Big Switch Networks is the leading Open Software-Defined Networking (SDN) vendor. Big Switch Networks Open Software Defined Networking (SDN) architecture is built around the Big Network Controller, which provides a common data model and policy abstraction for all the network fabric elements. These universal network abstractions and the Big Network Controller leverage industry standards and open APIs to provide maximum deployment flexibility. The Big Network Controller enables a broad range of application support, including data center network virtualization.
Big Switch Networks Open Software Defined Networking (SDN) is based on a three-tier architecture
• Northbound Open APIs for application developers
• An open-core controller
• Southbound industry-standard data plane communication protocols.

1) Northbound Open APIs - Open APIs refer to the software interfaces in between the software modules of the controller platform and the SDN applications running atop the network platform. The Open SDN architecture focuses on Northbound APIs, which expose the universal network abstraction data models and functionality within the Big Network Controller for use by network applications. These interfaces are published and open to customers, partners, and the open source community for development. The Open APIs enable maximum utility of the Open SDN architecture through the ecosystem of customers and partners developing on the platform.
2) Open Core Controller – At the center of the Open SDN architecture is an open core controller named “Floodlight”, which maintains API consistency with the Big Switch Networks commercial controller – Big Network Controller. Applications written for Floodlight will work with Big Network Controller. Floodlight is distributed under Apache License Version 2.0, which provides customers and application developers with maximum investment protection since their SDN architecture will always remain independent of vendor interests.
3) Standards-based Southbound Protocols - Big Switch Networks focuses on standards-based connectivity for the “Southbound Protocols,” which define the control communications between the controller platform and data plane devices, including physical and virtual switches. While the majority of the Big Switch Networks’ current development efforts have been dedicated towards the OpenFlow protocol, the Open SDN architecture is flexible and can leverage other protocols in addition to OpenFlow. Support for a wide range of physical and virtual switches ensure that customers have maximum choice and flexibility designing and deploying their software-defined network.
