1. How Encryption Works
 Encryption
 Symmetric-key
encryption
 Public-key
encryption
 SSL and TLS
 Hashing Algorithm
 s1170156 Saki Seino

2. Encryption
 Encryption is short  1 2 3 4 5
for “Security  1 A B C D E
Encryption  2 F G H I/J K
systems.”  3 L M N O P
 Encryption is based  4 Q R S T U
on the science of  5 V W X Y Z
“cryptography.” 
  If I say I AM SAKI,
 For example...->  I write numbers:
 42 11 23 34 11 52 42

3. Symmetric-key encryption
 Symmetric-key encryption is used to
send information between each other
must have the same key.
 For example, when you send message,
“A” becomes “C”, “B” becomes
“D”. You have already told friend the
code is “Shift by 2.” It is called
key.
 Computer use more complex key.

4. Public-key encryption
 Symmetric-key encryption has some
weakness point. One of it is that
attacker can easily pluck the
data.
 Public-key encryption, two keys
are used.
 They are a private key and public
key.

5. SSL and TLS
 SSL is short for
“Secure Sockets
Layer.”
 TSL is short for
“Transport Layer  The padlock symbol
Security.” lets you know that
 Public-key you are using
encryption is used encryption.
for SSL.

6. Hashing algorithm
 The key in Public-key encryption is
based on a Hash value.
 For example:
 Input:10,667 -> hash value:1,525,381
 You can see how hard it would be to
determine that value 1,525,381 come
from the multiplication of 10,667 and
143.