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

Location to e-mail messages are saved, In the e-mail system, where the e-ma...

In the e-mail system, where the e-mail messages are saved and why? E-mail messages are saved in user’s private electronic mailbox. A mailbox refers to a local/domestic hard drive c

Risk control strategies-, Risk Control Strategies Once the ranked vulner...

Risk Control Strategies Once the ranked vulnerability risk worksheet has created, they should choose one of following 4 strategies to control each risk: •Apply safeguards which

Explain the operation of the matchmaker middle agent, Question 1: (a) E...

Question 1: (a) Explain the operation of the "matchmaker" middle agent. (b) Describe why broker middle agents are more efficient in terms of the time taken for a service to

Define full-duplex., A  full-duplex (FDX) , accepts communication in both...

A  full-duplex (FDX) , accepts communication in both ways, and, unlike half-duplex, accept this to occur simultaneously. Land-line telephone networks are full-duplex, since they

What is network virtual terminal, Network Virtual Terminal It is a set...

Network Virtual Terminal It is a set of principles describing a very simple virtual terminal interaction. The NVT is needed in the start of a Telnet session. Communication wit

Log file monitors-information security, LOG FILE MONITORS Log file monit...

LOG FILE MONITORS Log file monitor (LFM) is similar to NIDS. It reviews log files generated by servers, network devices, and even other IDSs for patterns and signatures. Pattern

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

How safe is the encryption of virtual private networks?

Describe how access control is implemented, Question: (a) How can you ...

Question: (a) How can you prevent someone from accessing your computer when you leave your office for some time? (b) What is the difference between a classic login and a w

Miss, You are an IT Security administrator in a banking organization. Your ...

You are an IT Security administrator in a banking organization. Your organization hired an outside IT firm to do a proof of Concept for new equipment which is a computer based syst

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

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