How a Service Mesh Works

What is a service mesh? It is a method of controlling how various sections of an application communicate data. A service mesh, as opposed to other solutions for handling this communication, is a specialized infrastructure layer embedded directly within an app. This transparent service mesh architecture can document how smoothly (or poorly) various portions of an app connect, making it easier to enhance communication and reduce downtime as the app expands.

Each component of an app, known as a "service," relies on other services to provide consumers with what they require. If a buyer of an online retail app wishes to buy something, they must first determine if the thing is in stock. As a result, the service that connects with the company's inventory database must also communicate with the product homepage, which then communicates with the user's online shopping cart. This shop may someday develop a service that provides customers with in-app product suggestions to enhance commercial value. This new service will generate suggestions by communicating with a database of product tags, but it will also need to interact with the same inventory database of the product page required.

Modern applications are frequently divided into networks of services, each executing a distinct business function. One service may need to request data from numerous other services in order to perform its role. What happens if some services get overwhelmed with requests? This is where a service mesh comes into play—it sends requests from a service to the next while optimizing how all the moving pieces interact.

Isn't this Something that Microservices Do?

A microservices design enables developers to change an app's services without the need to reinstall it. Individual microservices, unlike app development in other designs, are produced by small teams with the freedom to use their own tools and coding languages. Microservices are designed independently, communicate with one another, and can fail without causing an application-wide outage.

Microservices are made workable via service-to-service communication. Without a service mesh layer, the logic regulating communication may be built into each service; but, as communication becomes more sophisticated, a service mesh becomes increasingly beneficial. A service mesh provides a means to combine numerous discrete services into a working application for cloud-native apps created in a microservices architecture.

How Service Mesh Works

A service mesh does not provide new capabilities to an app's runtime environment. Programs in whatever architecture have always required rules to indicate how requests are routed from point A to point B. A service mesh differs in that it abstracts the logic regulating service-to-service communication away from individual services and onto infrastructure layers.

A service mesh is integrated into an app as an array of network proxies to accomplish this. Proxies are common in workplace IT. If you're reading this on a work computer, you've probably already used one.

Your company's web proxy originally received your request for this page.
It was sent to the server that hosts this page after passing the proxy's security check.
This page was then returned to the proxy and examined again against its security measures, then delivered to you from the proxy.

Requests are routed across microservices in a service mesh using proxies on their respective infrastructure layer. As a result, the various proxies that comprise a service mesh are frequently referred to as "sidecars," because they operate alongside rather than within the services. These "sidecar" proxies, which are divorced from each service, form a mesh network when combined.

Without a service mesh, each microservice must be programmed with logic to control service-to-service communication, requiring developers to focus less on business goals. It also makes it more difficult to detect communication issues since the logic that regulates inter-service communication is contained within each service.