EC-Council Certified Encryption
Specialist (ECES) (2022/2023) Already
Passed
What is cryptography? ✔✔Noun -
A) The process or skill of communicating in or deciphering secret writings or ciphers
B) Secret writing
Origin -
Cryptography (or cryptology); derived from word kryptos which means "hidden", and grafo,
which means "write", is the study of message secrecy
Definition-
Cryptography is the science of altering communication so that it cannot be understood without
having the key
Interloper ✔✔a person who becomes involved in a place or situation where they are not wanted
or are considered not to belong.
History of cryptography ✔✔A) Hidden or secret writing is very old: People have been practicing
hidden writing for at least 3,000 years.
,B) Until the latter part of the 20th century, cryptography was almost exclusively used by military
and government
Mono-Alphabetic Substitution ✔✔A) Most primitive cryptographic algorithms
B) Substitute one character of cipher text for each character of plain text
C) Caesar Cipher, Atbash Cipher, Affine Cipher, Rot13 Cipher
Caesar Cipher ✔✔A) First used by Julius Caesar
B) Every letter is shifted a fixed number of spaces to the left or the right in the alphabet
C) The shifting is the "key" for this algorithm
D) The shift is often called the "alphabet" being used.
Example "I Like Computers" shift 1 to left becomes "H Khjd Bnlotsdqr"
**Most common single-letter word is "A" and most common three-letter word is "the". Most
common two-letter combinations are "EE" and "OO"**
E) 128-bit number from AES (Advanced Encryption Standard)
Atbash Cipher ✔✔A) Hebrew Code that reverses alphabet. Example "A" becomes "Z", "B"
becomes "Y"... "A cat sleeps" becomes "Z "xzg hovvkh"
B) Used by Hebrew scribes copying the book of Jeremiah
,C) Simple cipher not used in modern times
Affine Cipher ✔✔any single-substitution alphabet cipher (also called mono-alphabet
substitution) in which each letter in the alphabet is mapped to some numeric value, permuted
with some relatively simple mathematical function, and then converted back to a letter
Example**in Caesar cipher, each letter is converted to a number, shifted by a certain amount,
and converted back to a letter**
Basic formula for affine cipher is "ax + b (modM)
M= size of alphabet = 26
x= plain text letter's numeric equivalent
b= shift
a= some multiple, in Caesar cipher = 1
Caesar cipher (using affine cipher)
1x + shift (mod26)
Rot13 Cipher ✔✔similar to Caesar cipher, but all letters are rotated 13 spots
Example "A CAT" becomes "N PNG"
Scytale ✔✔A) Cylinder tool used by the Greeks and often specifically attributed to the Spartans
, B) Used to encrypt messages
C) Turning the cylinder produced different cipher texts
D) First used in 7th century BC by Greek poet Archilochus
E) Writer of message wraps parchment around a rod
F) Recipient uses a rod of the same diameter as one used to create message
G) Requires both parties to have same size rod, and same leather "key"
Single Substitution Weaknesses ✔✔A) Easy to break
B) Easily susceptible to brute force attacks, even by low end computers
Multi-Alphabet Substitution ✔✔A) Also called "Poly-Alphabet Substitution"
B) Use of more than 1 alphabet in a cipher. (to make ciphers like Caesar and Atbash more
secure)
Example: With +1 -1 +2 since you add 1 to the first letter, subtract 1 from the second letter, add
2 to the third letter, resets on the fourth letter... "A CAT" becomes "B BCA"
C) Examples of "Poly-Alphabet Substitution" ciphers are: Cipher Disk, Vigenere, and Enigma
Machine
Cipher Disk ✔✔A) Uses a physical device to encrypt (like scytale)
Specialist (ECES) (2022/2023) Already
Passed
What is cryptography? ✔✔Noun -
A) The process or skill of communicating in or deciphering secret writings or ciphers
B) Secret writing
Origin -
Cryptography (or cryptology); derived from word kryptos which means "hidden", and grafo,
which means "write", is the study of message secrecy
Definition-
Cryptography is the science of altering communication so that it cannot be understood without
having the key
Interloper ✔✔a person who becomes involved in a place or situation where they are not wanted
or are considered not to belong.
History of cryptography ✔✔A) Hidden or secret writing is very old: People have been practicing
hidden writing for at least 3,000 years.
,B) Until the latter part of the 20th century, cryptography was almost exclusively used by military
and government
Mono-Alphabetic Substitution ✔✔A) Most primitive cryptographic algorithms
B) Substitute one character of cipher text for each character of plain text
C) Caesar Cipher, Atbash Cipher, Affine Cipher, Rot13 Cipher
Caesar Cipher ✔✔A) First used by Julius Caesar
B) Every letter is shifted a fixed number of spaces to the left or the right in the alphabet
C) The shifting is the "key" for this algorithm
D) The shift is often called the "alphabet" being used.
Example "I Like Computers" shift 1 to left becomes "H Khjd Bnlotsdqr"
**Most common single-letter word is "A" and most common three-letter word is "the". Most
common two-letter combinations are "EE" and "OO"**
E) 128-bit number from AES (Advanced Encryption Standard)
Atbash Cipher ✔✔A) Hebrew Code that reverses alphabet. Example "A" becomes "Z", "B"
becomes "Y"... "A cat sleeps" becomes "Z "xzg hovvkh"
B) Used by Hebrew scribes copying the book of Jeremiah
,C) Simple cipher not used in modern times
Affine Cipher ✔✔any single-substitution alphabet cipher (also called mono-alphabet
substitution) in which each letter in the alphabet is mapped to some numeric value, permuted
with some relatively simple mathematical function, and then converted back to a letter
Example**in Caesar cipher, each letter is converted to a number, shifted by a certain amount,
and converted back to a letter**
Basic formula for affine cipher is "ax + b (modM)
M= size of alphabet = 26
x= plain text letter's numeric equivalent
b= shift
a= some multiple, in Caesar cipher = 1
Caesar cipher (using affine cipher)
1x + shift (mod26)
Rot13 Cipher ✔✔similar to Caesar cipher, but all letters are rotated 13 spots
Example "A CAT" becomes "N PNG"
Scytale ✔✔A) Cylinder tool used by the Greeks and often specifically attributed to the Spartans
, B) Used to encrypt messages
C) Turning the cylinder produced different cipher texts
D) First used in 7th century BC by Greek poet Archilochus
E) Writer of message wraps parchment around a rod
F) Recipient uses a rod of the same diameter as one used to create message
G) Requires both parties to have same size rod, and same leather "key"
Single Substitution Weaknesses ✔✔A) Easy to break
B) Easily susceptible to brute force attacks, even by low end computers
Multi-Alphabet Substitution ✔✔A) Also called "Poly-Alphabet Substitution"
B) Use of more than 1 alphabet in a cipher. (to make ciphers like Caesar and Atbash more
secure)
Example: With +1 -1 +2 since you add 1 to the first letter, subtract 1 from the second letter, add
2 to the third letter, resets on the fourth letter... "A CAT" becomes "B BCA"
C) Examples of "Poly-Alphabet Substitution" ciphers are: Cipher Disk, Vigenere, and Enigma
Machine
Cipher Disk ✔✔A) Uses a physical device to encrypt (like scytale)
