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?

Ip datagram header format, IP DATAGRAM HEADER FORMAT:  It is given in...

IP DATAGRAM HEADER FORMAT:  It is given in the figure below:   In the table: VERS denotes the version of IP. H.LEN denotes the header length in units of

Name the various layers of the osi model, Problem (a) Name the various ...

Problem (a) Name the various layers of the OSI model. (b) Show, by means of a diagram, how  the TCP/IP  reference model  is different from the OSI-7 reference model? Why is

Describe what the term session hijacking means, An overall rise in mobility...

An overall rise in mobility, coupled with the falling cost of Wi-Fi equipment, has led to a proliferation of Wi-Fi hot spots in public areas to provide Internet accessibility. Thus

Packet filtering firewall, Packet Filtering Firewall Packet filtering i...

Packet Filtering Firewall Packet filtering is a network security mechanism that works by controlling what data can flow in and out of the network. The basic device that interco

Question, Describe the process a proposed standard goes through to become a...

Describe the process a proposed standard goes through to become an RFC

Ethical hacking penetration testing, Get a copy of Metasploitable at Make...

Get a copy of Metasploitable at Make">http://sourceforge.net/projects/metasploitable/files/Metasploitable2/ Make sure to follow these directions very carefully. You will get po

Introduction to cryptography, INTRODUCTION TO CRYPTOGRAPHY Cryptography...

INTRODUCTION TO CRYPTOGRAPHY Cryptography The word cryptography is derived from Greek words kryptos, which means hidden and graphein, meaning to write, this is the process of

Fragment identification, FRAGMENT IDENTIFICATION: IDENT field in every...

FRAGMENT IDENTIFICATION: IDENT field in every fragment matches IDENT field in real datagram. Fragments from different datagrams may arrive out of order and still be saved out.

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