2/07/2009

An Intresting Cryptography Story

据solidot报道:有位小伙心仪的对象是个学心理学又喜欢研究古典密码学的姑娘,在向其表白后,收到一段密文,说是经过五层加密的结果,其明文就是她对这段缘份的答复。小伙子束手无策时在百度的密码吧上求助,得到众网友的热心回复......

Here is the whole decryption process

the original ciphertext:

****-/*----/----*/****-/****-/*----/---**/*----/****-/*----/-****/***--/****-/*----/----*/**---/-****/**---/**---/***--/--***/****-/

Layer 1 - Morse Coding

Rule: standard Morse Decoding

Output: 41 94 41 81 41 63 41 92 62 23 74

Layer 2 - Telephone Keypad Coding
Rule: mn stands for the n-th letter on the m-th key on telephone keypad (see ITU-E.161 standard and ISO/IEC9995 standarad)

Output: G Z G T G O G X N C S

Layer 3 - Computer Keyboard Coding

Rule: QWERT -> ABCDE and so on ... (see Keyboard Layout and ISO/IEC9995 standarad)

Output: O T O E O I O U Y V L

Layer 4 - Route Cipher

Rule: one of the transportion cipher method that belongs to classical cipher, in which plaintext is written down in row order but read off in column order

first, break it into two lines:
O T O E O I
O U Y V L

then remerge them using another order(up->down first, left->right second)

Output: OOTUOYEVOLI

Layer 5 - inverse transportiong

Rule: read off the ciphertext from the end to beginning

Output:
I LOVE YOU TOO

从加密方法来看,全是古典密码学中基本的的替换法转置法。但是经过这么多层层嵌套组合,要想得到最后的明文,还是得花点功夫连试带猜才行。

相关报道
百度贴吧原贴
Solidot原文
布丁通讯的报道
百度空间描述的详细过程

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