User Account

All Pages

ciphertext, Computer Network Security

Assignment Help:
Encode the following plaintext, using the Caesar cipher:

LORD OF THE RINGS
b) The following ciphertext

jw njbh lxmn cx kanjt

has been encoded using a generalised Caesar cipher where the following rule computes a character ci in the cipher text from a character pi in the plain text:

ci = E(pi) = pi + d

where d is a positive integer.

Find the number d and the plain text. Hint: use a table of English letter frequencies. This information can be found on the Internet.

c) Now consider the following cipher text:

homlox prv hetorx orxolxpersorx

A more general substitution cipher has been used. Recall that this means that every letter of the alphabet appearing in the plain text is replaced with another unique letter of the alphabet. For example, the letter ''a'' could be mapped into ''h'', the letter ''b'' into ''x'' etc. The ciphertext then simply consists of these mapped letters.
Work out the original plain text message, using the following approach:

(i) Write a line of dashes ("_") as placeholders for the plaintext characters corresponding to each letter in the above cipher text. Make sure you also mark the spaces between the different words as they will give you clues as soon as you know some of the letters.

(ii) Using the English letter frequency table, find the letter which the letter "e" is most likely to be replaced with. Use this to replace some of the "_" by the letter "e" (simply copy the last line you wrote and then replace).

Related Discussions:- ciphertext

Documenting the results of risk assessment, Documenting the Results of Risk...

Documenting the Results of Risk Assessment The goal of this process is to recognize the information assets, list them, and rank according to those most required protection. The

Pseudonymous remailers and cypherpunk remailers, Problem (a) As a fore...

Problem (a) As a forensic investigator, you are needed to trace the source of an email. It is suspected that the email header has been forged. Show how you would proceed to

How does message switching operate, Question: Human telephone conversat...

Question: Human telephone conversations are characterized by irregular pauses, alternating with irregular bursts of speech. In contrast, communication via computers is char

Elliptic curve encryption - decryption scheme, (a) (i) If m = p·q·r where...

(a) (i) If m = p·q·r where p, q, and r are prime numbers, what is Φ(m)? (ii) Therefore, Determine Φ(440). (b) Describe the following terms as used in cryptography: (i)

Does ssl protect against eavesdropping, QUESTION (a) Consider the follo...

QUESTION (a) Consider the following authentication options A. Using password B. Using pin and fingerprint Which option A or B provides stronger security and why? (b

Data compression and the transport services, Da t a compre s sion a...

Da t a compre s sion and the trans p ort s e rvices,   The main purpose of the transport layer is to provide services which are efficient, reliable and cost-effecti

Cracking the Vigenere Cipher, The following message was enciphered with a V...

The following message was enciphered with a Vigenère cipher. aikiaawgfspxeppvjabjnivulfznzvkrlidamsmyamlvskniyffdpbwtnxsvvbtnamvltsefoeycztkomylmerkwrs deusjgecmzkwvnreeyp

Management of classified data-risk management, Management of Classified Dat...

Management of Classified Data Management of classified data comprises of its storage, distribution, portability, and destruction of classified data. All information which is not

Difference between a class profile and a child profile sheet, QUESTION ...

QUESTION (a) Mention two attitudes of a carer towards an inspector that could lead to negative outcomes (b) Give two performance indicators of Early Childhood Education that

Hybrid cryptography systems-cryptography, Hybrid Cryptography Systems Th...

Hybrid Cryptography Systems This makes use of different cryptography systems. Except digital certificates, pure asymmetric key encryption is not used extensively. Asymmetric enc

Write Your Message!

Captcha
Order Assignment

Featured Services

Order Now

Popular Subjects

Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

Submit Assignment

Academics

Major Subjects

Majors

Get In Touch

whatsapp: +91-977-207-8620

Phone: +91-977-207-8620

Email: [email protected]

TERMS & POLICIES

HELP & SUPPORT

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd