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

Area subdivision, the advantages and disadvantages of area subdivision and ...

the advantages and disadvantages of area subdivision and where it is applicable

What you understand by the term brute force attack, Question: a) Expla...

Question: a) Explain what you understand by the term brute force attack, giving an example of such an attack b) Briefly outline the concept of Caesar cipher and identify a

Software vulnerabilities, 1.  We used the National Vulnerability Database. ...

1.  We used the National Vulnerability Database. Select a recent vulnerability from that Database and analyse it from the following aspects: Criticality level Impact in

Elliptic curve encryption - decryption scheme, (a) (i) If m = p·q·r where...

(a) (i) If m = p·q·r where p, q, and r are prime numbers, what is Φ(m)? (ii) Therefore, Determine Φ(440). (b) Describe the following terms as used in cryptography: (i)

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

Discuss the importance of ontologies in agent communication, Question 1...

Question 1 The speech act theory is used as the model for communication among computational agents. Locution, illocution, and perlocution are the 3 aspects of this theory Using

Placeholders for the plaintext characters, Encode the following plaintext, ...

Encode the following plaintext, using the Caesar cipher:             LORD OF THE RINGS b) The following ciphertext              jw njbh lxmn cx kanjt has been encoded usi

Why is this setup not secure, Question: a) You are using Active Directo...

Question: a) You are using Active Directory Users under Windows Server 2003 and Computers to configure user objects in your domain, and you are able to change the address and

Deploying host-based idss, Deploying Host-Based IDSs -Proper implementat...

Deploying Host-Based IDSs -Proper implementation of HIDSs can be painstaking and time-consuming task .The process of deployment begins with implementing most critical systems fi

Wireless local area network, a) Wireless local area network (WLAN) technol...

a) Wireless local area network (WLAN) technologies constitute a fast-growing market introducing the flexibility of wireless access into office, home, or production environments. G

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