Software-Defined Networking Architecture for NoC-based Many-Cores
Marcelo Ruaro, Henrique Martins Medina, Alexandre M. Amory, Fernando Gehm Moraes · 2018
The Software-Defined Networking (SDN) is a communication paradigm adopted in computer networking. The SDN assumes simple and programmable routers, removing the control logic from the routers' level, and assigning it to a high-level controller (software), which is responsible for defining the path of the communication flows at run-time. The controller can implement different communication rules to define the paths, as Quality-of-Service (QoS), fault-tolerance, and security. Many-cores may adopt the SDN paradigm due to its advantages: reduced hardware complexity, high reusability, and flexible management of communication policies. However, the challenge to apply the SDN may be the overhead for defining the paths in software against hardware-based approaches. The goal of this paper is to show that SDN can be a viable alternative for NoC management in many-core systems. This work proposes a generic SDN architecture for many-cores, detailing both the hardware and software designs. We compare the quality of the proposal with a state-of-the-art search path mechanism (hardware implemented), in a QoS case-study providing Circuit-Switching (CS) for applications. Results show that the SDN paradigm achieves similar performance than the hardware-based technique regarding path length. Hardware implemented mechanisms present a reduced latency to establish the paths. As the path establishment occurs once for each application flow, results show that the search path latency of SDN is not an actual drawback, as it could be expected.