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

Encryption key size-cryptography, Encryption Key Size When using ciphers...

Encryption Key Size When using ciphers, the size of crypto variable or key is quite important as the strength of many encryption applications and cryptosystems were measured by

Non-repudiation and auditing, Proof that the sender forwards the message. I...

Proof that the sender forwards the message. It also prohibits the author of the code from falsely denying that he forward the message. This is achieved by record using the exact ti

Network, what is computer network?

what is computer network?

Understanding a business model of a spammer, The first and foremost need of...

The first and foremost need of  any business is a role to perform for its client base, and for the spammer this will typically be the role of advertising products which, due to the

Ring topology, RING TOPOLOGY In this topology of network the devices a...

RING TOPOLOGY In this topology of network the devices are connected to each other in packed loop. In this network first computer passes data packet to the second and then seco

Explain why spreadsheets are so useful, Question: Spreadsheet packages ...

Question: Spreadsheet packages are widely used in Business. a) Explain why spreadsheets are so useful. b) Spreadsheet files are sometimes saved for use by other software

Network-based ids (nids), Network-Based IDS (NIDS) A NIDS resides on com...

Network-Based IDS (NIDS) A NIDS resides on computer or appliance connected to segment of an organization’s network and looks for signs of attacks. While examining packets, a NID

What do you understand by the concept web of trust, Question: a) Name ...

Question: a) Name a method to allow a person to send a confidential email to another person, without risks of a third-party reading the email. Describe briefly the operations

Cost benefit analysis (cba)-information security, Cost Benefit Analysis (CB...

Cost Benefit Analysis (CBA) The common approach for information security controls is economic feasibility of implementation. CBA is begun by evaluating the worth of assets which

Encryption, How safe is the encryption of virtual private networks?

How safe is the encryption of virtual private networks?

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