Introduction 

SDN-IP is an ONOS application that allows a Software Defined Network to connect to external networks on the Internet using the standard Border Gateway Protocol (BGP). Externally, from a BGP perspective, the SDN network appears as a single Autonomous System (AS) that is behaving as the traditional ASs. Within the AS, the SDN-IP application provides the integration mechanism between BGP and ONOS. At the protocol level, SDN-IP behaves as a regular “BGP speaker”. From ONOS perspective, it’s just an application that uses the ONOS services to install and update the appropriate forwarding state in the SDN data plane.

Architectural goals

SDN-IP has been designed with the following goals in mind:

• Compatibility: SDN-IP can be integrated with networks that already use BGP - externally, internally, or both.
• Operational flexibility: SDN-IP can run on one or multiple ONOS instances. Moreover, SDN-IP can be used in a variety of BGP deployment scenarios: full-mesh BGP, BGP Route Reflectors, BGP confederations, and with BGP Route Servers.
• High availability: SDN-IP provides HA within the application itself. The SDN-IP service keeps working seamlessly, as long as there is at least one instance of the SDN-IP application running. In addition, SDN-IP leverages the HA mechanisms provided by ONOS for maintaining a consistent forwarding state in the data plane.
• Scalability: Large-scale Software Defined Networks can be controlled by using BGP-based Confederations and multiple ONOS clusters, each running SDN-IP.
• Protocol compatibility and vendor independence: SDN-IP relies on the standard BGP protocol for exchanging network information, and does not require any proprietary or vendor-specific extensions.

Overview