Calico Open Source vs kube-network-policies

Calico Open Source provides networking, network security, and observability for Kubernetes across multi-cloud, hybrid-cloud, and on-premises environments. It supports container, virtual machine, and bare-metal workloads with a shared security policy framework. The policy engine implements Kubernetes network policy features including AdminNetworkPolicy and BaselineAdminNetworkPolicy. Policies can use tiers, deny and log actions, NetworkSets, and cluster-wide global rules; Staged Policies allow teams to assess behavior before applying enforcement. Listed data planes include eBPF, iptables, nftables, Windows, and VPP. Whisker provides a visual way to view flow logs and analyze network communication. Calico can also manage WireGuard tunnels to encrypt pod traffic between Kubernetes nodes. Calico Ingress Gateway provides traffic control, load balancing, and ingress policy enforcement. The free plan includes unlimited clusters, with in-memory data retention and community-driven support and maintenance. Tigera describes deployments ranging from 10 to 10,000 or more nodes.

kube-network-policies is a free, open-source userspace implementation of Kubernetes network policies for Linux. It uses Linux NFQUEUE and nftables to capture and evaluate network traffic in userspace. The project supports standard Kubernetes NetworkPolicy, AdminNetworkPolicy (ANP) and BaselineAdminNetworkPolicy (BANP). It can identify packets from pods targeted by active policies and capture those selectively; enabling ANP or BANP disables that optimization and diverts all node traffic to userspace for evaluation. Its documented evaluation pipeline checks logging, Admin Network Policy, standard NetworkPolicy, Baseline Admin Network Policy, then allows traffic by default. ANP and CNP can match external domain names using an in-memory cache of DNS A and AAAA answers. Structured JSON logs aid troubleshooting, and the PolicyEvaluator plugin pipeline can take custom validation logic. Installation instructions cover raw Kubernetes manifests and Helm. The local development setup uses KIND and lists Docker, KIND and kubectl as prerequisites. ANP or BANP also require experimental Network Policy API CRDs before deployment. The project lists an Apache-2.0 license and directs users to the Kubernetes #sig-network Slack channel and mailing list for maintainers.