| Presentation | 2006-07-20 Possibility of the Key Recovery Attack against Py Takanori ISOBE, Toshihiro OHIGASHI, Hidenori KUWAKADO, Masakatu MORII, |
|---|---|
| PDF Download Page |  PDF download Page Link |
| Abstract(in Japanese) | (See Japanese page) |
| Abstract(in English) | Biham and Seberry have submitted the stream cipher Py to the ECRYPT Stream Cipher Project (eSTREAM). In this paper, we present two useful methods for the key recovery attack against Py. First, we show the method for finding a secret key from a part of the initial state of Py. In this method, the required data size of the initial state is one fifth or less compared with the method proposed by Kogiso, Shimoyama, and Chao. And, the required data size of the initial state by our method is almost equal to that of the secret key. Additionally, we show the relation between the required data size of the initial state and the rate of the recoverable keys by our method. Second, we show the method to guess a part of the initial state from other part of the initial state with high probability. This method can reduce the computational time for reconstructing the initial state from the keystream. |
| Keyword(in Japanese) | (See Japanese page) |
| Keyword(in English) | stream cipher / Py / key recovery attack / key scheduling algorithm |
| Paper # | ISEC2006-28,SITE2006-25 |
| Date of Issue |
| Conference Information | |
| Committee | SITE |
|---|---|
| Conference Date | 2006/7/13(1days) |
| Place (in Japanese) | (See Japanese page) |
| Place (in English) | |
| Topics (in Japanese) | (See Japanese page) |
| Topics (in English) | |
| Chair | |
| Vice Chair | |
| Secretary | |
| Assistant | |
| Paper Information | |
| Registration To | Social Implications of Technology and Information Ethics (SITE) |
|---|---|
| Language | JPN |
| Title (in Japanese) | (See Japanese page) |
| Sub Title (in Japanese) | (See Japanese page) |
| Title (in English) | Possibility of the Key Recovery Attack against Py |
| Sub Title (in English) | |
| Keyword(1) | stream cipher |
| Keyword(2) | Py |
| Keyword(3) | key recovery attack |
| Keyword(4) | key scheduling algorithm |
| 1st Author's Name | Takanori ISOBE |
| 1st Author's Affiliation | Graduate School of Science and Technology, Kobe University() |
| 2nd Author's Name | Toshihiro OHIGASHI |
| 2nd Author's Affiliation | Graduate School of Science and Technology, Kobe University |
| 3rd Author's Name | Hidenori KUWAKADO |
| 3rd Author's Affiliation | Faculty of Engineering, Kobe University |
| 4th Author's Name | Masakatu MORII |
| 4th Author's Affiliation | Faculty of Engineering, Kobe University |
| Date | 2006-07-20 |
| Paper # | ISEC2006-28,SITE2006-25 |
| Volume (vol) | vol.106 |
| Number (no) | 174 |
| Page | pp.pp.- |
| #Pages | 8 |
| Date of Issue | |