Hello I have tried to get in contact with China Telecom and Korea Telecom through their abuse emails listed under the regional registry here asking them to block ports used in a large >10 gbit DDoS reflection attack.
The China Telecom abuse email "anti-spam@ns.chinanet.cn.net" does not work. I get a 550 invalid recipient. There is no response from Korea Telecom's abuse email.
Anyone have any suggestions on how to get them to respond?