architecture.md

title	layout	prism_languages	weight	tags	updated	category	intro
Architecture	2017/sheet	bash yaml	-3	Featured	2022-08-04	Concepts	Istio concepts.

Intro

Architecture

Istio Architecture

Istio control plane is a single process - istiod, which contains three components Pilot, Citadel and Galley. You can bring containers in Kubernetes and virtual machines into the Istio mesh together.

{:data-img="img/istio-arch.svg"}

Components

The following figure show the components in Istio mesh.

{:data-img="img/istio-components.svg"}

Transparent Traffic Hijacking

The following figure shows the transparent traffic hijacking and traffic routing in Istio.

{:data-img="img/transparent-traffic-hijacking.svg"}

Note

• Only TCP traffic is shown in the figure. Traffic for UDP and other protocols will not be hijacked.
• It is based on Istio 1.14.
• It shows the traffic routing in reviews pod of the Bookinfo sample.

Data Plane

Envoy is the default sidecar proxy in Istio.

{:data-img="img/envoy-arch.svg"}

See Envoy section.

Envoy

xDS

Istiod distributes the proxy configurations to Envoy via xDS protocol.

{:data-img="img/xds.svg"}