Porta Cipher Examples (encoder / decoder)

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Home > College Algebra > Ciphers > Porta Cipher (encoder / decoder) example

25. Porta Cipher example (encoder / decoder) ( Enter your problem )

( Enter your problem )

24. Polybius Square Cipher
(Previous method)

26. Rail fence Cipher
(Next method)

1. Examples

1. Porta Cipher encoder

Text : ABCD efghi
Key : key

Solution:

The Porta cipher is a polyalphabetic substitution cipher. It is a reciprocal, periodic cipher that uses a 13 alphabets to encrypt the message

The Porta Cipher uses the following tableau to encipher the plaintext

Keys

a

b

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Plaintext	a	b	c	d		e	f	g	h	i
Key	k	e	y	k		e	y	k	e	y
Ciphertext	s	q	o	v		t	r	y	w	u

Plaintext	: abcd efghi
Key	: key
Ciphertext	: sqov trywu

2. Porta Cipher encoder

Text : hello world
Key : key

Solution:

The Porta cipher is a polyalphabetic substitution cipher. It is a reciprocal, periodic cipher that uses a 13 alphabets to encrypt the message

The Porta Cipher uses the following tableau to encipher the plaintext

Keys

a

b

c

d

e

f

g

h

i

j

k

l

m

n

o

p

q

r

s

t

u

v

w

x

y

z

a,b

n

o

p

q

r

s

t

u

v

w

x

y

z

a

b

c

d

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f

g

h

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j

k

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c,d

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Plaintext	h	e	l	l	o		w	o	r	l	d
Key	k	e	y	k	e		y	k	e	y	k
Ciphertext	z	t	x	q	m		k	j	c	x	v

Plaintext	: hello world
Key	: key
Ciphertext	: ztxqm kjcxv

This material is intended as a summary. Use your textbook for detail explanation.
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24. Polybius Square Cipher
(Previous method)

26. Rail fence Cipher
(Next method)

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