Cilium vs Weave: What are the differences?

Introduction:

Cilium and Weave are both networking solutions for containerized environments, but they have key differences in their approach and features.

1. Built-in protection: Cilium is primarily focused on enhancing network security by integrating with various externals systems such as Kubernetes Network Policies, Istio, and Envoy. It provides deep visibility into application and network behavior, enabling the enforcement of fine-grained security policies. Weave, on the other hand, focuses on providing a simple and flexible networking solution without built-in security features.

2. Data plane technology: Cilium utilizes Linux kernel BPF (Berkeley Packet Filter) technology to provide efficient packet filtering and network visibility. It leverages BPF to implement advanced networking features like load balancing, network address translation, and service discovery. In contrast, Weave uses a virtual network overlay approach, encapsulating traffic within an overlay network. It does not rely on in-kernel technologies like BPF.

3. Service mesh integration: Cilium natively integrates with popular service mesh solutions like Istio and Linkerd. It enhances their functionality by providing advanced networking capabilities and security features. Weave does not have direct integration with service mesh frameworks, making it suitable for simpler networking requirements.

4. Network policy control: Cilium offers powerful network policy control capabilities that operate at the application layer, enabling fine-grained security and network policies. It allows policies to be defined based on application identity and enforce them across multiple communication protocols. Weave focuses on network isolation and DNS-based service discovery but lacks the advanced application-level network policy control provided by Cilium.

5. Scalability and performance: Cilium's BPF-based approach enables it to achieve high-performance networking and scale to large container deployments. It leverages kernel-level functionality to minimize latency and efficiently handle network traffic. Weave's overlay network approach may introduce additional latency and does not offer the same level of scalability and performance as Cilium.

6. Support for cloud-native environments: Cilium is designed specifically for cloud-native environments like Kubernetes and is tightly integrated with container orchestration platforms. It offers seamless integration with Kubernetes API, making it easier to manage networking configurations. While Weave also supports Kubernetes and other container platforms, it does not have the same level of integration and native support for cloud-native environments as Cilium.

In Summary, Cilium provides built-in network security, leverages BPF technology, integrates with service meshes, offers powerful network policy control, ensures high scalability and performance, and supports cloud-native environments. Weave, on the other hand, focuses on simplicity and flexibility in networking without built-in security features, uses virtual network overlays, lacks native service mesh integration, offers limited network policy control, and may have performance limitations in larger deployments.