Ambassador vs Consul: What are the differences?

Key Differences between Ambassador and Consul

Ambassador and Consul are both popular service mesh tools used in modern cloud-native applications. While they share some similarities in their features and purposes, there are key differences that set them apart. Here are six important distinctions between Ambassador and Consul:

1. Protocol Support: Ambassador primarily supports HTTP/1.1 and HTTP/2 protocols and is designed to act as a gateway for routing, load balancing, and authentication of HTTP traffic. On the other hand, Consul provides service discovery, distributed key-value store, and health checking capabilities, with support for various protocols like TCP, DNS, and gRPC in addition to HTTP.

2. Configuration Approach: Ambassador uses a declarative approach for configuration, where you define the desired state of your services and the router manages the connections accordingly. In contrast, Consul employs a more dynamic approach with a focus on service discovery and automatic configuration using a service registry. It dynamically updates the services and routes based on changes in the network.

3. Scaling Consideration: When it comes to scaling, Ambassador is horizontally scalable, allowing you to add more instances to handle increased traffic. Ambassador can be easily integrated with Kubernetes to dynamically scale based on demand. Consul, on the other hand, is designed to handle large-scale deployments with thousands of services and nodes. It provides scalable DNS resolutions and has a hierarchical key-value store for efficient querying.

4. Traffic Management Capabilities: Ambassador is specifically built for routing and load balancing of HTTP traffic. It provides advanced traffic management features such as rate limiting, circuit breaking, and retries. Consul, besides service discovery, offers additional traffic management features like connect and intention-based routing. Consul enables secure communication between services by establishing encrypted communication channels.

5. Community and Ecosystem: Ambassador has a large and active open-source community with extensive documentation and support. It integrates well with Kubernetes and is widely used in cloud-native environments. Consul, on the other hand, is developed by HashiCorp and is part of a broader ecosystem of HashiCorp tools. It is compatible with various infrastructure providers and has a robust set of plugins and integrations.

6. Control Plane Architecture: The architecture of Ambassador and Consul differs in terms of the control plane approach. Ambassador relies on a single instance acting as the controller (Ambassador Edge Stack), which manages the routing and configuration. Consul, on the other hand, adopts a distributed approach with multiple Consul server instances forming the control plane. This distributed model provides higher availability and fault tolerance.

In summary, Ambassador and Consul have distinct characteristics that cater to different requirements. Ambassador focuses on HTTP traffic routing, load balancing, and authentication, while Consul offers service discovery, dynamic configuration, and traffic management capabilities for various protocols. The choice between Ambassador and Consul depends on specific use cases, infrastructure, and architectural preferences.