Problem
Networks receive packets from other networks. Normally a packet will contain the IP address of the computer that originally sent it. This allows devices in the receiving network to know where it came from, allowing a reply to be routed back (amongst other things).
However, a sender IP address can be faked ('spoofed'), characterising a Spoofing attack. This disguises the origin of packets sent, for example in a Denial-of-service attack.
Read more about this topic: Ingress Filtering
Famous quotes containing the word problem:
“The problem with marriage is that it ends every night after making love, and it must be rebuilt every morning before breakfast.”
—Gabriel García Márquez (b. 1928)
“[How] the young . . . can grow from the primitive to the civilized, from emotional anarchy to the disciplined freedom of maturity without losing the joy of spontaneity and the peace of self-honesty is a problem of education that no school and no culture have ever solved.”
—Leontine Young (20th century)
“Theology, I am persuaded, derives its initial impulse from a religious wavering; for there is quite as much, or more, that is mysterious and calculated to awaken scientific curiosity in the intercourse with God, and it [is] a problem quite analogous to that of theology.”
—Charles Sanders Peirce (1839–1914)