Chapter 1 : Introduction 1. Given the keying sequence: 18 18 0 20 7 13 19 19 25 7 25 4 10 10 19 11 20 24 8 13 Cipher the following message: YOU Z CANNOT Z HURT Z ME Remarks: a) One uses the "Z" letter in place of space. b) One presents cipher text message by 5 letters groups. 2. Given the plain and cipher text: Plain: WEZAR EZNOT ZAZCL ONEZZ Cipher: TMWIV AJGEC KTAXY KWGUH Calculate the keying sequence. 3. Given the keying sequence: 14 13 17 23 17 12 5 10 3 21 1 17 24 3 18 10 15 18 2 18 Decipher the following message: AIOSY TWQEV TQFDE VPGBV 4. Cipher the text "AAAAA". The key table is given: wheel 26, Lugs: 2, Pins: __CDEF_H_JK___OP__S_U__XYZ wheel 25, Lugs: 5, Pins: _BC_E___I__LM__P_RS_U___Z wheel 23, Lugs: 1, Pins: A__DEFGHI_K___O_Q_ST_V_ wheel 21, Lugs: 3, Pins: _BC_EF___J__M_OP_R_TU wheel 19, Lugs: 9, Pins: ABC__F_H_J__M_O___S wheel 17, Lugs: 7, Pins: __C__FGH_J_LM_OP_ External Key: LLKJIH (With this Key, the actives Pins are: AAAAAA) 5) Decipher the cipher text "WGBQM". External Key (message key): "PEOPLE" Key table of the day: ------------------------------- NR LUGS 1 2 3 4 5 6 ------------------------------- 01: 2-5 _ _ A _ A _ 02: 5-6 _ B _ B B _ 03: 1-0 C C _ C C C 04: 1-0 D _ D _ _ _ 05: 2-0 E E E E _ _ 06: 2-0 F _ F F F F 07: 2-0 _ _ G _ _ G 08: 2-0 H _ H _ H H 09: 3-0 _ I I _ _ _ 10: 0-4 J _ _ J J J 11: 0-4 K _ K _ _ _ 12: 0-4 _ L _ _ _ L 13: 0-5 _ M _ M M M 14: 0-5 _ _ _ _ _ _ 15: 0-5 O _ O O O O 16: 0-5 P P _ P _ P 17: 0-5 _ _ Q _ _ _ 18: 0-5 _ R _ R _ 19: 0-5 S S S _ S 20: 0-5 _ _ T T 21: 0-5 U U _ U 22: 0-6 _ _ V 23: 0-6 _ _ _ 24: 0-6 X _ 25: 0-6 Y Z 26: 0-6 Z 27: 0-6 ------------------------------- Shift: Z, 26 letters Check: EVJUL MFNQS UCLAM RJLML NLUHD B ------------------------------- 6. Decipher the cipher text: DSVMA RMAIL NVAWL AZHAG SVAIL NZMHX The message begins by the word "WHEN". 7. The following four messages have been enciphered with the same key. The 3rd message begins with the plaintext word "BIRDS". Read the messages. No. 1 - FZGYU LMIJE LMXSS EXHNG SJFKG MOEZO AOUGY No. 2 - FZGYR ZFDRM MZJRV TQZGV GRTQS PTXAG ONTGY No. 3 - XYTUR QLCSW LTBYG QXHNU OVQZA AEXNR HBGGY No. 4 - YHVTW CBIZW PUCZR FCYNK VWFLA PSMEG LGYGY Hint 1 (in caesar cipher): ILUVW SURSDEOH ZRUG : ZKHHO (LQ VHFRQG PHVVDJH) Hint 2 (in caesar cipher): VHFRQG SUREDEOH ZRUG : SHQQB 8. The following three messages have been enciphered with the same key. The last message contains the word "CLOSE". Read the messages. No. 1 - XHVCY BYSJY ELSHV KZIHI VJBXJ MYVSU ELSUI QHLAP XVJBG No. 2 - QSIFZ EXASX WVGRP RGBFG VBATL WYWND SPART JNQWU FOYPR No. 3 - NCTUA VRAMZ VVSPB KXPSI KBPXM MAZXL YZEMA INXTG LSZKZ Hint 1 (in caesar cipher): ILUVW SUREDEOH ZRUG : WKH Hint 2 (in caesar cipher): VHFRQG SUREDEOH ZRUG: HQHPLHV Hint 3 (in caesar cipher): WKH VHFRQG PHVVDJH EHJLQV EB KRSH 9. The following six messages have been enciphered with the same key. Read the messages. No. 1 - PDGXU LNKGS NIXOK YJGSQ XMHSX No. 2 - TNEXK HSYLZ EXVZJ ERXNW HGLSX No. 3 - USIIM FXSHT AEPKV AXDSV XGHZX No. 4 - USBQV WKFIT TIVHW NVGAS KJCGE No. 5 - YKTDP QEKIE OVVHY NQHSY UDYCX No. 6 - BDYPK ZRNLI EXGOK YCJNS LMCWS Hint (in caesar cipher): WKH ODVW PHVVDJH EHJLQV ZLWK WR EH 10. The following two messages have been enciphered with the same key. The plaintext of these messages are (almost) the same. Read the messages. No. 1 - EJRLG NLROS RPJYT IIDBH No. 2 - SKCYU AXAYZ SOSIM XVTXH Hint 1 : (in caesar cipher): WKH ILUVW PHVVDJH EHJLQV EB QR Hint 2 : (in caesar cipher): SUREDEOH ZRUG : PDQ 11. The following two messages have been enciphered with the same key. Read the messages. No. 1 - DTMFJ JEIOG UQXFO DDJSA JOGOZ HPSBN QYVAQ TXXXX No. 2 - DTFFI QHDER LYXSP EXWLV TCTOT PPDVW LXQMV NXXXX Hint 1 (in caesar cipher): ILUVW SUREDEOH ZRUG : KRUVH Hint 2 (in caesar cipher): VHFRQG SUREDEOH ZRUG : JLIW Hint 3 (in caesar cipher): WKLUG SUREDEOH ZRUG : QHFHVVLWB Hint 4 (in caesar cipher): IRXUWK SUREDEOH ZRUG : LQYHQWLRQ