For more information, please refer to the following links:
- https://www.nanog.org/sites/default/files/tuesday_general_ddos_ryburn_63.16.pdf
- https://conference.apnic.net/data/37/apricot-2014-wei-yin-scalable-ddos-mitigation-using-bgp-flowspec_1393312254.pdf
- https://tools.ietf.org/html/rfc5575
- https://www.opennetworking.org/sdn-definition/
- https://www.sdxcentral.com