Date: Aug 13, 2013 8:20 PM
Author: Jonathan Crabtree
Subject: The Arithmetic of Scalar Multiplication on Elliptic Curve Cryptography
The Arithmetic of Scalar Multiplication on Elliptic Curve Cryptography: k times or k - 1 times?
Point 'addition' on elliptic curves is both commutative P + Q = Q + P and associative (P + Q) + R = P + (Q + R)
So when point P on an elliptic curve is multiplied by a scalar k, should it be explained as 'p added to itself k - 1 times' or 'p added to itself k times'?
Which definition of scalar multiplication on elliptic curves is right and why? Please make your explanation as simple as possible!
k - 1 times
If point P on EC is added to itself (k-1) times then we obtain a new point kP on elliptic curve and kP is termed as the scalar multiplication of point P by scalar k.
The fundamental operation for generating a finite abelian group over an elliptic curve is the addition of two points on it. If point P on EC is added to itself (k-1) times then we obtain a new point kP on elliptic curve and kP is termed as the scalar multiplication of point P by scalar k.
Point iteration is adding a point to itself multiple times. If a point is added to itself k-1 times, where k is a positive integer then point iteration is represented as: [k]P=P+P+ ..+P (k-1 times).
Scalar point multiplication is the major building block of all elliptic curve cryptosystems, an operation of the form where k is a positive integer and P is a point on the elliptic curve. Calculating gives the result of adding the point P to itself for exact k-1 times, which results in another point Q on the elliptic curve. AND ALSO Scalar point multiplication is one of the major buildings of ECC block. An operation of form where is a positive integer, P is a point on the curve. The idea is adding the point P to itself k - 1 times to get the resulted point Q.
... multiplication operation computes the multiple Q = kP, which corresponds to adding P to itself k - 1 times
Cryptographic schemes based on ECC rely on scalar multiplication of elliptic curve points. As before given an integer k and a point P... scalar multiplication is the process of adding P to itself k times.
The scalar integer multiplication of an elliptic curve point, P is defined as the process of adding P to itself k times. Q = k P.
Let k be a positive integer and P a point on an elliptic curve. Then elliptic curve scalar multiplication is the operation that computes the multiple Q = kP, defined as the point resulting of adding P to itself k times.
Scalar Multiplication. Adding a point P to itself k times is called scalar multiplication or point multiplication, and is denoted as Q = kP
Given an elliptic curve E and a point P on the curve, the point Q is calculated by point scalar multiplication where the point P is added to itself k times
So which definition of scalar multiplication on elliptic curves is right and why?
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Message was edited by: Jonathan Crabtree to include a P.S.