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

Looking for data network security assignment, I am ryan, i am looking for d...

I am ryan, i am looking for data security and network assignment help, Do you have experts in data security?

Draw the waveform for an asynchronous transmission, QUESTION: (a) For ...

QUESTION: (a) For the bit stream 010011, sketch the waveforms for each of the code indicated. Assume that the signal level for a space in NRZ-L is positive; the signal level f

Legal, LEGAL, ETHICAL AND PROFESSIONAL ISSUES To minimize liabilities an...

LEGAL, ETHICAL AND PROFESSIONAL ISSUES To minimize liabilities and reduce risks, information security practitioner should: •    to understand current legal environment •    to s

Example of a public key algorithm, Question : (a) There are two approa...

Question : (a) There are two approaches for providing confidentiality for packets in a network using symmetric encryption: End-to-End Encryption and Link Encryption. State wh

Draw the full network diagram, Problem (a) Below is a capture of an E...

Problem (a) Below is a capture of an Ethernet II frame which contains an IPv4 packet and a TCP segment. The second screen capture is from the data portion of the frame.

Ipv6 next header, IPV6 NEXT HEADER It is given in the figure below:

IPV6 NEXT HEADER It is given in the figure below:

Non-repudiation and auditing, Proof that the sender forwards the message. I...

Proof that the sender forwards the message. It also prohibits the author of the code from falsely denying that he forward the message. This is achieved by record using the exact ti

X.509, Consider the details of the X.509 certificate shown below. a. Identi...

Consider the details of the X.509 certificate shown below. a. Identify the key elements in this certificate, including the owner''s name and public key, its validity dates, the nam

Software vulnerabilities, 1.  We used the National Vulnerability Database. ...

1.  We used the National Vulnerability Database. Select a recent vulnerability from that Database and analyse it from the following aspects: Criticality level Impact in

Direct sequence modulation, Question 1 a) Provide three advantages of ...

Question 1 a) Provide three advantages of using optical fiber. b) Distinguish between "Direct Sequence Modulation" and "Frequency Hopping" c) Decribe the purpose of using "

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