The Security Flag in the IPv4 Header
NOTE: This was an April Fool's joke :)
Firewalls, packet filters, intrusion detection systems, and the like often have difficulty distinguishing between packets that have malicious intent and those that are merely unusual. The problem is that making such determinations is hard. To solve this problem, we define a security flag, known as the "evil" bit, in the IPv4 header. Benign packets have this bit set to 0; those that are used for an attack will have the bit set to 1.
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