1. Botnets remain a leading threat, 2013 (blogs.mcafee.com/business/security-connected/tackling-the-botnet-threat).
2. Verisign Q1 2016 DDoS trends, 2016 (https://www.verisign.com/assets/report-ddos-trends-Q12016.pdf).
3. Akamai detected over 400 reflection DDoS attacks leveraging DNSSEC protocol, 2016 (http://news.softpedia.com/news/akamai-detected-over-400-reflection-ddos-attacks-leveraging-dnssec-protocol-500497.shtml).
4. Technical details behind a 400 Gbps NTP amplification DDoS attack, 2014 (https://blog.cloudflare.com/technical-details-behind-a-400gbps-ntp-amplification-ddos-attack/).
5. Arbor networks 11th annual worldwide infrastructure security report, 2016 (https://www.arbornetworks.com/images/documents/WISR2016_EN_Web.pdf).