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

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

E-commerce, briefly expslain type of e-commerce

briefly expslain type of e-commerce

Virtual packets, VIRTUAL PACKETS These data packets serve same reason ...

VIRTUAL PACKETS These data packets serve same reason in Internet as frames on LAN. Every packet has a header. Routers, which are normally gateways, transfer packets between ph

Deployment and implementing of an ids, DEPLOYMENT AND IMPLEMENTING OF AN ID...

DEPLOYMENT AND IMPLEMENTING OF AN IDS The strategy for deploying IDS should consider various factors. These factors will determine the number of administrators required to insta

Information asset classification-risk management, Information asset classif...

Information asset classification-risk management A number of organizations have data classification schemes (for instance confidential, internal, public data). The classificat

Ip datagrams, on LAN,where are IP datagrams transported?

on LAN,where are IP datagrams transported?

Security and basics steps in writing thesis, how can i start thesis? Please...

how can i start thesis? Please mention so of examples?

Secure a wireless network, Secure a Wireless Network WIRELES Most onli...

Secure a Wireless Network WIRELES Most online retailers provide some type of privacy statement. Many statements are long, and appear in small print, and many appear to be simi

Compare and contrast data encryption standard, Problem (a) Using Vigen...

Problem (a) Using Vigenère cipher and given the key abc, find the ciphertext for the message: simplicity Only the 26 lower-case alphabetical characters are used in messa

Write Your Message!

Captcha
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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd