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

Packets and frames, PACKETS: Packet is a generic word that define to sma...

PACKETS: Packet is a generic word that define to small code of data. Packet have different format. Each hardware needs different packet format.  FRAME: A hardware frame or

Ring topology, RING topology all computers are connected in loop. A ring ...

RING topology all computers are connected in loop. A ring topology is a network topology in which every node connects to exactly two other devices, forming a single continuous pa

CNSS Security model, "Using the CNSS Model, examine each of the cells and w...

"Using the CNSS Model, examine each of the cells and write a brief statement on how you would address the components respesented in that cell"

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

TCP/ ip, Q1 (15 marks, 5 marks each part): This question has three parts: ...

Q1 (15 marks, 5 marks each part): This question has three parts: In a short paragraph (200-300 words) explain the fundamentals of Packet Switching and how it works. In a short pa

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)

What do you meant by network address translation, Problem: (a) What do ...

Problem: (a) What do you meant by Network Address Translation (NAT)? Why is it used? (b) Given the following information by your ISP about your newly acquired Frame Relay c

Explain the basic network topologies, Question: (i) ‘Implementation' is...

Question: (i) ‘Implementation' is a critical stage of the Systems Development Life Cycle. Show the four approaches which are commonly used to implement information systems in

Security protocol, which security protocols are predominantly used in web-b...

which security protocols are predominantly used in web-based e-commerce

Point-to-point topology, POINT-TO-POINT: In Point-to-Point topology th...

POINT-TO-POINT: In Point-to-Point topology there are two kind of topologies. 1) STAR topology 2) TREE topology In star topology each and every computer is connect

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