Choosing the Right OpenShift Service: Service Mesh, Submariner, or Service Interconnect?

In today’s digital world, businesses rely more and more on interconnected applications and services to operate effectively. This means integrating software and data across different environments is essential. However, achieving smooth connectivity can be tough because different application designs and the mix of on-premises and cloud systems often lead to inconsistencies. These issues require careful management to ensure everything runs well, risks are managed effectively, teams have the right skills, and security measures are strong.

This article looks at three Red Hat technologies—Red Hat OpenShift Service Mesh and Red Hat Service Interconnect, as well as Submariner—in simple terms. It aims to help you decide which solution is best for your needs.

OPENSHIFT
Feature	Service Mesh (Istio)	Service Interconnect	Submariner
Purpose	Manages service-to-service communication within a single cluster.	Enables communication between services in different OpenShift clusters on the same hardware.	Connects services across different networks/clusters (e.g., on-premises to cloud).
Key Benefits	Traffic management, security, observability.	Seamless cross-cluster communication on the same infrastructure.	Secure communication over the internet.
Use Case Example	Managing microservices within one cluster.	Service A in Cluster A communicates with Service B in Cluster B, both on the same hardware.	Service A in a private data center communicates with Service B in a public cloud.

Here are the key differences between Service Mesh and Service Interconnect to help clarify your architectural decisions.

Feature	OpenShift Service Mesh	Service Interconnect
Introduction	Centralized control for service interactions	Simplifies interconnection across environments
Architecture	Sidecar proxy model	Virtual network overlay with routers
Deployment	Container on Red Hat OpenShift	Container on Red Hat OpenShift, VMs, bare-metal
Security	Mutual TLS for pod-to-pod communication	Mutual TLS for router-to-router communication
Ownership	Managed by cluster administrators	Managed by development teams
Observability	Advanced metrics, logs, and tracing via Kiali	Basic visualization and logging
Ideal Use Cases	Traffic management, observability, A/B testing	Progressive migrations, interconnecting diverse platforms
Federation	Supports cross-cluster connectivity	No federation; focuses on interconnections
Environment Support	OpenShift 4.10 and later	OpenShift, RHEL, Kubernetes, VMs, bare-metal
Configuration Overhead	Requires Envoy proxy per application pod	One router per namespace
Traffic Management	Advanced capabilities	Basic interconnection
Key Considerations	Team skills, workload requirements, platform	Flexibility for dev team self-service