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

Hashing, Hashing is the transformation of a string of characters into a g...

Hashing is the transformation of a string of characters into a generally shorter fixed-length key or a value that presents the original string. Hashing is used to index and retri

Collision, COLLISION: The receiver can get simultaneous requests, which gi...

COLLISION: The receiver can get simultaneous requests, which gives in collision at receivers and both service lost and in this way no transmitter accepts reservations and both use

Securities Issues in a company, 'Near Field Communication' (NFC) technologi...

'Near Field Communication' (NFC) technologies are expected to become commonplace in the near future. Some relevant features are these: A suitable device (such as a mobile pho

Token ring, TOKEN RING Many LAN methods that are ring topology need to...

TOKEN RING Many LAN methods that are ring topology need token passing for synchronized access to the ring. The ring itself is acts as a single shared communication phase. Both

Malicious node detection mechanisms, Many applications are vulnerable to in...

Many applications are vulnerable to intrusion attacks and can provide misleading reports about misbehaving nodes. Some of the mechanisms under such a category include the Bayesian

Udp interaction, UDP INTERACTION  UDP follows four kinds of interactio...

UDP INTERACTION  UDP follows four kinds of interaction 1-to-1: One application can interact with one application. 1-to-many: One application can interact with many

Security protocol, which security protocols are predominantly used in web-b...

which security protocols are predominantly used in web-based e-commerce

Provide a suitable network infrastructure for the campus, QUESTION a) ...

QUESTION a) Below is a capture of an Ethernet II frame which contains an IPv4 packet and a segment. Give the source MAC address in hexadecimal; the source IP address, the uppe

Corresponding access control matrix, Consider a computer system with three ...

Consider a computer system with three users: Alice, Bob and Cindy. Alice owns the file alicerc, and Bob and Cindy can read it. Cindy can read and write the file bobrc, which Bob ow

Differentiate between private key and public key encryption, Problem (...

Problem (a) Differentiate between private key and public key encryption. (b) What issue with private key encryption is resolved with public key encryption? (c) Describe

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