Section Introduction

In this lesson we’ll cover two focused areas:

What a service mesh is and the core concepts behind it (traffic management, security, observability, and policy).
How Cilium implements service-mesh capabilities — the architecture, underlying technologies (notably eBPF), and the key features that make Cilium suited for modern microservices environments.

This lesson assumes familiarity with Kubernetes and basic networking concepts. If you’re new to Kubernetes, start with the Kubernetes Basics guide. For hands-on Cilium material, see the Cilium documentation.

What you’ll learn:

Topic	Why it matters	Outcome
Service mesh fundamentals	Understand the problems service meshes solve in microservice architectures	Be able to explain traffic control, mTLS, and observability concepts
Cilium architecture	Learn how Cilium uses eBPF and integrates with proxies	Understand Cilium’s design tradeoffs and how it enforces policies
Key features & components	Compare traffic management, security, and monitoring features	Know which Cilium components (e.g., Hubble, Envoy integration) are involved

Core concepts covered (brief):

Traffic management: routing, retries, circuit breaking, L7 vs L4 control.
Security: identity, mTLS, and authorization policies.
Observability: distributed tracing, flow visibility, metrics and logs.
Policy enforcement & performance: how kernel-level technologies improve policy performance.

Helpful references:

In the sections that follow we’ll expand each concept and map it to Cilium’s components and architecture, so you can see both the theoretical and implementation sides of a service mesh.

Watch Video

Policy Audit Mode

What is a Service Mesh

Introduction

Cilium Overview

Installing & Configuring Cilium

Exploring Cilium

Network Policy

Service Mesh

Cluster Mesh

Observability

BGP & External Networking

Optimization

Section Introduction

Watch Video