There is a new, emerging type of switch or router hardware called a “white box” that may be used in the research and education community. White boxes can now provide a “forwarding plane” at 100GbE line rate at an affordable CAPEX and are able to run a variety of network OS. Some of them also offer the ability to be programmable thanks to a high-level abstraction language called P4 (Programming Protocol-independent Packet Processors). This paves the way to create an open-source router software platform that could be tuned and optimized for research and education. Moreover, it allows bringing back network innovation within research and education by allowing researchers to quickly test new paradigms on hardware in the NREN context.
Router for Academia Research and Education (RARE) is a project that assesses the validity of running a control plane software on top of a P4 data plane hardware in the NREN context. The project proposes coupling a control plane based on the FreeRTR open-source software platform to a P4-based data plane developed by the RARE team. The activity aims to integrate different software modules for the necessary three building blocks: the control plane, the P4 data plane and communication between the control plane and P4 data plane. A key part of the work consists of enabling the control plane software to pilot the data plane via a programmatic interface written in the P4 language.
During the project’s first year of integration/development effort, the RARE team managed the integration using an open-source control plane FreeRtr, which provides a rich feature set of routing functionalities. Among them, IPv4, IPv6, MPLS, SR-MPLS, L3VPN, XConnect, VPLS, EVPN, 6VPE, SRv6 were successfully integrated into P4 target architectures such as Open Source BMv2 and BAREFOOT bf_switchd. A demonstration of Segment Routing is available and documentation has been produced. The success of this integration has unlocked the doors to several use cases: CPE, Provider and Provider Edge router, Internet eXchange Point, Data Center…
The programmability of RARE allows customisation of router software. For instance, if there is no need for MPLS, RARE can be compiled without the MPLS module for more light-weight software. At the same time, if one wanted to implement a new protocol, it would be feasible to write the control plane part and potentially the data plane part as well. This customisation permits distributing the switch capacities depending on the customer use case thus maximizing the return on investment.
More importantly, thanks to P4, RARE as a routing platform can be extended programmatically. For example, a “scrubbing” module can be programmed alongside RARE in order to provide an anti-DDOS mitigation component or can be used for In-band Telemetry (INT) https://wiki.geant.org/display/SIGNGN/2nd+SIG-NGN+Meeting.
A P4 European testbed is being rolled out: eight P4-enabled switches interconnected by GÉANT are currently under deployment to create a RARE network, in order to demonstrate these features at a European level. Four switches are provided by GÉANT in GN4-3 WP6-T1, 1 by Jisc, 2 by RENATER and 1 by SWITCH.
In parallel, the WP6 Task1 team is pushing to raise a community around the RARE initiative and further encouraging network innovation within the European research and education community.
