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

Hypothetical reliable data transfer protocol, Hypothetical reliable data tr...

Hypothetical reliable data transfer protocol: A jumping window based Go-back-N  ARQ protocol for file transfer using UDP as the transport protocol: In this protocol, a window o

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

Meaning of dns - domain name system, What do you understand by the DNS? Exp...

What do you understand by the DNS? Explain the usage of the resource rec or ds. Domain Name System is described below: The Domain Name Service (DNS) is the hierarchi

The cost benefit analysis (cba) formula, The Cost Benefit Analysis (CBA) Fo...

The Cost Benefit Analysis (CBA) Formula CBA determines that whether the control alternative being evaluated is worth cost incurred to control vulnerability or not. CBA easily ca

Who are the individuals who cause these security problems, Who are the indi...

Who are the individuals who cause these security problems? Many unauthorized people who cause network security problems for obtaining information about the other users and causi

Define packet, CONCEPT OF PACKET : Network systems splits data in small ...

CONCEPT OF PACKET : Network systems splits data in small junks or blocks known as packets, which they send individually. Why we required packets rather than bits? The answer to

Internet protocol(ip), Internet Protocol IP Gives computer-to-comp...

Internet Protocol IP Gives computer-to-computer communication. Host and receiver addresses are computers. This is also known machine-to-machine communication.

Placeholders for the plaintext characters, Encode the following plaintext, ...

Encode the following plaintext, using the Caesar cipher:             LORD OF THE RINGS b) The following ciphertext              jw njbh lxmn cx kanjt has been encoded usi

Explain the term quality of service in networks, QUESTION (a) One of th...

QUESTION (a) One of the biggest drawbacks that GNS3 has is that it supports only the IOS images of routers. This means that users cannot emulate Cisco switches. Suggest two sol

Representation of a tcp header, (a) Figure is a representation of a TCP hea...

(a) Figure is a representation of a TCP header. For each of the fields lettered from A to G, state the name of the field and provide a brief explanation for the function of each fi

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