Metaswitch has released version 1.0 of its open source data center network virtualization system, called Project Calico.

First launched in beta in July of last year, Calico is a Layer 3 approach to network virtualization that aims to provide a lightweight, scalable alternative to Layer 2 VXLAN for virtual network functions, avoiding VXLAN's overlay and encapsulation requirements.

The system works for both virtual machines (VMs) and containers. Andy Randall, a senior vice president at Metaswitch, says that approach has begun to drive interest in Calico as Docker takes hold in the data center.

"People in IT departments are starting to think about the impacts of microservices," he says. "How do you define the policy for that kind of networking?"

OpenStack environments may be Calico's biggest opportunity to gain traction, with scalability concerns lingering around that cloud architecture's Neutron networking module.

Most of Project Calico's 19 Github contributors appear to be Metaswitch employees. It remains to be seen whether the project will gain broader community traction.

Separately, Metaswitch is also announcing today that it's teaming up with Mesosphere to integrate Calico with Apache Mesos, the Mesosphere Datacenter Operating System (DCOS), and other Mesosphere projects.