OpenDaylight

OpenDaylight is an open source software defined networking platform built around a controller that manages heterogeneous networks through a single control point without vendor lock in. That independence from any one hardware manufacturer is the project's founding purpose.

Protocol breadth is the practical expression of it. The southbound plugin architecture supports NETCONF, BGP-LS, PCEP, OVSDB, LISP, SNMP and more, which is what allows a single controller to speak to equipment from different vendors and different generations. Most real networks are exactly that mixture, accumulated over years of procurement.

The architecture is layered and extensible, separating applications from protocols through a model driven service abstraction layer known as MD-SAL. Northbound REST APIs expose network state to applications, so software can query and act on the network without understanding the protocols underneath.

Scale is carrier grade by design. Built in clustering, sharded data stores and leader based consensus let OpenDaylight scale horizontally across nodes, and the project reports production deployments managing thousands of network devices with sub second convergence. As an open source project there is no licence cost, with expenditure falling on infrastructure and the engineering skill to operate it.