In the experimental evaluation, is the implementation based on a simulation platform, or is it conducted in a real network environment? If it’s simulation-based, which simulator did you use?
The experiments are simulation-based, not conducted in a real network environment.
Specifically, the authors use Mininet, a network emulator that runs on a commodity Linux server. Mininet emulates the GÉANT backbone topology (23 nodes, 74 directed links) in software, and the Ryu SDN framework serves as the controller platform. BRIGHT and all baseline algorithms are implemented as Ryu controller applications running on top of this emulated environment.
While Mininet provides realistic SDN behavior including actual OpenFlow message exchanges, it is still an emulation rather than a true physical network deployment. The authors acknowledge this limitation and mention validating on larger-scale testbeds and real controllers (ONOS, OpenDaylight) as future work.
