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

Explain the security service - confidentiality, Question: (a) Explain t...

Question: (a) Explain the following security services: Confidentiality, Availability. (b) Which attack will be used to bypass even the best physical and logical security m

Keystroke-based access control model, Suppose you are working for one of th...

Suppose you are working for one of the leading credit reporting agencies that manages users' credit rating info with different financial institutions.  The company wishes to implem

Nessus vulnerability, You see two IP addresses. The IP address 192.168.58.1...

You see two IP addresses. The IP address 192.168.58.130 is the one of Bt4. The IP address 192.168.58.133 has ports 135 and 445 open; which indicates that it is a Windows machine. S

Categories of controls-information security, Categories of Controls Cont...

Categories of Controls Controlling risk through mitigation, avoidance or transference is accomplished by implementing controls. There are 4 effective approaches to select the co

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

Internet protocol (ipv6), SUCCESS OF IP:  IP has accommodated dramatic...

SUCCESS OF IP:  IP has accommodated dramatic modification since real design. But basic rules are still appropriate today. There are many new kinds of hardware. SCALING:

Important features of application layer, Describe the important features of...

Describe the important features of application layer. The features of the application layer are as follows. 1. Efficient User Interface Design is explained below: Appli

Computer Security, I have an assignment of Computer Security to submit. Wil...

I have an assignment of Computer Security to submit. Will you guys help me making my assignment???

Configure a router from command line interface, QUESTION (a) Describe ...

QUESTION (a) Describe the difference between static routing and dynamic routing algorithms. (b) List four functions that are performed by the Cisco IOS software during b

Base lining-risk management, Base lining •    Organizations do not have ...

Base lining •    Organizations do not have any contact to each other •    No two organizations are identical to each other •    The best practices are a moving target •    K

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