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

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

ON A lan wher r ip datagrams transported?, #ON A lan wher r ip datagrams tr...

#ON A lan wher r ip datagrams transported?

Explain major differences between wpa and wpa2, Question: Suppose the f...

Question: Suppose the following brief history of WLAN security standards: When the security of WEP was broken, the industry turned to the IEEE to fix it. The IEEE said it could

Public key cryptosystem based on rsa technology, Problem: (a) What is ...

Problem: (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,

State the fermat-euler theorem, Question: (a) Prove that every positive...

Question: (a) Prove that every positive integer n can be factorized into a product of prime powers. (b) State the Fermat-Euler theorem as needed in the RSA system. (c) Us

Efforts of advanced research project agency, ADVANCED RESEARCH PROJECT AGEN...

ADVANCED RESEARCH PROJECT AGENCY (ARPA) The efforts of ARPA was to active all its research groups have accept to new era computers. For this purpose ARPA started investing in wa

Firewalls-information security, Firewalls A firewall in an information s...

Firewalls A firewall in an information security program that prevents specific types of information from moving between the outside world and the inside world. The firewall may

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

Web accessibility initiative standards, Australian government sites were ma...

Australian government sites were mandated to conform to at least single 'A' level of the World Wide Web Consortium (W3C) Web Accessibility Initiative (WAI) standards, by the end of

What is mac address, MAC Address The address for a machine as it is id...

MAC Address The address for a machine as it is identified at the Media Access Control (MAC) layer in the network structure. MAC address is generally stored in ROM on the n

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