Here is a glossary of common Istio words and phrases.
Destination. The remote upstream service Envoy is talking to on behalf of a Source Workload. There can be one or more Service Versions for a given Service and Envoy chooses the version based on routing rules.
Envoy. The high-performance proxy that Istio uses to mediate inbound and outbound traffic for all Services in the Service Mesh. Learn more about Envoy.
Istio mutual TLS Authentication. Provides strong service-to-service authentication using mutual TLS, with built-in identity and credential management. Learn more about Istio mutual TLS authentication.
Mixer. The Istio component responsible for enforcing access control and usage policies across the Service Mesh and collecting telemetry data from Envoy and other services. Learn more about Mixer.
Pilot. The Istio component that programs the Envoy proxies, responsible for service discovery, load balancing, and routing.
Secure Naming. Provides a mapping between a Service Name and the Workload Principals that are authorized to run the Workloads implementing a Service.
Service. A delineated group of related behaviors within a Service Mesh. Services are named using a Service Name, and Istio policies such as load balancing and routing are applied using Service Names. A Service is typically materialized by one or more Service Endpoints, and may consistent of multiple Service Versions.
Service Consumer. The agent that is using a Service.
Service Endpoint. The network-reachable manifestation of a Service. Service Endpoints are exposed by Workloads. Not all Services have Service Endpoints.
Service Mesh. A shared set of names and identities that allows for common policy enforcement and telemetry collection. Service Names and Workload Principals are unique within a Service Mesh.
Service Operator. The agent that manages a Service by manipulating configuration state and monitoring Service health via a variety of dashboards.
Service Producer. The agent that creates a Service and manages which Service Consumers may use it.
Service Version. Distinct variants of a Service, typically backed by a different version of a Workload binary. Common scenarios where multiple Service Versions may be used include A/B testing, canary rollouts, etc. Each Service has a default Service Version.
Source. The downstream client of Envoy. Within the Service Mesh a Source is typically a Workload, but the Source for ingress traffic may include other clients such as a browser or mobile app.