Stopping a BitTorrent DDoS attack

http://blog.carlesmateo.com/2015/01/23/stopping-a-bittorrent-ddos-attack/
http://blog.carlesmateo.com/2015/02/01/stopping-definitively-the-massive-distributed-dos-attack/
http://serverfault.com/questions/656093/mod-security-block-requests-by-http-host-header
http://serverfault.com/questions/656189/strange-bittorrent-log-on-my-server