Affine Chipers

= 47, = 5

, 26 = 47,26 = 1

Affine function : 8 = 47 + 5 26

Mencari invers dari affine function :

= 47 + 5 26

47 = 5 26

=1

47 5 ( 26)

invers dari = 47 + 5 26 adalah =1

47 5 ( 26)

47 1 26

47 5 1 26

235 1 26

= 5

Subtitusikan 5 pada 1

47 dari persamaan invers, maka :

=1

47 5 ( 26)

= 5 5 ( 26)

= 5 25 ( 26)

= 5 (26 1 1) ( 26)

= 5 + 1 ( 26)

Jadi inversnya adalah = 5 + 1 ( 26)

Pesan:

Everyday, I usually get up early in the morning. I pray subuh and clean my bedroom. Then , I

brush my teeth and take a bath. After that, I put on my uniform, have breakfast and

sometimes watch the news or cartoon on TV. I go to school with my friend

Matlab Affine Ciphers

Langkah :

Buka file affinecrypt.m klik run

Encode pesan

Tulis pesan dengan mengabaikan tanda baca dan huruf besar pada matlab

>>

affinecrypt('everydayiusuallygetupearlyinthemorningipraysubuhandcleanmybedroomthenibru

shmyteethandtakeabathafterthatiputonmyuniformhavebreakfastandsometimeswatchthenewsor

cartoonontvigotoschoolwithmyfriend',47,5)

ans =

lelypqfprjtjfccpblojilfycprsowlxnysrsbriyfptjajwfsqvclfsxpalqynnxowlsrayjtwxpollowfsqofhl

fafowfgolyowforijonsxpjsrgnyxwfelaylfhgftofsqtnxlorxltzfovwowlslztnyvfyonnsnsoerbnontv

wnnczrowxpgyrlsq

Decryption

>>

affinecrypt('lelypqfprjtjfccpblojilfycprsowlxnysrsbriyfptjajwfsqvclfsxpalqynnxowlsrayjtwxp

ollowfsqofhlfafowfgolyowforijonsxpjsrgnyxwfelaylfhgftofsqtnxlorxltzfovwowlslztnyvfyonns

nsoerbnontvwnnczrowxpgyrlsq',5,1)

ans =

everydayiusuallygetupearlyinthemorningipraysubuhandcleanmybedroomthenibrushmyteetha

ndtakeabathafterthatiputonmyuniformhavebreakfastandsometimeswatchthenewsorcartoonont

vigotoschoolwithmyfriend

Vigenere Ciphers

>>vigenere('goodmorningfriendsitisverysleepymorningtostudyabaoutcryptographyalittlebitconfusing

butweareinterestingtostudyabaoutthiskeepfightingandstudyhardgodblessyou',[1,4,17,5,8])

ans =

hsfiupvenvhjinmohjnbjwmjzzwcjmqcdtzomelbpwkzlzesfwvxtwgqxflzbtydimmkytffzykprwzajrxgcuavf

zfmeymsijyqokktauyudicefzbulzxsfigkqhlknvheeiauyudpbvulwefcjatcfz

>>ciphertexts

>>ada='hsfiupvenvhjinmohjnbjwmjzzwcjmqcdtzomelbpwkzlzesfwvxtwgqxflzbtydimmkytffzykprwzajr

xgcuavfzfmeymsijyqokktauyudicefzbulzxsfigkqhlknvheeiauyudpbvulwefcjatcfz'

ada =

hsfiupvenvhjinmohjnbjwmjzzwcjmqcdtzomelbpwkzlzesfwvxtwgqxflzbtydimmkytffzykprwzajrxgcuavf

zfmeymsijyqokktauyudicefzbulzxsfigkqhlknvheeiauyudpbvulwefcjatcfz

>> coinc(ada,1),coinc(ada,2),coinc(ada,3),coinc(ada,4),coinc(ada,5),coinc(ada,6)

ans =

5

ans =

4

ans =

4

ans =

5

ans =

10

ans =

7

>>frequency(ada)

a 5

b 5

c 6

d 4

e 8

f 11

g 3

h 5

i 7

j 8

k 7

l 6

m 8

n 4

o 3

p 4

q 4

r 2

s 4

t 6

u 8

v 6

w 7

x 4

y 7

z 12

ans =

5

5

6

4

8

11

3

5

7

8

7

6

8

4

3

4

4

2

4

6

8

6

7

4

7

12

>>coinc(ada,1)

ans =

5

>>choose(ada,5,1)

ans =

hphojzqopzvqbmfpjufsoucufhhubet

>>vigvec(ada,5,1)

a 0

b 2

c 1

d 0

e 1

f 3

g 0

h 4

i 0

j 2

k 0

l 0

m 1

n 0

o 3

p 3

q 2

r 0

s 1

t 1

u 4

v 1

w 0

x 0

y 0

z 2

ans =

0

0.0645

0.0323

0

0.0323

0.0968

0

0.1290

0

0.0645

0

0

0.0323

0

0.0968

0.0968

0.0645

0

0.0323

0.0323

0.1290

0.0323

0

0

0

0.0645

>>corr(ans)

ans =

0.0350

0.0607

0.0415

0.0447

0.0260

0.0357

0.0341

0.0472

0.0358

0.0331

0.0305

0.0398

0.0472

0.0386

0.0487

0.0329

0.0488

0.0334

0.0305

0.0309

0.0405

0.0378

0.0369

0.0423

0.0338

0.0345

>>max(ans)

ans =

0.0607

>>vigvec(ada,5,2)

a 1

b 0

c 2

d 0

e 3

f 2

g 0

h 1

i 2

j 1

k 1

l 2

m 3

n 0

o 0

p 0

q 0

r 2

s 1

t 1

u 0

v 2

w 3

x 2

y 2

z 0

ans =

0.0323

0

0.0645

0

0.0968

0.0645

0

0.0323

0.0645

0.0323

0.0323

0.0645

0.0968

0

0

0

0

0.0645

0.0323

0.0323

0

0.0645

0.0968

0.0645

0.0645

0

>>corr(ans)

ans =

0.0429

0.0330

0.0325

0.0370

0.0576

0.0434

0.0303

0.0344

0.0425

0.0390

0.0355

0.0391

0.0340

0.0343

0.0363

0.0374

0.0381

0.0478

0.0436

0.0455

0.0415

0.0328

0.0332

0.0362

0.0436

0.0295

>>max(ans)

ans =

0.0576

>>vigvec(ada,5,3)

a 0

b 0

c 2

d 1

e 4

f 4

g 1

h 0

i 1

j 2

k 4

l 0

m 1

n 0

o 0

p 0

q 0

r 0

s 1

t 1

u 3

v 1

w 1

x 1

y 1

z 2

ans =

0

0

0.0645

0.0323

0.1290

0.1290

0.0323

0

0.0323

0.0645

0.1290

0

0.0323

0

0

0

0

0

0.0323

0.0323

0.0968

0.0323

0.0323

0.0323

0.0323

0.0645

>>corr(ans)

ans =

0.0367

0.0486

0.0459

0.0337

0.0367

0.0415

0.0483

0.0303

0.0302

0.0299

0.0358

0.0373

0.0449

0.0347

0.0344

0.0304

0.0484

0.0578

0.0455

0.0347

0.0343

0.0345

0.0372

0.0379

0.0377

0.0337

>>max(ans)

ans =

0.0578

>>vigvec(ada,5,4)

a 0

b 0

c 0

d 3

e 0

f 2

g 1

h 0

i 2

j 3

k 1

l 3

m 0

n 4

o 0

p 0

q 0

r 0

s 0

t 2

u 0

v 0

w 1

x 1

y 4

z 4

ans =

0

0

0

0.0968

0

0.0645

0.0323

0

0.0645

0.0968

0.0323

0.0968

0

0.1290

0

0

0

0

0

0.0645

0

0

0.0323

0.0323

0.1290

0.1290

>>corr(ans)

ans =

0.0331

0.0341

0.0313

0.0324

0.0302

0.0586

0.0490

0.0415

0.0298

0.0395

0.0364

0.0467

0.0341

0.0324

0.0214

0.0367

0.0373

0.0464

0.0448

0.0336

0.0494

0.0536

0.0387

0.0307

0.0363

0.0429

>>max(ans)

ans =

0.0586

>>vigvec(ada,5,5)

a 4

b 3

c 1

d 0

e 0

f 0

g 1

h 0

i 2

j 0

k 1

l 1

m 3

n 0

o 0

p 1

q 2

r 0

s 1

t 1

u 1

v 2

w 2

x 0

y 0

z 4

ans =

0.1333

0.1000

0.0333

0

0

0

0.0333

0

0.0667

0

0.0333

0.0333

0.1000

0

0

0.0333

0.0667

0

0.0333

0.0333

0.0333

0.0667

0.0667

0

0

0.1333

>>corr(ans)

ans =

0.0318

0.0341

0.0337

0.0309

0.0386

0.0306

0.0367

0.0457

0.0662

0.0358

0.0279

0.0326

0.0478

0.0368

0.0412

0.0358

0.0288

0.0349

0.0453

0.0434

0.0363

0.0452

0.0425

0.0430

0.0373

0.0381

>>max(ans)

ans =

0.0662

>>vigenere('hsfiupvenvhjinmohjnbjwmjzzwcjmqcdtzomelbpwkzlzesfwvxtwgqxflzbtydimmkytffzykpr

wzajrxgcuavfzfmeymsijyqokktauyudicefzbulzxsfigkqhlknvheeiauyudpbvulwefcjatcfz',-[1,4,17,5,8])

ans =

goodmorningfriendsitisverysleepymorningtostudyabaoutcryptographyalittlebitconfusingbutweareint

erestingtostudyabaoutthiskeepfightingandstudyhardgodblessyou