Cilium 1.20, released on September 14, 2026, turns the Gateway API into a full traffic-management layer and finally closes the IPv6 gap in ENI mode on AWS. Teams migrating off ingress-nginx or extending their CNI now have a concrete reason to move.

Lambda engineers detail how they replaced an iptables-based packet counter, unable to scale to IPv6, with an eBPF and Rust pipeline that logs every flow across thousands of Firecracker microVMs per host. The lesson outlives AWS: at multi-tenant density, network bookkeeping must be nearly free and provably correct.

Released on July 29, 2025, Cilium 1.18 ships Load Balancing redesign, native overlay encryption, ingress bandwidth control, and sidecar-free mTLS. One year later, this version marks the definitive shift from CNI to complete network platform.

iptables is 25 years old in 2026 and relies on O(n) sequential rule chains that collapse at a few thousand entries. eBPF injects verified, JIT-compiled bytecode directly into the Linux kernel, and Cilium builds on that to route, secure, and observe Kubernetes traffic without kube-proxy.