ECE4253 Digital Communications | |
Department of Electrical and Computer Engineering - University of New Brunswick, Fredericton, NB, Canada | |
In the case of books, the International Standard Book Number (ISBN-13) adds a single check digit to create a 13-character book number. This standard replaced the old 10-digit version in January, 2007. While the new system allows for more books, it is weaker as an error control algorithm; in particular, certain digit transpositions are not caught.
Specifically, exchanging the adjacent digit pairs (0,5) (1,6) (2,7) (3,8) (4,9) in either order would not be detected.
9 7 8 1 1 1 8 1 1 5 3 9 8 x1 x3 x1 x3 x1 x3 x1 x3 x1 x3 x1 x3 x1 -- -- -- -- -- -- -- -- -- -- -- -- -- 9 + 21 + 8 + 3 + 1 + 3 + 8 + 3 + 1 + 15 + 3 + 27 + 8 = 110 |
There is a one-in-ten chance that a totally random number will pass this simple validity test.
Check an ISBN-13 number by entering it in the box below. Dashes may be used between digits as desired.
2024-07-14 16:14:49 ADT
Last Updated: 2015-03-02 |
Richard Tervo [ tervo@unb.ca ] | Back to the course homepage... |