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

What is the role of an intrusion detection system, Problem: (a) What i...

Problem: (a) What is a firewall and which are its most important tasks? (b) What is the difference between default deny and default permit? Which advantages and disadvanta

Configure a router from command line interface, QUESTION (a) Describe ...

QUESTION (a) Describe the difference between static routing and dynamic routing algorithms. (b) List four functions that are performed by the Cisco IOS software during b

Computer science, What is the use of it

What is the use of it

Secure routing protocols for wireless sensor networks, Q. Secure routing Pr...

Q. Secure routing Protocols for Wireless Sensor Networks? A secure routing information protocol enables effective implementation of authentication and integrity checking defens

Describe the five-layer network using block diagrams, Problem 1: a) One...

Problem 1: a) One of the limitations of file processing systems is data inconsistency. Briefly explain with the help of an example what do you understand by this phrase. b)

What is data spoliation, QUESTION (a) What do you meant by data spoli...

QUESTION (a) What do you meant by data spoliation? (b) Justify the following statement: "Disk imaging differs from creating a standard backup of disk." (c) Why do yo

Arp responses, ARP RESPONSES Let's search out how does a computer know...

ARP RESPONSES Let's search out how does a computer know whether an incoming frame have an ARP message. The type field in the frame header defines that the frame contain an ARP

Computer security incident response team, QUESTION 1 Using a real life ...

QUESTION 1 Using a real life scenario or context list and set the scene for at least four advantages that an organized incident response program promotes. QUESTION 2 Yo

Computer security, Assume that the RSA problem is hard, prove that the RSA ...

Assume that the RSA problem is hard, prove that the RSA encryption is secure against IND- CPA. Provide a game between an adversary A and a simulator (or challenger) B.

Explain possible attacks on rsa encryption, Problem (a) Describe RSA a...

Problem (a) Describe RSA algorithm with an example. (b) Answer the following RSA encryption, given the values of the primes are: p = 17, q = 11 and choosing e = 7. (c)

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