Cilium

Cilium uses eBPF - a Linux kernel technology - to implement Kubernetes networking, network policy enforcement, load balancing, and observability directly in the kernel, avoiding the performance overhead of traditional iptables-based networking. It's a CNCF graduated project that's become one of the most widely adopted Kubernetes CNI (networking) plugins.

Cilium is a fit for platform teams that want high-performance networking, fine-grained network security policy, and deep network observability for Kubernetes, complementing Istio (also in this catalog) - Cilium can operate at the networking layer alone or provide service-mesh capabilities without a sidecar proxy.