What is a service mesh?

A service mesh is best understood as a dedicated infrastructure layer that manages service-to-service communication over a network. It provides critical functionalities such as service discovery, load balancing, failure recovery, metrics, and monitoring, as well as often implementing security features like authentication and authorization.

In a microservices architecture, where there are numerous independent services that communicate with each other, managing these communications can become complex. The service mesh simplifies this process by providing a standardized way to manage network traffic between those services. This helps ensure that they can communicate reliably and securely, regardless of how many services are involved or how they are deployed.

Other options describe concepts that do not align with the functionality of a service mesh. For example, a programming language for microservices would be a tool to write microservice code, not to manage communication between services. A database management system relates specifically to data storage and retrieval rather than communication structure. Lastly, a user interface for managing microservices focuses on the interface aspect to operate microservices rather than the underlying communication mechanisms that a service mesh addresses.