Description
QUAD relies on the iteration of a randomly chosen multivariate quadratic system S=(Q1, ..., Qm) of m=kn equations in n unknowns over a finite field GF(q). The keystream generation process simply consists in iterating the three following steps in order to produce (k -1) n GF(q) keystream values at each iteration.
- Compute the kn-tuple of GF(q) values S(x) = (Q1(x),..., Qkn(x)) where x is the current value of the internal state;
- Output the sequence (Qn+1(x),..., Qkn(x)) of (k-1)n GF(q) keystream values
- Update the internal state x with the sequence of n GF(q) first generated values (Q1(x),..., Qn(x))
QUAD is a modern stream cipher, i.e. it uses a key and an initialisation value (IV) to produce a keystream sequence. A Key and IV setup is also defined which also rely on multivariate quadratic system.
Read more about this topic: QUAD (cipher)
Famous quotes containing the word description:
“An intentional object is given by a word or a phrase which gives a description under which.”
—Gertrude Elizabeth Margaret Anscombe (b. 1919)
“The great object in life is Sensation—to feel that we exist, even though in pain; it is this “craving void” which drives us to gaming, to battle, to travel, to intemperate but keenly felt pursuits of every description whose principal attraction is the agitation inseparable from their accomplishment.”
—George Gordon Noel Byron (1788–1824)
“I was here first introduced to Joe.... He was a good-looking Indian, twenty-four years old, apparently of unmixed blood, short and stout, with a broad face and reddish complexion, and eyes, methinks, narrower and more turned up at the outer corners than ours, answering to the description of his race. Besides his underclothing, he wore a red flannel shirt, woolen pants, and a black Kossuth hat, the ordinary dress of the lumberman, and, to a considerable extent, of the Penobscot Indian.”
—Henry David Thoreau (1817–1862)