CNI Comparison 2026

Calico, Cilium, AWS VPC CNI. The 2026 decision.

Cilium

The CNI (Container Network Interface) plugin handles pod networking in Kubernetes. The choice affects security, performance, and operational characteristics. Cilium, Calico, and the cloud-native CNIs are the leading options; the right choice depends on the team's needs.

What Cilium provides:

• eBPF.: Cilium uses eBPF for packet processing. The technology is modern; performance is excellent; the depth of visibility is significant.
• Advanced features.: Network policies, identity-based security, transparent encryption, observability. Cilium's feature set is broader than traditional CNIs.
• Best for security-focused.: Teams with strong security requirements benefit from Cilium's identity-based policies. The security model goes beyond traditional CNI offerings.
• Or large clusters.: Cilium's eBPF-based approach scales well. Large clusters with complex network policies operate more efficiently.
• Hubble for observability.: Cilium's Hubble component provides network observability. Service maps, flow logs, network metrics all are available; the visibility is significant.

Cilium is the right choice for security-focused or large clusters. The advanced features justify the additional complexity.

Calico

Calico is the mature, widely-deployed CNI. The feature set is broad; the operational story is well-understood; most teams default to Calico without trouble.

• Mature.: Calico has been the dominant CNI for years. The codebase is stable; the operational story is well-documented; the community is large.
• Broad support.: Calico runs everywhere. Cloud, on-prem, edge, Kubernetes distributions all support it. The team's environment is likely supported.
• Best for most teams.: The default choice for many Kubernetes deployments. Familiar to operators; comprehensive in features; the safe choice.
• Multiple data planes.: Calico supports multiple data planes: standard Linux iptables, eBPF, VPP. The team can choose the data plane that fits their needs.
• Network policy support.: Calico's network policy implementation is comprehensive. Standard Kubernetes network policies plus Calico's extended policies cover most use cases.

Calico is the safe default. The maturity and broad support make it the right choice for most teams.

AWS VPC CNI

The AWS VPC CNI is the EKS default. Pods get VPC IPs; the integration with AWS networking is tight; the trade-off is some advanced features that other CNIs offer.

• AWS-native.: The CNI integrates with AWS VPC. Each pod gets a real VPC IP; security groups apply at the pod level; the AWS-native patterns work directly.
• Tight integration.: AWS services that expect VPC IPs (Network Load Balancer, ALB target groups, security groups) work directly with pods. The pod is a first-class VPC resident.
• EKS default.: EKS uses the AWS VPC CNI by default. The team gets it without configuration; the operational story is well-supported by AWS.
• Works for most.: The default is sufficient for most teams. Tight AWS integration plus standard Kubernetes networking covers most use cases.
• IP allocation considerations.: Pod IPs come from VPC subnets. The team's VPC IP planning must account for pod density; with prefix delegation, the IP consumption is manageable.

CNI comparison is one of those Kubernetes architectural decisions that affects networking and security. Nova AI Ops integrates with cluster networking, surfaces traffic patterns, and helps teams understand whether their CNI choice matches their actual networking requirements.