resilience in other scientific areas, the definition of microservice resilience is provided and a Microservice Resilience Measurement Model is proposed to measure service resilience. And a requirement model to represent resilience requirements of MSA Systems is given. The requirement model uses elements in KAOS to represent notions in the measurement model, and decompose service resilience goals into system behaviors that can be executed by system components. As a proof of concept, a case study is conducted on an MSA System to illustrate how the proposed models are applied.