The Open Compute Project (OCP) is a collaborative community focused on redesigning hardware technology to efficiently support the growing demands on compute infrastructure.

http://www.opencompute.org/

Open Network Linux is a Linux distribution for "bare metal" switches, that is, network forwarding devices built from commodity components. ONL uses ONIE to install onto on-board flash memory. Open Network Linux is a part of the Open Compute Project and is a component in a growing collection of open source and commercial projects."

www.opennetlinux.org

Project Atrium is an open source SDN distribution - a vertically integrated set of open source components which together form a complete SDN stack. It’s goals are threefold: 1) Close the large integration-gap of the element 2) Overcome a massive gap in interoperability 3) Work closely with network operators on deployable use-cases,

https://github.com/onfsdn/atrium-docs/wiki

OpenSwitch is Community-Based, Open Source, Full-Featured Network Operating System.

http://www.openswitch.net/

Open Networking Foundation (ONF) is a user-driven organization dedicated to the promotion and adoption ofSoftware-Defined Networking (SDN) through open standards development. SDN is a new approach to networking in which network control is decoupled from the data forwarding function and is directly programmable. The result is an extremely dynamic, manageable, cost-effective, and adaptable architecture that gives administrators unprecedented programmability, automation, and control. Implementing SDN via an open standard enables extraordinary agility while reducing service development and operational costs, and frees network administrators to integrate best-of-breed technology as it is developed.

https://www.opennetworking.org/index.php