Tigera has been working with Microsoft and their joint customers over the past few years to bring Project Calico to the Windows platform. The company has also seen increasing demand for Windows nodes ever since the release of Kubernetes 1.14.
Most enterprises have a Windows footprint, and Windows workloads are increasingly being modernized and migrated to containers and orchestrated with Kubernetes. Enterprise users want to deploy a single solution for network security that works across both Linux and Windows workloads.
Open-sourcing Calico for Windows is claimed to provide those users with the best and only solution available, and for free.
Calico offers a pluggable data plane supporting Linux, eBPF for modern Linux kernels, and Windows; future-proofing their decision to go with Calico.
Calico currently powers more than 200,000 known clusters across over a million nodes in 166 countries worldwide.