CP3404 Assignment 2 SP51, Singapore (2021) Due by Friday May 28, 2021 (no later than 9:00pm) Aim: This assignment is designed to help you improve your critical thinking and problem solving skills, as well as your information literacy skills (i.e. the ability to select and organise information and to communicate it effectively and ethically). Requirements, Method of Submission, and Marking Criteria: ˆ Answer all of the following questions in a single document. Each question should begin on a new page. ˆ Include your name on the first page. ˆ Include list of references for each question with proper in-text citations. ˆ For each of the first two (2) questions, write a report of approximately 750 words in the structure of a scientific paper (e.g., articles and/or conference papers). ˆ In your answer to question 3 (i.e., cryptanalysis), show all your work. Note that using the Internet for deciphering the cryptogram and/or learning the key from any other sources is an instance of plagiarism. You have to show (step-by-step) how did you achieve the plaintext and key. ˆ For marking criteria, see the included rubrics. ˆ Upload your solution to the Assignment Box, located in the subject’s site. 1. Combating Typo Squatting What can organizations do to fight back against typo squatting? Research the Internet to find out how companies are combating this growing problem. How can these typo squatting sites be taken down? What must a company do in order to stop these sites? And why has it been so difficult to do this? What proactive steps can a company take? Write a short report on your research. [4 marks] 2. Case Exercise – See You in Court1 ”Just before 8 a.m. on Feb. 1, 2001, C.I. Host, a Web-hosting company with 90,000 customers, was hit with a crippling denial-of-service attack. By the day after the outage, the CEO, Christopher Faulkner, reported that complains had come in from ’countless’ customers, so the Fort Worth, Texas-based company got its lawyers involved.” In a strange twist of fate, the company hit with this attack dragged not a hacker, but another company, an ISP, and five of its customers into court. The ISP claimed to be the victim not the perpetrator of the attacks and therefore not liable.The Suit was referred to a U.S. District Court, but never made it to trial. C.I. Host’s attorneys convinced a judge to issue a restraining order shutting down three of the ISP’s Web servers until the ISP could prove that the vulnerabilities had been rectified. The attacks lasted a few days; to resolve the issue, the lawsuit took over seven months, and several hundreds of thousands of dollars in legal fees, time, and effort. The question is, when information security fails, who’s to blame? Or in the court’s eyes, who’s liable? Even though the hacker is the culprit, with the standards of due care and due diligence, the companies 1Adapted from Whitman and Mattord’s book, which in turn adapted from S. Scalet’s article, CIO Magazine, November 1. 2001. 1 that are being hacked and then used in other attacks are becoming increasingly liable for damage to other companies. ”It’s not a ’sky is falling’ issue,” says one CIO when asked about likelihood of such lawsuits. ”This is what an intelligent, forward-thinking company is thinking about. We believe that we’ve taken every possible precaution, and we’re looking at every possible thing on the horizon.” The lawmakers are paying attention as well. A new bill is being drafted in the U.S. Senate that could exempt businesses from the Freedom of Information Act (FOIA), in order to protect businesses from being required to disclose the results of attacks and their information security protection strategies. Another bill in the House, would prohibit the use of voluntarily provided information from being used in a lawsuit in information security related cases. Although no direct liability lawsuits have been tried yet, it’s just a matter of time. What can companies do? ”The best defense for the impending legal hassle is a much-advised, often-ignored list of best practices. The question is whether the gathering clouds will have the proverbial silver lining and generate an incentive for companies to act on security best practices. In the process of doing so, they just might prevent hackers from doing damage in the first place.” ”There’s always going to be that rare group of people who want to take advantage of the system,” says Bette Walker, CIO of Energy and Chassis Systems for Delphi Automotive Systems in Flint, Michigan. ”Security can become a legal problem, I think of it first as preventing a problem from occurring. Then the next step, I don’t have to worry about.” (a) How can standards of due care and due diligence protect a company from being used in this type of situation? (b) Why would a company want to go after an ISP in a situation like this, wjhen clearly the ISP is a victim as much as the attacked organization? [4 marks] 3. Cryptanalysis of a Polyalphabetic Cipher: In this question you learn a classical polyalphabetic substitution cipher (known as Vigene´re cipher), and are required to cryptanalysis a given cryptogram. Cryptanalysis of an information system is the study of mathematical techniques for attempting to defeat information security services. A cryptographic system is said to be breakable if a third party (i.e., crypt- analyst), without prior knowledge of the key, can systematically recover plaintext from corresponding ciphertext within an appropriate time frame. Background Julius Caesar used a cipher which moved each letter of the alphabet to the letter three to the left in the predetermined order of the letters of the alphabet. Figure 1 shows original English alphabet and corresponding cryptogram alphabet in Caesar cipher: a b c d e f g h i j k l m n o p q r s t u v w x y z d e f g h i j k l m n o p q r s t u v w x y z a b c Figure 1: English alphabet letter and their corresponding cryptograms in the Caesar cipher In order to use mathematical notations, let convert letters of the alphabet to integers. The most natural conversion is to assign to each letter an integer which indicates the position of the letter in the alphabet. That is, assign 0, 1, · · · , 24, 25 to a, b, · · · , y, z, respectively. Using this conversion, Caesar cipher can be expressed as: C = Ek(M) = M + 3 (mod 26) 2 where ‘C’ is the cryptogram, ‘E’ is the encryption algorithm, ‘k’ is the key, ‘M’ is the message/plaintext (one may replace integer 3 by letter ‘d’). Caesar cipher is from the family of shift ciphers, in which the cryptogram is a shifted version of the original alphabet. Cryptanalysis of the Caesar (and all shift ciphers) is easy, because there are 26 possible keys/shift. Vigene´re Cipher In Vigene´re cipher the key is more than one letter. That is, Vigene´re cipher can be considered as a combination of n shift ciphers, where n is the key-length (i.e., the number of letters in the keyword). Let the message/plaintext be ‘individual character’ and the keyword is ‘host’. Vigene´re cipher encrypts the message as follows: Plaintext i n d i v i d u a l c h a r a c t e r Keyword h o s t h o s t h o s t h o s t h o s Cryptogram p b v b c w v n h z u a h f s v a s j That is, the first four letters of cryptogram computed as: ‘i’ + ‘h’ = 8 + 7 = 15 (mod 26) i.e., p ‘n’ + ‘o’ = 13 + 14 = 1 (mod 26) i.e., b ‘d’ + ‘s’ = 3 + 18 = 21 (mod 26) i.e., v ‘i’ + ‘t’ = 8 + 19 = 1 (mod 26) i.e., b Since the plaintext is longer than the keyword, keyword is repeated till all letters of the plaintext are encrypted. As it can be seen, a particular letter of the plaintext may be encrypted with different letters from the keyword. For example, the first occurrence of letter ‘i’ from the plaintext is encrypted with ‘h’, where its second and third occurrences are encrypted with letters ‘t’, and ‘o’ respectively. That is, Vigene´re cipher is a polyalphabetic substitution cipher. To break a polyalphabetic substitution cipher, the cryptanalyst must first determine the key-length of the cipher. This can be done using Kassiski method. The Kassiski method uses repetitions of patterns in the ciphertext in order to get a good guess about the keylength. For example, suppose the plaintext ‘to be or not to be’ has been enciphered using the key ‘now’, producing the ciphertext below: Plaintext t o b e o r n o t t o b e Keyword n o w n o w n o w n o w n Cryptogram g c x r c n a c p g c x r In this cryptogram (i.e., g c x r c n a c p g c x r) a repeated pattern is g c x r, where the distance between these repetitions (i.e., the number of characters from the first letter of the pattern in its first occurrence to the first letter of its second occurrence) is 9. This could be the sign in which the same letters from plaintext is encrypted with the same letters from the keyword. Since in Vigene´re cipher the keyword is repeated, the key-length is probably 9 or a divisor of 9 (i.e., 3, because 9 has no other divisor). Assuming that the key length is 3, we split the cryptogram into three cryptogram. That is, the 1st, 4th, 7th, ... characters of the cryptogram are the result of encrypting the 1st, 4th, 7th, ... characters of the plaintext with the first letter of the keyword (in other word, they are shifted with the same number, as in the Caesar cipher). Similarly, the 2nd, 5th, 8th, ... characters are the result of encrypting the corre- sponding letters in the plainteext with the second letter of the key. and the same for the third file. That is, this Vigene´re cipher is a combination of 3 Caesar ciphers, where the cryptogram of each Caesar cipher is given as below: Cryptogram 1: g r a g r Cryptogram 2: c c c c Cryptogram 3: x n p r In order to break each of these Caesar ciphers, we use the letter frequency in the English text. As it is 3 Figure 2: Letter frequency in English texts shown in Figure 2, ’e’ is the most common letter in English texts. That is: In Cryptogram 1, we can guess that either ’g’ or ’r’ could be the corresponding letter to ’e’ in the plaintext. If ’g’ corresponds to ’e’, then the first letter of the key should be ′g′ −′ e′ = 6 − 4 = 2, which is ’c’. If ’r’ corresponds to ’e’, then the first letter of the key should be ′r′ −′ e′ = 17 − 4 = 13, which is ’n’. In Cryptogram 2, we can guess that ’c’ is the corresponding letter to ’e’ in the plaintext. If ’g’ corresponds to ’e’, then the first letter of the key should be ′c′ −′ e′ = 2 − 4 = −2 = 24 (calculation mod 26), which is ’y’. In Cryptogram 3, each character is appeared only once, and thus letter frequency does not work. Remark: This example is just to show the mechanism of the Kassiscy attack. This attack is very effective for large cryptograms (e.g., in the size of cryptograms given in this assignment). Your Task: In the following you can find 10 cryptograms, that are created by Vigene´re cipher, where the plaintext is English text and the keyword is a meaningful English word. You are required to decipher the cryptogram that matches with your Student-ID. [12 marks] 4 Cryptogram for whom their Student-ID is XXXXXXX0 oifwkigabwggzeuilnfvqoinxpvcuckxrzlldwkmuyfaamirrpwflglaoikpfzrpvytzvr amjlwxlpvytqflazsvhngapvkonguoehbvwmzgfosyussgrjmvvkbbtchkgimfdhpsgrnp pblxbjgnvsmiicjifnglystqusugzbagulgzpwwtimtifhfzepvsehyczqygsiahvfhhuc uglasfppoagocqpofthlplbzbgzqdpqmvvqpofthlplqkngvbawltyvromjxggmuaauwcg aggyhyczqygsidvzkbueckuwlgrelaggsfdapwzfvyamkmotfpmnxavlaagyafblzfvfpn awykogffqkmvvbpoamocqpofthlpllazwkysaazbrrbzwlgymbtvuszlhawggvqpuaeoir vpsgrnppblxbjgnvsmiiczaagqvyjwhrcwcsmumfflpkvhqlklvllwjgkmfmwtysbgmvvm yqybbrjkqybhrjzqygoksymkaomcawuksrrlagfsjmybgyrzepbseseahxknzrrpwfycir omvhqlklvllcrlfqfmsidlzwgqvupbzxwkflzamgtmubwghjmybzxgzeuilnfvuptdusuc amumsuupbztjvpfpazvgpvjsuwcgagagciblzlhotfpmnxhygzzwjizpluwghrbpoamocq pofthlplwftavqziyxwjyzxwvwrjlvukmgrpwfhtkfluwlgrelbzthtyujwtdgjpmvhbcw iglasccnqlbarrlaazbvpapsmwjgukgghiyzblhvrlkejbhkcuaazbrrbzwlkygjpskszl kmhxbucubxkcdromexgjynmkmvvbpoamocqpofthlplaengkqvuwacnzpvvmckfluwlgre lwxvclpzmagpfropsgrnppblxbrlklazwkysaazbrrbzwlqyctmkmvvplkwbjvpvnlasjg nvsmiictckmpvyitwmcmcyqxrhyczqygoksymsaoebdzamhvlzqygoksymaljvppnaxrsw jweioiguoamhfmapwkolromfmwtqpofthlplaxhfvvhuheszlvzvxfkmdqlariyduggspd ywetprlrbzxprlrkgfdrplalasjgnvsmiicdqlacecdpavvzqwzgowuckiltqtmbvlhdvl pvymwdchdwkwwgjilbcemmivbuzrhtkbueyacjxvfuldwkbvckalhognsgsioirpkmeoig uowgsiysihnpcgjtqdbfuuidzcigapelcrbpoamocqpofthlplauasdcpasvccjlklbcem mbohocevzamvdqhvvfijroinxhycmwdecnguohkcgcybaxgkflaazbzlnidzcigapetgjg nvktgzeuilnfvmmbzxgzeumjyffkapwlskmmidedfqzqtesmyscwlcwromkbueyacjxgkf laazbzlnidzcigapexlvabbwlwenvtqgcdghtlbavdvzsgcgnvvwghnfvlgxgemasfhkkf lawvfvrrmqbhjfvcdwpvavuhnhrrpwftzcwpvlkotrhjdxhfdvzyxojgnvsmiicapsmwjr vnagrrthtawgzeuilnfvdvzszwmcuuwlgrelbzxjvppnavokgvvseufppbzfhrilasiisj pkagtfptilbcemmbzxgzeumjtavqziyxoebhoaoseqpofthlplwxmvvklaktuvgazwmiil zgwlwwromkbueyacjxwjelvmbbvmapwkkzqlqlksksyvkgckfldwkwwgjilbceysogkwkf tqfzsecyidbgrnbjdbqcwrvgpbgmsgfhazysbafsrjnwjbhykzwsgmfllksgijcpblhqyc jsoaskflzsfsjqhowfokaomkmvvqpofthlplwjgck 5 Cryptogram for whom their Student-ID is XXXXXXX1 omqisespiakgwfvoangvkuvqdiqimfsrtklowuiakgwfvzprpzljmekzbnbusyqmprgkjo ljweagvqhymeuhgkxggnbruucahtwxzrggwtlvbxbubusjmiwaryqmprgkjoliwtsxmlol kzqbbjixmccgcriewekxgchfoxicvplamgckpkqegzuvtrqfuvcgokquvnzimwcvfvukvg gditgfqymsmfvrdkjrsexxwccjmjnbftwtlhqkqtofstcxmiwtsxmlolkzqbbjitmaucqy pnitbowawjilqegkxxqpsfxkvowuiakgwfvzprpzlgubiebyiesbvueahfirtcoibomfoe lhqqrvzyighvuvbgcfczjvrviipbhymxbusyqmprgkjolqsinuznuzdkvgwdmucgdvzowq kzvyiardcybcopitizclvzmdirtzwgvveovaweohqqoemtoywjpgcphzwtqfhymswfhnmr txbfetbldvwlihqkquvnbuqyevrvtecfsunuzesrtkagokmnwjsmmxqgzvayiqogbgjysk wuvywemyqgirbowagtwsxnfvlzwfsrtklowuiakgwfvylhskwobffvtoiaqvwtzrocbour diqimhduizmfseorqfvrvjdvqbzkgnitbowagrzkkbbjqjmesuiyifqvvjqauuckbbhymh qqrvzyjvruqtohdkpkarhktkurbkxxqps 6 Cryptogram for whom their Student-ID is XXXXXXX2 fhwvseoehmswyudmmcqvwesitiwkeiohaveceeukikehskmeswslgfzsawiiqdtrwvhejt prgtzhvjeewysiqxsftcqsztqzdkgmlrdiamsrzduaeizekllryijlyxsekmwktalmliqs zhpueczxqvefgklzqrskgyucsekiauhlgrzbwkirxirxhskgaomesmgkijtajxwkahazlv dlwoicbajmmtupsgxjwolaeiucggwzpejxhyuejtvttiutpktrwllfxdkvlvyekbrntiua ejumheikunamliqszhpueczxqvusslwfoismiuiilaxyqilapvhedhjryudmmcqvwekiau hmlvabnbsledjtasmcchjktiklscgtahrzetztxzfdgxweathksmudwvseoujkieoysfse sdayjvdefmpvhedlswtiwkeiohavecsrgntjutgwmjoukliueeukikehskmesfgkkvzejt procwlwjfrmvxldektrubrgoiufhsmimqrqtgtqsklxigclnvvoafuiiqadbdvpbqttvdf wvxjqcjxxjtajbrxeczxqvfhwfezzdjtasmcchjkteakwtteexmjfhsmxyqmgkigdinbpv sevieifiubtrztktvvmskbkeqddhrxqrkaeiqskbqdankiszztwwslftztxktekhplfigg wwarkxgiqtkaeiunybrdgllbpvhedzvfgpkivfbokxhskeskpzqrsnxyarktvvzolxjwuc axrkteknkxqslxhvrfavmvztyxsdqtjbgrxswvvvfsztvzzgkvlvyekpmkttzxvvcuakiu brgiiifiwllfienxvyuskhplfiggmjmphemtmbdxsexylhegmrlbglxajvejqoxfycfidx zvxgjhygemgkigdeubwvxyzxhzecmlwvpswvvvfsztvzzgagqlxtaeimqlykslbsobxyba jmmtglsketoeklwkduumyiqstkmtwedewkgdaxhxqnwkeceeukikehskmesiffycfidxzv xgjhygeafwtiavwwxymtammjboklmsxelhgfzslkytfivxeceeukikehskmessuaidqsxh vrzyenpkulwoicmcuxwjetjngkgrwbrsdiudicxsnxgkarkietqcggwkduummfztzxpfie juslzdggxyqsasifrtzxqfpudnwgeirxswfhwymvxdagayuczmlvoadvycmtahrjmrwuiz zgvhrvusuhrjudwkesxydtvxqifmlzeswvxzanoxtiqswgxrzexymtuefmwfxulbserojl itdelllrdifzmeyudmmcqvwekiauhlsldsuaidqikuejqdggxyqsztqzdsuaidqafwmjbe jyitfafwmuqadbrfgrkvlvyelaicawwkffgnvhrkteehhlxukbwjugfbjzoafmppemsepv dtztrzzbjbgbqldlwtteexmepewwxyqcgghzfiggtzegjxekqrlaeezakbrjtaebvjaraz memlkvlvyealwlrfavmvztlhmdblwfiefomktiapgliueczxqv 7 Cryptogram for whom their Student-ID is XXXXXXX3 cgqprcccgfwewmhhtreexwfkqcklggbprkepgqhtrfnweweuxjsrxrjxumeiedshauaike tmogygxqudppycefketfktobwyzrkhetaipamqprjvggqbbcifjqgydyevetciivkdxtzr ihttwvpnyzdwegcseprtmrvqgwymevipslwgrfdeegtmbimzpkhmgyfvfsdhijepsjpmgp gcrihzwisztrrxkczxnklkgenskioqtprrgvsdhwvvghdpnjjqfytdlwkbspvvvagubpci uinhtzxwhudnzxyoegerwqbmqlvxqoehudivvmityiefketfktoylajwvfacgvrqiswajq qgfdfklgdaieexkoxptkeeyqgsnitsualzxgfmierrfvaeewynzkdtyitgiduchvvuckkl chfweuseiytnkacgigikxgbucaeypyzdwejqfqxgepcbsjaxikhipshykqwayiiczuoeux jofihveuggbpkmqbauaemibagaexchfpcbitkmhnfxtsmaijxkqydskicfxnelvqdqpntv adfdspwvsyhwvvgrqhixrgrfdwzxjgfpnuxjsmitrgmgaueuyeoftdftrcztnkwyvaznva vvqtntvadfxoettcotsjfwhpxdesvyzdwklgqdnpksifmehzgmskpdumvwacacpawflajv gegtskifhtptklgszrrptvwacaehfsogygxkczerfgggetstswzpqeuspscjitonmghurp nmnnhrrfcdliklvvqpiushaqrhrrkqmadvzkqqhslgjoeihvgkdttrumuyucvvrvspqyci qbnptkmuomabvvvwmityidssxnempuautyipwzttviphtreexwfkihvjkfeimvgjozxcrp gzqrtimeoxbatlkbqhwvvgwzirfhwqqsffvhoeieegtmbiifrvvuhwrwvvquiiwvpdtabx jfajgympqdnpksifmehpwjozcoempvuhsvqkbmawfvmzmxdklghttoiivwoplwswbpptzs pgaumfhgfzrrptvcsgaglavqjsvhkbrdrdevwactyiqfkiorrczkhetmrvqgsrrfqacszh gfqstyiucoplcifddddlgvquehvvuktxcyyusebacpuinhtzxwhudnsszseroergqftdsc nodveitgfyjtrxkczqooiuggqskmvifxoefqlqhacwqqmalvhupamejetsodnkvqzxtdsc cfqaakmxsxnsysthogygxqudppymeyqntfttchxdvgqbrjszsphttpvvoifptzsppamejl qkqkeilcjqcobiahttiiwvfgrtlvgweuioifozstyiadddvzhgruuflwkczerfhwqfrigl gfeprvengaieiqgreenvxycdzsnmvvajtvbesbiifruoxacicrhavrrtjwoplxstwfwmje tsnpsvhqbodmgyvofxoewkbrxnzxgoxvesvcwohtiyehggejiiuddugwtwzvswmgzphaeh xsoioiwrootsklgfqhucxucrihvwgqabplxchudnjetsmawrcusjpckrqfajnumpuagagt tcjxmrxkczxszrxcxkeusphttcfrvfmgyrwkbsaesmvsdgoimphttietwhauaecefketfk tobwitenuagiklouqceievsepnlrkbftnkmqbmarvwwzfleuiuqdxbvhcbqlaehgtrxczi phmagfvkhtbffvvvqbucxkdxxcrxkczdfwpqofxnxtqwzinlqdsdhwvwwustskifhidsvg wfqesvyfcdpnusopuigvrgfmioiwdoetdfrvfmcstiprqctrppiyqeiwvvqhekaqqxpsji ucrirrruqqcdvrvoxhaiicdbaivhvcodnjxtioinfzgzqccicrhudnrpicdxtyqu 8 Cryptogram for whom their Student-ID is XXXXXXX4 iyselxmteqsjtfxfbteezsrfeheeiysgtveitcnxidrzomrvmsvapoidctfzaxavioqsmo pcupcmfwdkjelaevbmjezswimwceevqjqmqszaqwiytehbemacusulmxhzhxlwptmsmztq swfpxpgrztfcezsmssjwadepfneytrgulrppirgzvqctfzaxudewomezzzbhlrpdkvfcra cdwmtxmgpoqapurrhjzrexkitpwfwvgbxirtzguppeiiideydtnwuswtdihfchmirpmzgw hrbelwtdihfcoqnrgbxefivfpqjmrkhipoqntcoeeucjtjqxkhzljyhqevbeprfperftkt igostxkrysdvfuijrvpxaxkgxthqjkwmtwmizcoelqsvgxlwqmksodmhtcmjyzqhkwhlxq srbelrmapgfoxttvlqpvuteqfhmfwkvflrmapgjdsriysepwspmswlpgpszftrexxvudmz ifhiphqhzuoavaevfutiedwqsjtfdxfbalurrzhzvuiyatlqacxguelqbrbzoiervbelrf hftusiptjkizwqhkfvnxggvkbdfmhvrpyjqxjhfwtqgdiulxudeospxttaoqlrqhvtbdxq ctfzaxudeomrsdxkvnlrpiysbfwfgrzjlrxdbwbwkagzhixraivhilxmachipendmsnprf xfbfogdnghprvmeywddceivatlvqeiwwlxqzvmtjwftdgjytdxmoupoqntfzaxahpgupqe qfhielqteqsjtfxfbbyhfwvrfnvkekwpyoqnjospwqrisulrptzhipvfwvgbxiagkvfvra lcseriaufbfzjfwvajdwguwwdtizikcepxqgdwopxttfhipvfwzgjdatngfjgeftbszdce ivatlvqpcgpnexavrtjqytkfjnwkhksndhuuwwflrpwvzmxezxehszhgrvrusiodeqfaxa ugicwmozvmdccbifgzdxqbjdvmpurbsznvkekctjwftdgbwwarrzmphmhpanpxdxtgzdxq bjitpxiduwgqidtehlpcedesjdtgqcwdhluavhipsfwvfjdoqekgfnvqitzflvxnzhjdvq flwsphfwrhdzqbjkworxttjsdcifzvmgcsyiysqffxxtcoplmhkccpmziiodeenavhiciq svgjrreqrgfosziysozxudecgaynazqlpcenjhfxwitisqffxxjvfovukvgudlmbzfbyhm scsnlrewfkfolalkvfqeoiffjdefxfbqcsnavadzyxsssvdipifqpywfglqultgqcwdvik rimqesenjhfxxtxjwtelqlvzmvraleftlgdnghpdceivanpvwavooolqacabyyetuhipoz pggbnobgfpmpquckvftvodegucyoizcoxgqazsdpfgxchbdceivaxsmowrdqwmqsvfszvo diffnxucxqpoiearhfcmztcubxexrzhfppspusttkztuoqffxxtyfjgdnghpdceivavdmz vkvfomerisuppavrfjelyeiccwiybzzmpvmcuypmpuiqgvrkqhksefwucxsmwmbizqdfvh tjhpoiexxbqffxxtyfjgdnghpdceivat 9 Cryptogram for whom their Student-ID is XXXXXXX5 pchhlptizjhfatcrifnkhctoqvgxbusvwggszbjchmwvghnvetdsqnrkxtslmdbsuczhtt iysunjtcldlhcwjkqkitktmsumgtjthlipmwvghfnxgxfdxwtacmoiyxgjvlmjxgftiytn ckwoudnnvfdwexekgdoemxfbvihmwzgwsrxpiszcfxapivyfbcdouegmhnwwbrxgzgkude ttcpgqwxkwhmunryovmgtufcgxwmryoxwvbdegkuxxiysquvngrzslqitihbihvdeqhunb cxhkynhhzbjvkwhrzouwvizcqmfbhtivmgwhftdljtkvphyplxeuoykgiysvypltkvdnva tislmqgapcqyuxacsucptrfbwcpndlggiwuavoxwvbdeqguvatisdlgfpemeoaxgjoqxux acsumyadtcqnkgjfivfamgrrhuubcxzhwqfbfrlnauxugdlgfpkqkyftcuqoycktucyytm xdsdwehguwqavhiysdoemxfbuonxhtrdmcktkmscetacmrjggqzrwbgutjhnhqpcvldgre tftdwftxjovyengzhlyufpiyhnunryovnjxcvkbitdhkcfegqryoqaggnjswbgkteczyzb hkbxggkdlgrhnbcvpuimxgjwwyuljtvdmehbdghwvapkcizgkhvfycexhwcunttszbjcpl ttiucvbtjadlmxijcqfkgtsfregkhvlkcdbikvhmcftwzdquthdcuyehcmsqnkhcrzrhnb cvoxwvbdegdhfhuwsuhqydiarzrkdksfnkhckcecfwtigfixxgruhihlttiucvrxjgxyuy diqguubhcwpcvxsnoqacgscsxhiigfdrmgwpjqkyoxufffipwjthlhilttiuycgsrbrhaf dlgfxclwfkhpgkiywvmeatdslmkghvqxlgtcurryugdkogxtxhjhkyuxrlflnkxhdouegm pjdhwvhutrdmyxlzzoxklrlgvnjbhzbvyemxfb 10 Cryptogram for whom their Student-ID is XXXXXXX6 eflrxdztocjcwtuehkxttpskviclkjrxsrtdiycvnfqfresbinskvigfukvnpqxkbgtssn esqivpwwoynciatchildnvhukwiaggvuxwxtsvuldpgjrterhnzrexxhpcsdehbehrtqhm jogcvtwkgpwwhxfpekiueabbyeetthlkwhhosbpidkuczgxwbpujjmrausafwgxesvxihh tanpmennoggwxghceoeibqbgjihxprrtmhmjsccvirkbnesbfwbveeibqbfawixohucxxl vvrnivbvwzcxtmtoauqxmvseqjxghceoeibqbgjigxesvxigbuhugtpkvmvperhoahpmrt vwbpwnlvszvlpmkggjixgvsafiskgqvrmtgvcskruhtanvmdgcbnfztkuoeamhtroevcxg cqboqjgkqnvmdgumfvibmjogkwcxkhugviaggrphtkpcetirxkjrtecwyvvelikksfvssx hsnvxwxkbsqvbtvwbpwtvwfvvchxtjveiqxkbtrvdokrrfftmysrpxwxusafigtpreggtb xseuirkgqlgrhntsfvlpmkbsqvbtvwbpjahyprvatxphugwtgfsecrsmjseggtbxsekwjg kbggpabiwoniihqigumsxtgvvtghvspvwxghceoeibqbniexguhgjvttvgocwtwqbrcztl ffbrtxgiwavivkkhlgrpunsfvltkgqrkztkvcigvxyakugxwxthugqtluotglpldsrpxpf rseghlbvvoasjmuwqgvhpjwyuxxgvfnpwxmxwncrjguspwvtwevnprtekhrpwjkgggjeit pmzqhxykqnvmdgqtgjihmtsnosufggfcktlywynftwghrextwcbvficmktveeibqbbttpk vmnwxwxphveeibqbnuwjkgggjietthvgwdyvvrkvxwgbgkxnfggfckttwhugribeogksci tcikhtlvcgjietthlylxvjfreixoggnoihlcurgzxwgbpgsumjsvficmkhlqjiaggrphtk cqucrcxnwfcqttpgbhgdgxslkrvbptbtqpmkcahvdfqbrregmahbcrdmjsecwtvwfrelpg psyqvpitwicxtvjoapiabucagjghokukgwtpoqxiglcflfstlpcgjekxvvrcfxekhlvsgx qfqgvsxnsggmclgfgqvgxcrnpyclgqhtisvjoapiahtocwfabequcrcxnwfqrtytczylxv jdntxxxucgjigmjoavldlgtbtawbevgjixghceoeibqbvumcmgbqghrtpfrqvsxtrrniix kbfgvihtfrchtgeflrxxhpwfvltitwzkxxogqeatihifnrlxvqdrteibqbhuismqsauygx usptirrqfpqrubfsavmpekhlqjxghceoeibqbgteclowgvistefbuwpgwbfggjkgrpqqbn pwpcxxhpqucrcxnhugicvtmcvmdgqdrteibqbgcotlcdvggthhwahsgfchvqrpeucpcpax faruwpzgcerppbphrzxpgfhecrhyqfzumibphbcggrrhbivpfqfpktwxthrzxjlkbtcwtv tsgevnivctteeakqxgcsxeflrxxhpwfvltkgjrtwthrsecxxhphbgrrkadgkscmjseggtb xseyldaqzquxwxecetirmusptiidgmpcrgxecigviagaruwpzgdycmcmglghvdfvvrevni vcttebvkdugvixzh 11 Cryptogram for whom their Student-ID is XXXXXXX7 yhmphtvdpbtieeqgwccklrozoytvdpbtieeqgwccklriaebvtwokpxlvjtplnuixcztvvw yhmdnvtgyaeyghjskccgxnovzzkljevnlptyiwyiihjczjjkmtnxcitixsqqnyiweqdhfr jeleiumxtqyalmxhmywicutqzhwvtmlpwicutqzhnihatwnyircwwfvgyidpfpgnpppljs wczjjksxyaeydwurqgukipeglfjshatwyuwdmupnimhczjjksxyaeydwzsmebvwfmmdytv jtspswswevnlptyiwyuehiekcsgxnovlfkltuosnyijnkcsgxnovlhuhjczjjkmtnspsjh tnwehviitwmyzhjnbtwrpyhmvhfaqelryfjtnmzzkljmafzwmheaeiffyaqynyittpplgy glqnevcflazwrpqellmpqrebcctgwyxeijcxtmxmlwjaltzwiweveevckozphtvdpbtiee sdlpwicutqzhkljkvzqciigmzzfrjkmjbfajvmcxfixnweucptwbsyfxmezeisiiebpldm sellieibagqoegyiwycjekuvnnzssfwcqymhhqecjifsgeitsrpceyzxxviwovjwoutnje wgcxyexxbceckmxdqqzzgzlbeiiiaezdyzxyhiecjxtfqyxzxxazrodistavhfannotnjz flcpwicutiyuccxiatmkljsbfxpskmiebvqftqnucxjcpychyjsnzlrxyeuanzrltwoywi ftqyzfvrabtiewjcccckcxezgctixakcsgxtsgdnvqtrinlptyoocuglncajmkirialavr jriwnvvrrmqyivnnoeirwjtwqwicutwrlrtmikalzqntqgyjyxeleigvtvqoyzrkozxukm tnapwlvntgdyizncmdgfwyoneyexmiaeyiqnscdyumscwydlrhtqzhnmyhxccdmyidpmgv tvqocekhovqcuistqlfzxdtplnzwjnkcsgxnovlhvrhrganzsssgdnvqnsalcuxtbmmlve pajwyzjftptlutfrbjqzxmocejimtrsyinpjdopiwxmespstessgdnvqftqnucpdrmnimi wptlcexjxbqlfqhozcyjttnlthxgnppplkictetnymsswxyrturwalzeyebtgvjwaupnyi tbrpwkmaewqnyikotwinmsgienrgpsqdnfwdsbpgrxnciwfpvjcwgyitqaqynvbyfzzgtm uhmcnvbyozppvrrozpxiextqnucpdtwoyuyhebsyuihrganzsskmjutmuhmcnvbyovwsrx yakvcjsseesykljrbsyrhaezduictrkcsgxfniwsjxyrqpmksielfwvxmelpwicutqzhbi dozafrmstminsctbaplmmsgktjyiwtminfrqyiysvrhrganzsssksydiautyyieglmeikl nsbjjvskabeutonskzhjmiezpxksgekzggpjtmwszrxekflvepnwhhgpfiveyoxftblwbm xovpqyiwebsyrhaezduicmaalklestqesfjulithkictiyxtswrmdjfriivrwztmezeyox fcpzmvrulithkictienrgpiazhvamezpnyifddpljewyksifwjsxwuzryefeuehnsbsyek nvmywfvweaaiehnnoncgljrbprkwzbapklisttjnyifddpljewycdyjxmeqyzfvrabtieh jdcnyumsozoyixtrmnimiwptlcexjxbniivjsxzhumsgbzjiiaiwfmccznapyegnppplki ctwcnfjnnlebvojyiajcmjdinbfwjnktjyiwtminrxyakvcjsseesyiiyhmlxmiwsicsji qekemkljcqabvvyefeuehnsbsyeknvmynyihozcyjttnlthxtqaqynvbytppisnjcbtpvm xtpphksgeimfvxtdmootiyhmafrmstminwvtmltzwiwevewztmezeyox 12 Cryptogram for whom their Student-ID is XXXXXXX8 vauxgjkzvvhtramgrmcxpvxjbqjwnbgfhychwumwdnjzvtbkamqvxfzmibqtgjcnacvfpn owikogfdkurgkchqumvvqzkwkwkwjnvasjwnbgfhycmmcksugangkserrialweucqeaotp txvhgpqomofopzzagviicvuqgukfzuyxqflnqfxfkfznqezfudvifcucgahhfvtvtwthzl bbjxgvapzkmmfdvktrdkmngumsdsikqgrzrdwptzjcxctbhpyxzaihfqtavxazqnikwhfz zcpvcebdbkhbrjgguxqlpzqhtbrbqmtloiwcixbbxsitkfwkcykqfdlrvbkhbrjmmuhiia zaetbemolgysrropglmjrzuwgqflyqvbceygagviigoghhfrlzvekmgrdwplmjrzuklqrj gmfisidzkvlstpzkaycinzzhxqkqzktxqpmwagkjrrdwphtkfzkkivvpomzmdimqqfxgem dvhhfdyoqqgkyyoaqxjvpowcgoutzzutfpyimexgjymgehbugoqqgtfpvaafavrmqedspc iktrdkgjvurgkchbqusllxwpwwkgjvcezpqzkwkszqopcmhycfmausrrgmclhrqgwpzojr cmoxgjybmvasflzbkfsgyyqutbvvvuresfdvvwgqflyqvbceygtalstsmmggqiwkbkhbrj bwtbhykkcdewtizgggqiwkbkhbjacmoxgymrmxxftyivqmpvsikqgrzrdwptzcwnmenfva jurnhrrdwptzjcxctbhprcqufsrqpzglhycvuqnbkmakqfdlrvbkhbrjznhhfkpzywbfvb wgvasscnbenficibnryemrvoxhymyavhrvdzivtgpqomotdimkwuxrrjbwtbhykdautwur jjgvcdnpbcmwflvtnrgvapzgbtkfzxgkqvgqmfesmcgwhvcdnpbcmwflmmsnwicybqwswc vbkmsoazmflhycxwoiikyoqqgocpzaqnftcnwhmvvftxqmvvqdagwoutzzutfpkjavhtkf zjglhbljepvfpnowurgkchakgqlpmmpmijcvzgvcdnpbcmwflvtnrgvapzgmvvkzudxfjm abjbgtjvautfvqjugmwdcninlctygtgwdiyxbkvocjtagviickzqoosjzagviigogcvfpn owurgkchqulozbowdxdimqidemjcxctxwwrcmfbtwgxcnmmfdymhxokgiokmqrlwmuacnl owdxsjqzvvbocjtiuwwwddkwehrqnwnoweevegezbljepwwwddkwehgpjjnxajsxpclwer zogktraowtbgrrdwphfkfzkqfdlrvbkhbfdyquvfvrztqzoigopoldimqidesjcxctbhpg nkqggzbzzgwhfzzifxelyomhhfdmnbrkotrdkceogngqethzmiaehagsoivbceygagviig ogkgqcsymuifftvjnxgvapzkmmrqvxthdvpncdlsk 13 Cryptogram for whom their Student-ID is XXXXXXX9 buebrrmlqdkrhyirlaxalsjciyspccfzgiipxuxqfkflvqzyevrzzlxhyqkghuwwkclvjt vplvpikghuwglaahwzvebzpokghumbtcgamjvqvyirzrvhvriczpwhiympsbvqvyskjckc mqvqtuhweqnyebtcypvgkjrsekjatufsdywlawkfklkoibmvffvydprukfxyyzvqyvvsoy fwpsucyhyzkggnsbgyrtibkmkprgzbxyxfrbbukqfsekvsjseambrdbuioebhynozjllrh vlvlebfralvgfjnamceglasdimophsrlbugserbcigtfxtihfpxdefunxvtzvrahxtfjev ahyckbpsjdhyilrkisissyrvjtvplhjsvbuhgyjwlaiakftaezcmpzfipckzebuqxspsiq mvgfvymltffdbsigrzhbxsraavxvvpuhwsumgwvsmghbwrvyeprujygfsbvatuzwvumoig vnkvjwccliitfpxlrurebukweznzmbvqldmhyralmbugophirjtiymvphywscjxyawkftz louwkltikympsbtyghpgfzxipotiepwhvbyysawsmbvsrsvamcenkvgsvbbukgzltkhwkg hugfvbbagoibklkwjrkhxwflvhrpvsllhojnkvstfdbkibkgmfebuqxjyfzrrmsfgyrtib kgghwwdgehvarlglvsjakvagvpopgsjpxxywictsppzbwlvgkmiseqvralmfgyrtibkggl wqimpdlwtfbziwkfxyvswsgkirfpwltcjgmlhrvnxuhweehuxvvynjxwflhbxqfkxhphvp ghxscwbuwiiygjiqrlulstwcklhhfntyxwtgihrhjggzmhlympsbjualvskfxfwiwdxypc jqtzefvqnsxcwsgmewizxoejzmny 14 Rubric for Questions 1 and 2 Criteria Exemplary (9, 10) Good (7, 8) Satisfactory (5, 6) Limited (2, 3, 4) Very Limited (0, 1) Title 10% - Informative and summative in an excellent way - Contains most keywords - Intriguing and thought- provoking in an excellent way Exhibits aspects of exemplary (left) and satisfactory (right) - Too long or too short - Partially informative or summative - Partially intriguing and thought-provoking Exhibits aspects of satisfactory (left) and very limited (right) - Too long or too short - Hardly informative or summative - Contains no keyword - Hardly intriguing and thought- provoking Structure 20% - Highly appropriate structure and professional format, according to the genre/text type and task requirements, including clear attention to word length limit, and effective use of sections, paragraphs and/or links - Largely appropriate structure and format, according to the genre/text type and task requirements, including attention to word length limit, and use of sections, paragraphs and/or links - Inappropriate structure and format, according to the genre/text type and task requirements, with no/limited attention to word length limit, and use of sections, paragraphs and/or links Content 40% - Identifies, explains and prioritises key issues in a complex IT related situations, drawing upon relevant theory and real or hypothetical examples. - Demonstrates clear mastery of the material in the topic area, and shows excellent ability to synthesise and abstract knowledge - Identifies and explains key issues in a routine IT related situations. - Demonstrates moderate mastery of the material in the topic area, and shows moderate ability to synthesise and abstract knowledge - Demonstrates little mastery of the material in the topic area, and shows no ability to synthesise and abstract knowledge Readability 20% - Excellent progression of topics - A highly conventional academic writing style, including the use of appropriate terminology and unbiased language - Satisfactory progression of topics - A largely conventional academic writing style, including the use of appropriate terminology and unbiased language - Unsatisfactory progression of topics - Unclear explanation for all concepts Referencing 10% - Adheres to IEEE/APA/Harvard referencing conventions in in-text citation, presentation of tables/figures and reference list, with next-to- no errors - Mostly adheres to IEEE/APA/Harvard referencing conventions in in-text citation, presentation of tables/figures and reference list, with some errors - No referencing or very limited use of references Rubric for Question 3: • 1 mark for determination of at least two patterns of length no less than 3 characters. • 1 mark for determination of the distances between the appearances of the patterns founded in the previous step (highlight the patters in the text/cryptogram). • 2 mark for obtaining the key-length, i.e., the greatest common divisor of all the distances you computed in the previous step. • 2 marks for separation of the cryptogram into ‘k’ cryptograms, where ‘k’ is the key- length computed in the previous step. • 4 marks for the determination of the keyword, with proper justification for each letter of the keyword (i.e., applying letter frequency). • 2 marks for deciphering the cryptogram and obtaining the correct and readable plaintext. Not that determination of the keyword/plaintext from incorrect results in previous steps is not acceptable.





















































































































































































































































































































































































































































































































































































学霸联盟