Cryptography, Computer Engineering

Assignment Help:

Basically I need implement program using LC3 assembly language where I can type any message using ASCII code (this will my input). Then read the output in cipher text. It has to be a combination of this to labs in the bottom. ( please make sure design the flow chart for the program)

Computer Organization and Architecture Lab 4: Cryptography

Description:

An encryption algorithm transforms "plain text" into "cipher text." Just like a door needs a key to lock and unlock it, an encryption algorithm often requires a key to encrypt and decrypt a message. For example, suppose the plain text message is HELLO WORLD. An encryption algorithm consisting of nothing more than replacing each letter with the next letter in the alphabet would produce the cipher text IFMMP XPSME. The decryption algorithm simply replaces each letter with the one before it, and presto: the plain text HELLO WORLD is produced.
Procedure:

Implement, in LC-3 assembly language, an encryption/decryption program that meets the following requirements:
1. The key is 6 and stored at x31 00.
2. Your message is restricted to a maximum of 32 characters. They are stored at x3110 to x311 F. The last ASCII code of the text string must be EOT (x04).
3. The encryption algorithm is as follows. Each ASCII code in the message will be transformed as follows:
• The low order bit (LSB) of the code will be toggled. That is, if it is a 1, it will be replaced by 0 and vice verse.
• The key will be added to the result of step 1 above.
• The result should be stored at location x3120 to x312F.
• For example, if the input (plain text) is A and the encryption key is 6, the program should take the ASCII value of A, 01000001, toggle bit [3:0], producing 01001110 and then add the encryption key, 6. The final output character would be 01000110, which is the ASCII value F.
4. Decryption algorithm is as follows. Each ASCII code in the message will be transformed as follows:
• Subtract the encryption key from the ASCII code.
• Toggle the low order bit of the result of ste

• The result should be stored back to location x311 0 to x311 F.
Notes and Suggestions:
• The first line of your programs must specify the memory address of the first instruction of your program. LC-3 simulator will place your program starting at that address. For this assignment, you should place your program starting at x3000 (using the .ORIG pseudo¬op) .
• If you are using a Windows machine, use the LC3Edit program to type in your programs.
On Sun and Linux workstations, pico, emacs, and vi are several of the text editors you can use. Your program file needs to be in plain text format.


Related Discussions:- Cryptography

Explain the design reusability of verilog, Explain the Design reusability o...

Explain the Design reusability of Verilog There is no concept of packages in Verilog. Functions and procedures used within a model should be  defined  in  the  module.  To  mak

What is .net and .net framework, What is .NET / .NET Framework?  It is ...

What is .NET / .NET Framework?  It is a Framework in which Windows applications might be developed and run. The Microsoft .NET Framework is a platform for building, deploying,

Health care professional, Overall, Mr. X is an intelligent and high-functio...

Overall, Mr. X is an intelligent and high-functioning man with good psychological, social, and occupational functioning. The test battery did not reveal any difficulties that warra

Can you list out some of enhancements in verilog 2001, Can you list out som...

Can you list out some of enhancements in Verilog 2001? In  earlier  version  of  Verilog,  we  use  'or'  to  specify  more  than  one  element  in  sensitivity  list.  In Veri

Weka uses a gaussian - radial basis function, A data set with 1000 rows is ...

A data set with 1000 rows is input to a neural network in Weka. The test option is set to 10-fold cross validation and the neural network option validationSetSize = 20%. How many r

Mini project, give proper code for any kind of project in oop c++

give proper code for any kind of project in oop c++

Explain the working of master-slave JK flip flop, With relevant diagram exp...

With relevant diagram explain the working of master-slave JK flip flop. Ans. Master-Slave J-K FLIP-FLOP: A cascade of two S-R FLIP-FLOPS is a master-slave J-K FLIP-FLOP. One

The first digit of a decimal constant, The first digit of a decimal constan...

The first digit of a decimal constant must be Decimal constants having of a set of digit, 0 to 9, preceded by an optional - or + sign.

Design tables in html, In this portion you would see how to put tables in y...

In this portion you would see how to put tables in your web documents. It isn't that a table is simply a combination of rows and columns. If you have ever seen any table in an attr

Execution of micro-program, The micro-instruction cycle can comprises two b...

The micro-instruction cycle can comprises two basic cycles: the fetch and execute. Here in the fetch cycle address of micro-instruction is produced and this micro-instruction is pu

Write Your Message!

Captcha
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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd