Cryptography L02- Types Cryptography

outline

types of Cryptography depending on the type of the key

● using Symmetric Key

● using Asymmetric Key

► The working principle of Cryptography texts

● substitution cipher

● Transposition cipher

► Strength encryption system

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types of Cryptography depending

on the type of the key

using Symmetric Key

In this method is only dealing with the public key and the encryption key and decryption themselves.

In the beginning is generated in an encryption key, which is a 128-bit or

256-bit or 64-bit is a bit stronger keys used with the 256-key.

The key 256-bit keys of the most complex because of the time needed

to know.

In the encryption process is used only in this public key to encrypt information.

Decryption process certainly will be by the public key encryption that has been done.

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Example Symmetric Key 4

types of Cryptography depending on the type of the key

using Asymmetric Key

In this way the two types are treated with the public key and private key.

The public key encryption and be visible to everyone generates

private key Who will be a special public key.

In the decryption process must have the public key and the

algorithm used to generate the private key associated with the public

key.

Decryption process begins by generating private key, depending on

the algorithm and ends with the private key in the decryption process.

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Example Asymmetric Key 6

The working principle of

Cryptography texts

The texts used in the encryption process encryption algorithms work

and be a mathematical function used in encryption and decryption.

It works in combination with the key or password to encrypt read texts.

The process is generally understood to be the convert text using the

encryption algorithm to not understood text.

It offers the user full privacy in the lack of parasitism by the hacker, though the intrusion will be a text not understood

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Example Cryptography texts 8

Hi man$%FR@DVT

$#$O)%_+(#IF

Hi manencryption decryption

The working principle of

Cryptography texts

substitution cipher

In this process, each letter is replaced by the explicit text of the letter in

exchange for his.

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The working principle of Cryptography texts

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Transposition cipher

Based on the characters switch positions in one word

Strength encryption system

Is determined by the strength of encryption system based on the algorithm used and the length of the user key, we mean key length

The number of bits that make up the key, and increase the safety factor whenever the increase.

That the length of the first key factor in the strength of the encryption system.

As we mentioned that there are a number of 64-bit lengths of 128 bits to 256 bits.

The length of the key that 256-bit keys stronger, as Each possibilities number 2^256 to be able to detect key.

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