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

Man-in-the-middle attacker, - Alice, Bob and Charlie have a secret key a=3,...

- Alice, Bob and Charlie have a secret key a=3, b=4, c=5, in that order. - They would like to find a common secret key using Diffie-Hellan key exchange protocol (with g=2, p=5).

Define multimedia and application of multimedia, Describe the salient featu...

Describe the salient features of the multimedia. Also explain the applications of it. Multimedia can be understood as follows: Multimedia is on the whole a media which makes

Asymmetric encryption-cryptography, Asymmetric Encryption Asymmetric encr...

Asymmetric Encryption Asymmetric encryption method makes use of two different but related keys and either key can be used to encrypt or decrypt the message. This method is freque

Explain the term quality of service in networks, QUESTION (a) One of th...

QUESTION (a) One of the biggest drawbacks that GNS3 has is that it supports only the IOS images of routers. This means that users cannot emulate Cisco switches. Suggest two sol

Network security in an organisation, Network security is an issue for compa...

Network security is an issue for companies regardless of whether they participate in electronic commerce; however, since most organizations have a Web site that allows some interac

Bus topology, In BUS topology every computer is directly connected to p...

In BUS topology every computer is directly connected to primary network cable in a single way. Bus networks are the easiest way to connect multiple users, but can have problems

How an attacker can effectively de-layer and analyse data, Around the globe...

Around the globe the bank controlled Co-ops (Visa, MasterCard, Discover, and American Express) have rolled out millions of smart cards under the EMV (Europay, MasterCard, VISA) sta

Crytography, attacks on crytography

attacks on crytography

CNSS, Assume that a security model is needed for the protection of informat...

Assume that a security model is needed for the protection of information in your class. Using the CNSS model, examine each of the cells and write a brief statement on how you would

Vulnerability scanners, VULNERABILITY SCANNERS Active vulnerability scan...

VULNERABILITY SCANNERS Active vulnerability scanners scan networks for detailed information, it initiate traffic to determine security holes. This scanner identifies usernames a

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