程序代写案例-CP3404-Assignment 2

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CP3404 Assignment 2
SP53, Singapore (2021)
Due by January 23rd, 2022 (no later than 9:00pm)

Aim: This assignment is designed to he
lp 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:
Answer questions 1, and 3, and one of 2a or 2b in a single document. Each question should begin on a new
page.
Include your name on the first page.
Include list of references for each question with proper in-text citations.
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).
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.
For marking criteria, see the included rubrics.
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]
2a. 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

1 Adapted from Whitman and Mattord’s book, which in turn adapted from S. Scalet’s article, CIO Magazine, November 1. 2001.
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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
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, when clearly the ISP is a victim
as much as the attacked organization?
Choose: 2a OR 2b
2b. Law challenges
Read article “Continuity and change in internet law”, by James Grimmelmann, in Communications of the
ACM. May 2019, Vol. 62 Issue 5, p24-26 as an inspiration about how new applications and uses of the
Internet challenge the sufficiency of existing laws and regulations, and using additional references for
further information, write a short report on your findings of these challenges and the solutions that have
been implemented or suggested.
[4 marks]
3. Cryptanalysis of a Polyalphabetic Cipher:
In this question you learn a classical polyalphabetic substitution cipher (known as Vigenère 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.,
cryptanalyst), without prior knowledge of the key, can systematically recover plaintext from corresponding
ciphertext within an appropriate time frame.

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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)
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.
Vigenère Cipher
In Vigenère cipher the key is more than one letter. That is, Vigenère 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’. Vigenère 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, Vigenère 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
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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 Vigenère 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 corresponding letters in the plaintext with the
second letter of the key. and the same for the third file. That is, this Vigenère 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

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 0g0 −0 e0 = 6 − 4 = 2, which is ’c’.
If ’r’ corresponds to ’e’, then the first letter of the key should be 0r0 −0 e0 = 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 0c0 −0 e0 = 2 − 4 = −2 = 24 (calculation mod
26), which is ’y’.
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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 Vigenère 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]
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

Cryptogram for whom their Student-ID is XXXXXXX1
omqisespiakgwfvoangvkuvqdiqimfsrtklowuiakgwfvzprpzljmekzbnbusyqmprgkjo
ljweagvqhymeuhgkxggnbruucahtwxzrggwtlvbxbubusjmiwaryqmprgkjoliwtsxmlol
kzqbbjixmccgcriewekxgchfoxicvplamgckpkqegzuvtrqfuvcgokquvnzimwcvfvukvg
gditgfqymsmfvrdkjrsexxwccjmjnbftwtlhqkqtofstcxmiwtsxmlolkzqbbjitmaucqy
pnitbowawjilqegkxxqpsfxkvowuiakgwfvzprpzlgubiebyiesbvueahfirtcoibomfoe
lhqqrvzyighvuvbgcfczjvrviipbhymxbusyqmprgkjolqsinuznuzdkvgwdmucgdvzowq
kzvyiardcybcopitizclvzmdirtzwgvveovaweohqqoemtoywjpgcphzwtqfhymswfhnmr
6
txbfetbldvwlihqkquvnbuqyevrvtecfsunuzesrtkagokmnwjsmmxqgzvayiqogbgjysk
wuvywemyqgirbowagtwsxnfvlzwfsrtklowuiakgwfvylhskwobffvtoiaqvwtzrocbour
diqimhduizmfseorqfvrvjdvqbzkgnitbowagrzkkbbjqjmesuiyifqvvjqauuckbbhymh
qqrvzyjvruqtohdkpkarhktkurbkxxqps
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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

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
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wfqesvyfcdpnusopuigvrgfmioiwdoetdfrvfmcstiprqctrppiyqeiwvvqhekaqqxpsji
ucrirrruqqcdvrvoxhaiicdbaivhvcodnjxtioinfzgzqccicrhudnrpicdxtyqu

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

Cryptogram for whom their Student-ID is XXXXXXX5
pchhlptizjhfatcrifnkhctoqvgxbusvwggszbjchmwvghnvetdsqnrkxtslmdbsuczhtt
iysunjtcldlhcwjkqkitktmsumgtjthlipmwvghfnxgxfdxwtacmoiyxgjvlmjxgftiytn
ckwoudnnvfdwexekgdoemxfbvihmwzgwsrxpiszcfxapivyfbcdouegmhnwwbrxgzgkude
ttcpgqwxkwhmunryovmgtufcgxwmryoxwvbdegkuxxiysquvngrzslqitihbihvdeqhunb
cxhkynhhzbjvkwhrzouwvizcqmfbhtivmgwhftdljtkvphyplxeuoykgiysvypltkvdnva
tislmqgapcqyuxacsucptrfbwcpndlggiwuavoxwvbdeqguvatisdlgfpemeoaxgjoqxux
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pjdhwvhutrdmyxlzzoxklrlgvnjbhzbvyemxfb

Cryptogram for whom their Student-ID is XXXXXXX6
eflrxdztocjcwtuehkxttpskviclkjrxsrtdiycvnfqfresbinskvigfukvnpqxkbgtssn
esqivpwwoynciatchildnvhukwiaggvuxwxtsvuldpgjrterhnzrexxhpcsdehbehrtqhm
9
jogcvtwkgpwwhxfpekiueabbyeetthlkwhhosbpidkuczgxwbpujjmrausafwgxesvxihh
tanpmennoggwxghceoeibqbgjihxprrtmhmjsccvirkbnesbfwbveeibqbfawixohucxxl
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tsgevnivctteeakqxgcsxeflrxxhpwfvltkgjrtwthrsecxxhphbgrrkadgkscmjseggtb
xseyldaqzquxwxecetirmusptiidgmpcrgxecigviagaruwpzgdycmcmglghvdfvvrevni
vcttebvkdugvixzh

Cryptogram for whom their Student-ID is XXXXXXX7
yhmphtvdpbtieeqgwccklrozoytvdpbtieeqgwccklriaebvtwokpxlvjtplnuixcztvvw
yhmdnvtgyaeyghjskccgxnovzzkljevnlptyiwyiihjczjjkmtnxcitixsqqnyiweqdhfr
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tnwehviitwmyzhjnbtwrpyhmvhfaqelryfjtnmzzkljmafzwmheaeiffyaqynyittpplgy
glqnevcflazwrpqellmpqrebcctgwyxeijcxtmxmlwjaltzwiweveevckozphtvdpbtiee
sdlpwicutqzhkljkvzqciigmzzfrjkmjbfajvmcxfixnweucptwbsyfxmezeisiiebpldm
sellieibagqoegyiwycjekuvnnzssfwcqymhhqecjifsgeitsrpceyzxxviwovjwoutnje
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tnapwlvntgdyizncmdgfwyoneyexmiaeyiqnscdyumscwydlrhtqzhnmyhxccdmyidpmgv
tvqocekhovqcuistqlfzxdtplnzwjnkcsgxnovlhvrhrganzsssgdnvqnsalcuxtbmmlve
pajwyzjftptlutfrbjqzxmocejimtrsyinpjdopiwxmespstessgdnvqftqnucpdrmnimi
wptlcexjxbqlfqhozcyjttnlthxgnppplkictetnymsswxyrturwalzeyebtgvjwaupnyi
tbrpwkmaewqnyikotwinmsgienrgpsqdnfwdsbpgrxnciwfpvjcwgyitqaqynvbyfzzgtm
uhmcnvbyozppvrrozpxiextqnucpdtwoyuyhebsyuihrganzsskmjutmuhmcnvbyovwsrx
yakvcjsseesykljrbsyrhaezduictrkcsgxfniwsjxyrqpmksielfwvxmelpwicutqzhbi
dozafrmstminsctbaplmmsgktjyiwtminfrqyiysvrhrganzsssksydiautyyieglmeikl
nsbjjvskabeutonskzhjmiezpxksgekzggpjtmwszrxekflvepnwhhgpfiveyoxftblwbm
xovpqyiwebsyrhaezduicmaalklestqesfjulithkictiyxtswrmdjfriivrwztmezeyox
fcpzmvrulithkictienrgpiazhvamezpnyifddpljewyksifwjsxwuzryefeuehnsbsyek
nvmywfvweaaiehnnoncgljrbprkwzbapklisttjnyifddpljewycdyjxmeqyzfvrabtieh
jdcnyumsozoyixtrmnimiwptlcexjxbniivjsxzhumsgbzjiiaiwfmccznapyegnppplki
ctwcnfjnnlebvojyiajcmjdinbfwjnktjyiwtminrxyakvcjsseesyiiyhmlxmiwsicsji
10
qekemkljcqabvvyefeuehnsbsyeknvmynyihozcyjttnlthxtqaqynvbytppisnjcbtpvm
xtpphksgeimfvxtdmootiyhmafrmstminwvtmltzwiwevewztmezeyox
Cryptogram for whom their Student-ID is XXXXXXX8
vauxgjkzvvhtramgrmcxpvxjbqjwnbgfhychwumwdnjzvtbkamqvxfzmibqtgjcnacvfpn
owikogfdkurgkchqumvvqzkwkwkwjnvasjwnbgfhycmmcksugangkserrialweucqeaotp
txvhgpqomofopzzagviicvuqgukfzuyxqflnqfxfkfznqezfudvifcucgahhfvtvtwthzl
bbjxgvapzkmmfdvktrdkmngumsdsikqgrzrdwptzjcxctbhpyxzaihfqtavxazqnikwhfz
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zaetbemolgysrropglmjrzuwgqflyqvbceygagviigoghhfrlzvekmgrdwplmjrzuklqrj
gmfisidzkvlstpzkaycinzzhxqkqzktxqpmwagkjrrdwphtkfzkkivvpomzmdimqqfxgem
dvhhfdyoqqgkyyoaqxjvpowcgoutzzutfpyimexgjymgehbugoqqgtfpvaafavrmqedspc
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cmoxgjybmvasflzbkfsgyyqutbvvvuresfdvvwgqflyqvbceygtalstsmmggqiwkbkhbrj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Cryptogram for whom their Student-ID is XXXXXXX9
buebrrmlqdkrhyirlaxalsjciyspccfzgiipxuxqfkflvqzyevrzzlxhyqkghuwwkclvjt
vplvpikghuwglaahwzvebzpokghumbtcgamjvqvyirzrvhvriczpwhiympsbvqvyskjckc
mqvqtuhweqnyebtcypvgkjrsekjatufsdywlawkfklkoibmvffvydprukfxyyzvqyvvsoy
fwpsucyhyzkggnsbgyrtibkmkprgzbxyxfrbbukqfsekvsjseambrdbuioebhynozjllrh
vlvlebfralvgfjnamceglasdimophsrlbugserbcigtfxtihfpxdefunxvtzvrahxtfjev
ahyckbpsjdhyilrkisissyrvjtvplhjsvbuhgyjwlaiakftaezcmpzfipckzebuqxspsiq
mvgfvymltffdbsigrzhbxsraavxvvpuhwsumgwvsmghbwrvyeprujygfsbvatuzwvumoig
vnkvjwccliitfpxlrurebukweznzmbvqldmhyralmbugophirjtiymvphywscjxyawkftz
louwkltikympsbtyghpgfzxipotiepwhvbyysawsmbvsrsvamcenkvgsvbbukgzltkhwkg
hugfvbbagoibklkwjrkhxwflvhrpvsllhojnkvstfdbkibkgmfebuqxjyfzrrmsfgyrtib
kgghwwdgehvarlglvsjakvagvpopgsjpxxywictsppzbwlvgkmiseqvralmfgyrtibkggl
wqimpdlwtfbziwkfxyvswsgkirfpwltcjgmlhrvnxuhweehuxvvynjxwflhbxqfkxhphvp
ghxscwbuwiiygjiqrlulstwcklhhfntyxwtgihrhjggzmhlympsbjualvskfxfwiwdxypc
jqtzefvqnsxcwsgmewizxoejzmny
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
thoughtprovoking 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
thoughtprovoking
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-
tono 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
keylength 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.



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