Cross-Service Authentication Mechanisms in Applications with Microservice Architecture

Abstract

In this article discussed cross-service authentication. It is one of the most important aspects of security in modern applications with microservice architecture. The basic mechanisms of service-to-service authentication, such as tokens and certificates usage, are represented in the article. An example of service-to-service authentication architecture is also given. The article is a useful resource for developers who are working in the field of service-oriented architecture and interesting in security issues. It provides an extensive overview of authentication mechanisms and key points to consider during designing a microservice architecture. The article proposes to use the mutual TLS (mTLS) protocol, which is the most popular way to secure cross-service communication during microservices deploying. In this approach the responsible for the cross-service authentication lies with the mTLS proxy deployed for each microservice of the system. mTLS proxies work as intermediaries between the microservices, accepting requests for a secure communication channel establishment. The proxy approach simplifies the authentication process between two microservices, that can run on different platforms, by using different protocols and data formats. By using the mTLS proxy, the solution is easy to scale, because it is enough to deploy a new instance of the mTLS proxy in case of new microservices appearing in the system. Also, the proxy does not depend on the language or system implementing an associated microservice, which makes the solution universal.