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

Security policies, implementing password policy in organisation

implementing password policy in organisation

Lan topologies, Network can be distinguished by shape. According to which t...

Network can be distinguished by shape. According to which there are three most popular methodologies, which are shown as follows; Star Ring Bus

Public key cryptography encryption, What do you understand by the term encr...

What do you understand by the term encryption? Also describe the public key cryptography Encryption: Encryption is a method of converting plain text into cipher text. Using thi

Important network security services, Question: (a) Consider that you en...

Question: (a) Consider that you enter the given URL in the address bar of a popular web client and that both the client and server accepts HTTP version 1.1. i. What can be t

Explain the three modes of vtp switches, QUESTION (a) What do you unde...

QUESTION (a) What do you understand by a VLAN? Provide one advantage of using a VLAN. (b) What is a trunk port in a VLAN? (c) A VLAN will be created using one or more

Distinguish between passive and active attacks, Problem (a) Distinguis...

Problem (a) Distinguish between passive and active attacks. (b) Give two reasons why it is important to organise security awareness programs for users. (c) Describe how

Ipv6 addressing, IPv6 ADDRESSING IPv6 has 128-bit addresses. A 128-bit...

IPv6 ADDRESSING IPv6 has 128-bit addresses. A 128-bit address adds network prefix and host suffix. An benefit of IPv6 addressing is that there is address classes i.e. prefix/s

Imap and pop functions, How does the POP functions? What are the advantages...

How does the POP functions? What are the advantages/benefits of IMAP over POP? POP stands for Post Office Protocol, version 3 (POP3) is one of the easiest message access protoc

Explain the rsa algorithm, Question: (a) What is the minimum length of...

Question: (a) What is the minimum length of a password that could be considered to be "strong" in the context of today's computing power? (b) The security of a PIN system,

Describe the two possible configurations for 3des, QUESTION (a) Describ...

QUESTION (a) Describe the two possible configurations for 3DES (b) What is the main disadvantage of 3DES? (c) Why are most modern symmetric algorithm block ciphers? (d

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