To protect the operation of infrastructure, or the operating system against DDoS attacks from the Internet, a technical system in the hardware or in the kernel of an e-mail gateways.

摘要

Described is following a technical system in the hardware or in the kernel of email gateways to protect against overload and failure situations, especially against DDoS attacks from the Internet. The system works without redirection of connections to another system, without any markings, the IP header, without modification, and the blocking of SMTP connections in conjunction with a kernel IP Whitelist. The system only applies to the SMTP protocol and general protocols that are based on the latter, as SMTPS. Massive congestion situations caused by such DDoS attacks, or even many simultaneous connections from different IP addresses, claiming the software or hardware at the same time, can halt of software or hardware or extremely slow response times from result affected operating system and the software being run.