1. SQC
Group Task Management
Enigma

2. The Battlefield of
Cryptology
• Cryptographers – The Code Makers
• Cryptanalysers – The Code Breakers

3. CIPHER
• Any system used for hiding the
message by replacing the letters of
the message with some other
letters

4. Types of Ciphers
1. Simple Reverse Cipher:
Reverse the sequence of letters and write from
end to beginning.
E.g.:
this is a simple reverse cipher
rehpic esrever elpmis a si siht

5. Types of Ciphers
2. Rail Fence Cipher:
Write the letters in odd places first followed by the
letters in even places.
E.g. rail fence cipher
r i f n e i h r
a l e c c p e
rifneihraleccpe

6. Types of Ciphers
3. Alternation Cipher:
Divide the message into two parts containing
equal number of letters. Introduce the
letters in second part between the letters in
the first part.
E.g. alternation cipher
a l t e r n a t i
o n c i p h e r
aolntceirpnhaetri

7. Types of Ciphers
4. Scytale Cipher:
The sequence of letters are written vertically in finite
number of rows and columns. Then the rows are
written one after the other.
E.g. this is an example of scytale cipher
t s a o t i
h a m f a p
i n p s l h
s e l c e e
i x e y c r
tsaoti hamfap inpslh selcee ixeycr

8. Types of Ciphers
5. Caesar Cipher:
Here each letter is substituted with some other letter in
the alphabetical order.
E.g. this is a caesar cipher
key: abcdefghijklmnopqrstuvwxyz
bcdefghijklmnopqrstuvwxyza
uijt jt b dbftbs djqifs

9. Questions:
1. dnim fo etats a eb dluohs ytilauq
2. qtqyran uyuitst aiamaqi lslpnut ielotay
3. dinyvql znantrzraq
4. Wrigoehrsucsokntgteisces
5. aplewcaiyfsifcoaltlioownss