Kong vs linkerd: What are the differences?

Introduction

Kong and Linkerd are both popular service mesh solutions that help manage the complexity of microservices architectures. However, there are key differences between the two.

1. Deployment and Architecture: Kong is an API gateway and service mesh that is deployed as a standalone system, usually through Docker or Kubernetes. It acts as a centralized proxy for all incoming requests. In contrast, Linkerd is a lightweight service mesh that operates as a sidecar proxy, deployed alongside each microservice. This allows Linkerd to provide observability and control at the application level, while Kong operates at the infrastructure level.

2. Service Discovery and Load Balancing: Kong uses a plugin system to handle service discovery and load balancing. With Kong, you can configure plugins to perform DNS-based service discovery and load balancing. In contrast, Linkerd uses a decentralized architecture with a sidecar proxy for each microservice. This allows Linkerd to automatically discover and load balance traffic without any additional configuration.

3. Integration and Extensibility: Kong provides a rich set of plugins and integrations, making it highly extensible and customizable. It supports authentication, rate limiting, transformation, and caching, among other features. On the other hand, Linkerd focuses more on observability and reliability, providing features like request tracing, metrics, and circuit breaking. While Linkerd supports some extensibility, it has a narrower focus compared to Kong.

4. Ease of Use and Learning Curve: Kong offers a comprehensive set of features, but this can make it more complex to set up and configure. It requires a certain level of expertise to effectively use and manage Kong as an API gateway and service mesh. Linkerd, being lighter weight and more focused, has a smaller learning curve and can be easier to integrate into existing microservices architectures.

5. Community and Support: Kong has a larger and more established community compared to Linkerd. With a larger user base and more contributors, Kong enjoys a wider range of community-supported plugins and extensions. Linkerd, while growing in popularity, may have a more limited community and plugin ecosystem.

6. Vendor and Commercial Support: Kong is backed by Kong Inc., a company that offers a commercial version with additional enterprise features and support. This can be beneficial for organizations looking for reliable commercial support and additional functionality. Linkerd, in comparison, is an open-source project primarily maintained by the Cloud Native Computing Foundation (CNCF) without a direct commercial entity backing it.

In summary, Kong is a robust API gateway and service mesh solution that operates as a standalone system, while Linkerd is a lightweight, sidecar-based service mesh focused on observability and reliability. Kong offers more extensibility and customization options, but has a steeper learning curve, while Linkerd is simpler to integrate but with a narrower set of features. Each solution has its strengths and best fits different use cases and deployment scenarios.