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

Estimate the average throughput, Question (a) Estimate the average thr...

Question (a) Estimate the average throughput between two hosts given that the RTT for a 100 bytes ICMP request-reply is 1 millisecond and that for a 1500 bytes is 2 millisecon

Ip address, How to find an ip address?

How to find an ip address?

Documenting the results of risk assessment, Documenting the Results of Risk...

Documenting the Results of Risk Assessment The goal of this process is to recognize the information assets, list them, and rank according to those most required protection. The

Explain how inter-vlan communication, QUESTION a) A switch basically ...

QUESTION a) A switch basically operates by forwarding frames from one part of the network to another, based on MAC address. Describe the three types of switching namely store

Arrangement of self-learning switches, QUESTION a) Consider the speed ...

QUESTION a) Consider the speed of propagation of an electrical signal is same to 2x10 8 m/s, evaluate the ratio of the propagation delay to the transmit time for the given typ

Representation of a tcp header, (a) Figure is a representation of a TCP hea...

(a) Figure is a representation of a TCP header. For each of the fields lettered from A to G, state the name of the field and provide a brief explanation for the function of each fi

#title.TIPS., 1. For this project, assume that an organization has five ser...

1. For this project, assume that an organization has five servers. Server 1 has a TCO of $25,000, Servers 2 and 3 have a TCO of $37,000 each, and the remaining two servers— Servers

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

Arp responses, ARP RESPONSES Let's search out how does a computer know...

ARP RESPONSES Let's search out how does a computer know whether an incoming frame have an ARP message. The type field in the frame header defines that the frame contain an ARP

Describe how ethernet deals with collisions, Problem (a) The IEEE 802 seri...

Problem (a) The IEEE 802 series of standards describe both the Physical and Data Link layers of their respective technologies. Two important standards are 802.3 and 802.5, respect

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