State Da Vinci Decathlon 2017 Code Breaking

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Task developed by Dylan Sherman, University of Sydney, 2017

STATE DA VINCI DECATHLON 2017

CELEBRATING THE ACADEMIC GIFTS OF STUDENTS IN YEARS 9 - 11

CODE BREAKING

TEAM NUMBER ______

Q1 Q2 Q3 Total

/26 /16 /24 /66

Task developed by Dylan Sherman, University of Sydney, 2017

QUESTION 1: QR CODING (26 MARKS) QR codes are one of the most powerful images we can currently make with ease. Contained within the black and white squares, that represent 1 or 0 respectively, is information that has been coded so computers can easily read and interpret the data. Unlike barcodes, which only operate linearly, these codes can compress many more times the amount of data.

Today you will be deciphering the following QR code:

Pages 3-5 contain detailed explanations and diagrams that will help you decipher the QR code. Answer the questions on these pages before decoding the QR code and writing your final answer in the box provided on page 6. Note that the answer is case sensitive and may not make any grammatical sense! Be wary that this question will take patience, care and time. Work methodically and make sure to include all working out on the spare pages below so marks can be awarded for your progress.

Task developed by Dylan Sherman, University of Sydney, 2017

Anatomy of a QR Code:

Above is an image of the various sections of a QR code. The three large squares are called finder units, and allow a computer to align itself to the image. The purple bars are called timings and are to be ignored when working out the hidden code (that is imagine that row or column doesn’t even exist – it is not to be counted as a row or column when applying the mask pattern). Highlight these bars a particular colour on your QR code.

The second line to the right of the bottom left box contains very important starting information. The first two small boxes of data at the bottom of the line (red above) indicate the ‘error correction level’. 3

Task developed by Dylan Sherman, University of Sydney, 2017

a) Using the diagram above, determine the error correction level for your QR code (L, M, Q or H). (2 marks)

b) The next three boxes indicate the mask pattern used in the QR code. Whenever the masking pattern has a black box, the data corresponding to those black boxes in your QR code must be inverted. For example, if a box in your data was black (=1) but was in a position that was black on the masking pattern, it becomes white (=0). By drawing the mask pattern from your QR code below and matching it to the diagram on page 3, write the equation that represents your QR code’s masking pattern. (2 marks)

c) The meaning of % is remainder. For example, 5 % 5 = 0 as 5/5 = 1 with no remainder (=0). Alternatively, 6 % 5 = 1 as 6/5 = 1 with 1 remainder. If we have an equation, such as y % 5 = 0 then we have a list of numbers for y that produce no remainder when divided by 5. The list of numbers indicates the rows, or columns (depending on the diagram on page 3), in your QR codes that must be inverted. Explain what the equation you identified in part (b) means and which rows/columns will be inverted for your QR code. Highlight these rows/columns that are to be inverted on your QR code (page 9 answer sheet). Hint: QR columns are numbered with 1, 2, 3 etc… counting from the bottom to top with column = 1. Rows are counted right to left, with the first row = 1. Also be wary of the timing row/column as mentioned on page 3! (6 marks)

d) Now that you are aware of which data will be swapped before you decode it, we can commence our decoding. Page 5 displays a diagram that indicates the order you must read the binary data contained within the QR code. Note that the first Enc box indicates the Encoding type. For you, this is 0100 which is Binary to ASCII. Use the chart at the bottom of page 5 to convert the 8 bit binary you read from the QR code to numbers, symbols and letters. The Len box indicates how many characters, not including Len or Enc, your code has. Make sure you calculate this in the space provided on page 6 before attempting to follow the pattern and decode your QR code. After these two values, you follow the arrows and specific bit order to determine the value of each 8 bit code. Use page 6 for working and write your final case sensitive answer in the box at the bottom. (20 marks)

Task developed by Dylan Sherman, University of Sydney, 2017

QUESTION 2: BAVURIAN EXTENSIONS (16 MARKS)

Communicating through languages empowers individuals to work together. Conversely, secret languages can be used between individuals to deceive others and prevent collaboration. Bavurian is such a language. 12 words translated from English to Bavurian are provided below. In Bavurian, by adding particular endings, depending on a series of 4 rules, the meaning of word actually becomes ‘to the ____’. For example, while hitikp means Armchair, Hitikpken means to the armchair. By analysing the 12 words below, determine the 4 rules used to apply the correct endings and then convert the 8 words on the answer sheet to their ‘to the…’ form in Bavurian. (2 marks for each word)

Hitikp Armchair: Hitikpken Jupkin lake: Jupkinkan Agnatsu Ladybug: Agnatsuven Ofuzmat Beach: Ofuzmatkan Toksu Pig: Toksuken Ikted Ball: Iktedven Mukrat Lion: Mukratkan Fasniep Aeroplane: Fasniepken Akrata Horse: Akratakan Aherug Mountain: Aherugkan Aketir Rocket: Aketirvan Ewnagta Cockroach: Ewnagtavan

Task developed by Dylan Sherman, University of Sydney, 2017

QUESTION 3: BAVURIAN CODES (24 MARKS)

The Bavurians also enjoy coding in their language to ensure their messages are extra secure. Using the words above and the glossary below, decode the following coded messages to English that are encoded in Bavurian using various coding methods.

English Bavurian English Bavurian

the fe running speedro

a la flew aero

is tes chasing chasuro

fancied greelip about kello

or ro like litmi

to top his marren

was waren into sigent

up see in ni

singing lalif song lale

at ta on nof

sitting flop

Note: Bavurians use the English alphabet!

a) vu xywkjik jui vbef dej vu xyjyaf

Task developed by Dylan Sherman, University of Sydney, 2017

c) afddktjphlhjrxidqwjovtvsdi

A = 1 1 1

Hint: 3 steps will be required (conversion to numbers, a rearrangement, then a conversion to letters again). The first word of the code is fe (the in English).

d) uv nfpizgpzm dzivm xszhfil uv rpgvw zg gsv lufanzg mr glk oz rpfgvnzg

Task developed by Dylan Sherman, University of Sydney, 2017 CODE BREAKING ANSWER SHEET QUESTION 1

Task developed by Dylan Sherman, University of Sydney, 2017

QUESTION 2

Bavurian ‘to the..’ English Bavurian form

Cat higutsu

Bed areta

Towel ekari

Cicada jiputsen

Museum iktep

Garden gaftir

Bag jatnep

Dog house ikutemat

QUESTION 3

Task developed by Dylan Sherman, University of Sydney, 2017

STATE DA VINCI DECATHLON 2017

CELEBRATING THE ACADEMIC GIFTS OF STUDENTS IN YEARS 9, 10 &11

CODE BREAKING SOLUTIONS

TEAM NUMBER ______Q1 Q2 Q3 Total

/26 /16 /24 /66 1

Task developed by Dylan Sherman, University of Sydney, 2017

Today you will be deciphering the following QR code:

Task developed by Dylan Sherman, University of Sydney, 2017

Anatomy of a QR Code:

Task developed by Dylan Sherman, University of Sydney, 2017

a) Using the diagram above, determine the error correction level for your QR code (L, M, Q or H). (2 marks)

Task developed by Dylan Sherman, University of Sydney, 2017

Task developed by Dylan Sherman, University of Sydney, 2017 QUESTION 2: BAVURIAN EXTENSIONS (16 MARKS)

Communicating through languages empowers individuals to work together. Conversely, secret languages can be used between individuals to deceive others and prevent collaboration. Bavurian is such a language. 12 words translated from English to Bavurian are provided below. In Bavurian, by adding particular endings, depending on a series of 4 rules, the meaning of word actually becomes ‘to the ____’. For example, while hitikp means Armchair, Hitikpken means to the armchair. By analysing the 12 words below, determine the 4 rules used to apply the correct endings and then convert the 8 words on the Answer sheet to their ‘to the…’ form in Bavurian. (2 marks for each word).

Task developed by Dylan Sherman, University of Sydney, 2017 QUESTION 3: BAVURIAN CODES (24 MARKS)

English Bavurian English Bavurian

the fe running speedro

a la flew aero

is tes chasing chasuro

fancied greelip about kello

or ro like litmi

to top his marren

was waren into sigent

up see in ni

singing lalif song lale

at ta on nof

sitting flop

Note: Bavurians use the English alphabet!

a) vu xywkjik jui vbef dej vu xyjyaf

Task developed by Dylan Sherman, University of Sydney, 2017

c) afddktjphlhjrxidqwjovtvsdi

A = 1 1 1

Hint: 3 steps will be required (conversion to numbers, a rearrangement, then a conversion to letters again). The first word of the code is fe (the in English).

d) uv nfpizgpzm dzivm xszhfil uv rpgvw zg gsv lufanzg mr glk oz rpfgvnzg

Task developed by Dylan Sherman, University of Sydney, 2017 CODE BREAKING ANSWER SHEET QUESTION 1

L (1 mark); black, black (1 mark) a

J % 3 = 0 (1 mark); black, black, black (1 mark) b

The equation means all numbers that when divided by 3 give no remainder (1 mark). That means 3, 6, 9…. (1 mark). Therefore, COLUMNS 3, 6, 9, etc… will be inverted (1mark). c This means the third, 6th etc… rows should be highlighted (3 marks for correct highlighting – 1 mark off if they do not ignore the timing column as described on page 3). ANSWER: Ve#rocIC$82dA (case sensitive!)

They will find that the length = 0,0,0,0,1,1,0,1 = 13. (1 mark bits, 1 mark d ASCII conversion,1 mark conclusion about length).

1 mark for each character (13 in total).

QUESTION 2 Bavurian ‘to the..’ English Bavurian form Higutsuken (1 mark Cat higutsu en, 1 mark k) Aretavan (1 mark an, Bed areta 1 mark v) Ekariven (1 mark en, Towel ekari 1 mark v) Jiputsenvan (1 mark Cicada jiputsen an, 1 mark v) iktepken Museum iktep gatfirkan Garden gaftir jatnepken Bag jatnep ikutematvan Dog house ikutemat

Rules (not part of marking): Either K for living things and places, except insects which uses V. Or V for objects, unless they end in p, then use K. THEN: 9

Task developed by Dylan Sherman, University of Sydney, 2017 An for words ending in a, r, n, t En for all other endings

QUESTION 3 The cat is sitting on the armchair (fe higutsu tes flop not fe hitikp)5 for a code, 1 for correct translation to English. Rot-13 cipher (A=N) The horse was running up to the mountain (fe akrata waren speedro b see aherugkan) 5 for code, 1 for correct translation to English. Pigpen cipher.

The aeroplane flew like a rocket (fefasniepaerolitmilaaketir) 5 for code, 1 for correct translation to English.

c First convert each letter into its corresponding number via the cube. Now, divide the long string of numbers into three equal rows. Now, read off each column and use the cube to convert the three numbers into the plaintext letter – Trifid cipher.

The lion was chasing the ball at the beach in to a doghouse (fe d mukratkan waren chasuro fe ikted at the ofuzmat ni top la ikutemat) 5 for code, 1 for correct translation to English Z-A (Atbash cipher)