Questions
Build the subnetting tables for the following data (Classful addressing): IP: 138.134.11.66 Mask:255.255.192.0

Build the subnetting tables for the following data (Classful addressing):

IP: 138.134.11.66 Mask:255.255.192.0

In: Computer Science

Is there any way to do this function //Recursive method to check if two numbers form...

Is there any way to do this function

//Recursive method to check if two numbers form a given number
private static boolean addition(int[] array, int start, int end, int n) {
if(start < end) {
if (array[start] + array[end] == n) {
return true;
}
if (array[start] + array[end] > n) {
return addition(array, start, end-1, n);
}
if (array[start] + array[end] < n) {
return addition(array, start+1, end, n);
}
}
return false;
}

In: Computer Science

Briefly explain the concept of policing with emphasis on the “leaky bucket” mechanism.

Briefly explain the concept of policing with emphasis on the “leaky bucket” mechanism.

In: Computer Science

Please describe this( Encryption technique -abstract and introduction) below Research paper in your Word ​Abstract In...

Please describe this( Encryption technique -abstract and introduction) below Research paper in your Word

​Abstract

In network communication system, exchange of data mostly occurs on networked computers and devices, mobile phones and other internet based smart electronic gadgets. Importance of network security is increasing day by day for various network and software applications in human life. Many of the human activities are automatic and in future more areas will come as part of networking system. So most of the end-devices will come to the internet and connect, it is important to ensure the security of data being transmitted. The data and network encryption algorithms play a huge role to ensure the security of data in transmission. In this paper, we provide a theoretical overview of various encryption techniques, namely those that range from changes in the position of a letter or word to word transformations and transposition. These not only provide security when sending messages, but also security for passwords that are used to decipher and to encrypt. The conclusions in this study examine the current theoretical framework,
and propose the usage of methods to prevent online security breaches

​ Introduction
Encryption simply means the translation of data blocks into a secret code which is considered the most effective way to ensure data security. To read a secret file one must have access to a secret key that enables to decrypt it. Unsecured data where no encryption algorithms were used travels through different networks are open to many types of attacks and can be read, changed or forged by any attacker who has access to that data or network. To prevent such attacks encryption and decryption techniques are employed. Encryption algorithms are used by many software and network applications, but most of them are not free from cyber-attacks. Now a days encryption techniques uses algorithms with a “key” to encrypt data into digital secret code and then decrypting it by restoring it to its original data. It is important to protect things like biometric information, email data, medical records, corporate information, personal data, legal documents, transactions details from unauthorized access. Encryption techniques uses a fixed length parameter or key for data transformation. There are mainly two types of algorithms used to encrypt data, asymmetric encryption and symmetric encryption. Many research and analysis of different encryption algorithms such as DES, 3DES, AES, Blowfish, Twofish, Serpent, RC2, RC5, are going on which helps to identify the pros and cons of algorithms in various platforms and application areas. Today's most widely used encryption algorithms fall into two categories: symmetric and asymmetric. Symmetric-key ciphers, also referred to as "secret key," use a single key, sometimes referred to as a shared secret because the system doing the encryption must share it with any entity it intends to be able to decrypt the encrypted data. The most widely used symmetric-key cipher is the ​Advanced Encryption Standard (AES​), which was designed to protect government classified information.
Symmetric-key ​encryption is usually much faster than asymmetric encryption, but the sender must exchange the key used to encrypt the data with the recipient before the recipient can perform decryption on the cipher text. The need to securely distribute and manage large numbers of keys means most cryptographic processes use a symmetric algorithm to efficiently encrypt data, but they use an asymmetric algorithm to securely exchange the secret key. All securely transmitted live traffic today is encrypted using symmetric encryption algorithms for example such as live telephone conversation, streaming video transmission, high speed data link. Blowfish, AES, RC4,DES, RC5, and RC6 are examples of symmetric encryption. The most widely used symmetric algorithm is AES-128, AES-192, and AES-256. In asymmetric​ key encryption, different keys are used for encrypting and decrypting a message. Asymmetric cryptography, also known as public key cryptography, uses two different but mathematically linked keys, one public and one private. The public key can be shared with everyone, whereas the private key must be kept secret. The RSA encryption algorithm is the most widely used public key algorithm, partly because both the public and the private keys can encrypt a message; the opposite key from the one used to encrypt a message is used to decrypt it. This Attribute provides a method of assuring not only confidentiality, but also the integrity, authenticity and non reputability of electronic communications and data at rest through the use of digital signatures. Diffie-Hellman, RSA, ECC, ElGamal, DSA. The following are the major asymmetric encryption algorithms used for encrypting or digitally signing data.

In: Computer Science

Question 1. Present the Use Case and Activity diagram which represents the admission process of a...

Question 1.

Present the Use Case and Activity diagram which represents the admission process of a student in a particular course in the B University.                      [20 Marks]

1 .Use case diagram                         

2.Activity diagram                           

Question.2

A Person who is seeking a job in a company about to apply through online mode. Draw the Class diagram and Sequence diagram for the said scenario.                                                      [20 Marks]

  1. Class diagram                                
  2. Sequence diagram                         

QUESTION 3

You have been appointed as Manager of a software company. Your organisation uses various models for developing a project. If the company gets a Big-scale project from a Client, Which specific model will you choose and why?                                                                      [15 Marks]

  1. Choosing of the Process model                            
  2. Reasons                                                                       

In: Computer Science

Please do this in PSEUDOCODE.Give a baby $5,000! Did you know that, over the last century,...

Please do this in PSEUDOCODE.Give a baby $5,000! Did you know that, over the last century, the stock market has returned an average of 10%? You may not care, but you’d better pay attention to this one. If you were to give a newborn baby $5000, put that money in the stock market and NOT add any additional money per year, that money would grow to over $2.9 million by the time that baby is ready for retirement (67 years)! Don’t believe us? Check out the compound interest calculator from MoneyChimp and plug in the numbers! To keep things simple, we’ll calculate interest in a simple way. You take the original amount (called the principle) and add back in a percentage rate of growth (called the interest rate) at the end of the year. For example, if we had $1,000 as our principle and had a 10% rate of growth, the next year we would have $1,100. The year after that, we would have $1,210 (or $1,100 plus 10% of $1,100). However, we usually add in additional money each year which, for simplicity, is included before calculating the interest. Your task is to design (pseudocode) and implement (source) for a program that 1) reads in the principle, additional annual money, years to grow, and interest rate from the user, and 2) print out how much money they have each year. Task 3: think about when you earn the most money! Lesson learned: whether it’s your code or your money, save early and save often… Sample run 1: Enter the principle: 2000 Enter the annual addition: 300 Enter the number of years to grow: 10 Enter the interest rate as a percentage: 10 Year 0: $2000 Year 1: $2530 Year 2: $3113 Year 3: $3754.3 Year 4: $4459.73 Year 5: $5235.7 Year 6: $6089.27 Year 7: $7028.2 Year 8: $8061.02 Year 9: $9197.12 Year 10: $10446.8

In: Computer Science

Part 2: An electric company charges to their customers based on Kilowatt-Hours (Kwh) used. The rules...

Part 2: An electric company charges to their customers based on Kilowatt-Hours (Kwh) used. The rules to compute the charge are: First 100 Kwh, 35 cents per Kwh Each of the next 100 Kwh (up to 200 Kwh), 45 cents per Kwh (the first 100 Kwh used is still charged at 35 cents each) Each of the next 300 Kwh (up to 500 Kwh) 65 cents per Kwh All Kwh over 500, 80 cents per KH Create a C# Form with a textbox to enter Kwh used, a read-only textbox to display the electricity charges, and a button to compute the charges. The Kwh used could be a number with decimals. Requirements: 1. Input validation: Use the KWH textbox validating event to ensure the KWH cannot exceed 2000. Test your program with (1) Kwh=4500, (2) Kwh = 350 2. Turn in the form’s screenshot and the code.

In C# using Visual Studios 2017 Windows form app

In: Computer Science

public class Account{ public int bal; // this store the balance amount in the account public...

public class Account{

public int bal; // this store the balance amount in the account

public Account(int initialBalance)

{

bal = initialBalance;

}

public static void swap_1(int num1, int num2)

{

int temp = num1;

num1 = num2;

num2 = temp;

}

public static void swap_2(Account acc1, Account acc2)

{

int temp = acc1.bal;

acc1.bal = acc2.bal;

acc2.bal = temp;

}

public static void swap_3(Account acc1, Account acc2)

{

Account temp = acc1;

acc1 = acc2;

acc2 = temp;

}

}

Now, different students tried to use different swap_*() methods to swap the balances in their friends’ bank accounts. Predict the output of each of the following code snippets [1 pts each]

(a) Account tom = new Account(100);

Account jim = new Account(2000);

System.out.println(“1.Tom has $” + tom.bal + “Jim has $” + jim.bal);

swap_1(tom.bal, jim.bal);

System.out.println(“2.Tom has $” + tom.bal + “Jim has $” + jim.bal);



(b) Account tom = new Account(100);

Account jim = new Account(2000);

System.out.println(“1.Tom has $” + tom.bal + “Jim has $” + jim.bal);

swap_2(tom, jim);

System.out.println(“2.Tom has $” + tom.bal + “Jim has $” + jim.bal);



(c) Account tom = new Account(100);

Account jim = new Account(2000);

System.out.println(“1.Tom has $” + tom.bal + “Jim has $” + jim.bal);

swap_3(tom, jim);

System.out.println(“2.Tom has $” + tom.bal + “Jim has $” + jim.bal);




Section B: Fun with stacks [2 pts each question]

Consider a generic Stack class implemented using linked list with the following methods:

  • public boolean isEmpty(), which returns true if and only if the stack is empty;

  • public T pop() throws StackUnderflowException, which removes and returns the top element of the stack (if the stack is empty, it throws StackUnderflowException);

  • public T peek() throws StackUnderflowException, which returns the top element of the stack (but does not remove it; it throws exception if stack is empty);

  • public void push(T element), which pushes an element onto the stack

Predict the output of each of the following code snippets

(a) Stack<Integer> s = new Stack<Integer>();

try{

s.push(5);

s.push(10);

System.out.println(s.peek());

System.out.println(s.pop());

s.push(20);

System.out.println(s.pop());

}
catch(Exception e) { System.out.print(“An exception was thrown”); }





(b) Stack<Integer> s = new Stack<Integer>();

try{

s.push(5);

s.push(50);

System.out.println(s.pop());

System.out.println(s.pop());

System.out.println(s.peek());

s.push(30);

}
catch(Exception e) { System.out.println(“An exception was thrown”); }





(c) Stack<Integer> s = new Stack<Integer>();

try{

s.push(5);

System.out.println(s.pop());

System.out.println(s.isEmpty());

s.push(10);

s.push(43);

s.push(s.pop());

System.out.println(s.peek());

} catch(Exception e) {

System.out.println(“An exception was thrown”);

}





(d) Stack<Integer> s = new Stack<Integer>();

try {

s.push(5);

s.push(10);

while(!s.isEmpty())

{

System.out.println(s.peek());

}

}
catch(Exception e) { System.out.println(“An exception was thrown”); }






Section C: Implementing Stack using Linked List

In this section, you will implement a generic Stack class implemented using linked list. Assume the linked list node class is already defined as below:
public class LLNode<T> {
public LLNode<T> link;

public T info;

public LLNode(T in) { info = in; link = null; }

}

Note that both class variables are public so any outside class can access them directly. Also assume that class StackUnderflowException has been defined that inherits Java’s Exception class. Your task is to implement four methods in the generic class LinkedListStack<T>.

public class LinkedListStack<T> {

private LLNode<T> head; // head of linked list, also stack top pointer

public LinkedListStack() { head = null; } // constructor

public boolean isEmpty() { // [1 pts]

// TODO: return true if stack is empty, false otherwise

// NO MORE THAN 1 LINE OF CODE!

}

public void push(T element) { // [2 pts]

// TODO: push an element to the stack

// NO MORE THAN 3 LINES of CODE!

}

public T peek() throws StackUnderflowException { // [2 pts]

// TODO: return the top element of the stack (but do NOT
// remove it). NO MORE THAN 4 LINES of CODE!

}

public T pop() throws StackUnderflowException { // [3 pts]

// TODO: remove and return the top element of the stack

// It throws StackUnderflowException if stack is empty

// NO MORE THAN 6 LINES of CODE!

}

In: Computer Science

The Active Directory (AD) domain name is the same as the DNS name. True False 2...

  1. The Active Directory (AD) domain name is the same as the DNS name.

    True

    False

2 points   

QUESTION 32

  1. _________ provides the following management services:

    • Detect, isolate, diagnose, and correct problems
    • Report status to end users and managers
    • Track trends related to problems

    Fault management

    Configuration management

    Accounting management

    Performance management

2 points   

QUESTION 33

  1. The _______ layer can include routers, switches, bridges, shared-media hubs, and wireless APs.

    core

    user

    distribution

    access

In: Computer Science

We learned that when calling subprograms or functions that we can pass data to the subprogram...

We learned that when calling subprograms or functions that we can pass data to the subprogram or function by ‘value’ or by ‘reference’. Describe what each approach is, how it works and what the potential security disadvantage is when passing parameters by reference.

In: Computer Science

The credit plan at TidBit Computer Store specifies a 10% down payment and an annual interest...

The credit plan at TidBit Computer Store specifies a 10% down payment and an annual interest rate of 12%. Monthly payments are 5% of the listed purchase price, minus the down payment.

Write a program that takes the purchase price as input. The program should display a table, with appropriate headers, of a payment schedule for the lifetime of the loan. Each row of the table should contain the following items: The month number (beginning with 1) The current total balance owed The interest owed for that month

The amount of principal owed for that month The payment for that month The balance remaining after payment

The amount of interest for a month is equal to balance × rate / 12. The amount of principal for a month is equal to the monthly payment minus the interest owed.

I am using Python.

In: Computer Science

THIS IS ALL ON PYTHON Recursion Practice Recall from lecture that a recursive function is one...

THIS IS ALL ON PYTHON

Recursion Practice

Recall from lecture that a recursive function is one that calls on itself. Recursive functions have two parts, the base case which stops the recursion and the recursive step where the function calls upon itself.

When designing recursive algorithms, your goal for each step should be to work towards the base case. More abstractly, each recursive call decreases the size of the problem, working ever closer to some trivial case with a defined solution.

uppercount(s)

Write a recursive function uppercount(s) that counts a number of uppercase letters in the input string. Do not use loops or built-in Python string functions (the only string functions you can use are slicing and indexing).

>>>> n = uppercount("Hello, World")
print(n)
2

Add comments to your code to point out the base case and the recursive case.

clean_string(s)

From the standpoint of Python, words like ”world” and ”world!” as different words. So if we wrote an automatic English-to-Spanish translator that replaced ”world” with ”mundo”, ”world” would have been replaced and ”world!” wouln’t. I.e. we notice that before we can write a program for automatic translation, we need to find a way to ignore punctuation in a string. Write a recursive function clean_string(s) that would remove all symbols that are not uppercase or lowercase letters or space from s and return the ”clean” string.

Do not use loops.

>>>> CS = clean_string("Hello, world") print(CS)
Hello world

Add comments to your code to point out the base case and the recursive case.

clean_list(lst1, lst2)

Using a similar idea to the one you employed in clean string(s) function, write a recursive function clean_list(l1, l2) that takes two lists as input and returns a list of elements from lst1 that are not present in lst2.

Do not use loops.

>>>> unique = clean_list([1,2,3,4,5,6,7], [2,4,6]) print(unique)
[1,3,5,7]

Add comments to your code to point out the base case and the recursive case.

Recursions vs. Iteration

As we discussed, recursion is a very powerful problem-solving technique. In fact, any computation can be expressed recursively. However, recursion doesn’t always lead to efficient solution, as you will now see. A classic example of recursion is the definition of Fibonacci number.

Wikipedia has a good article about it: Fibonacci Number. (Remember to check the part that talks about Fibonacci numbers in nature).

A Fibonacci number is defined as follows:

F(0) = 0
F(1) = 1
F(n) = F(n−1) + F(n−2) for n > 1.

Recursive Fibonacci

Write a recursive function F(n) that returns n-th Fibonacci number. In comments, mark the base case and recursive step.

Iterative Fibonacci

Write an iterative function (using iteration, i.e. loop(s)) f(n) that returns n-th Fibonacci number.

In: Computer Science

Suppose that our 9-member MIPS core instruction subset is to be augmented to include the addiu...

Suppose that our 9-member MIPS core instruction subset is to be augmented to include the addiu instruction. Explain how just the control bits generated by the control unit must be expanded or modified to allow the addiu instruction to be executed on the single-cycle datapath. Indicate the proper setting for each of the bits generated by the control unit for an addiu instruction

In: Computer Science

I NEED TO DEBUG THIS PSUEDOCODE // This pseudocode should determine and output the rental fees...

I NEED TO DEBUG THIS PSUEDOCODE

// This pseudocode should determine and output the rental fees for cars.
// Standard cars rent for $65 per day, compacts rent for $40 per day,
// and subcompacts rent for $30 per day. Rentals for at least 7 days
// receive a 20% discount. An error message is displayed if the car type
// is not valid.

start
Declarations
string carType
num days
num STD_RATE = 65
num COM_RATE = 40
num SUB_RATE = 30
num DAYS_FOR_DISCOUNT = 10
num DISCOUNT_RATE = 0.20
string QUIT = "ZZZZ"
getReady()
while carType <> QUIT
detailLoop()
endwhile
finish()
stop

getReady()
output Enter car type or , QUIT, to quit
input carType
return

detailLoop()
output "Enter days rented "
input days
if carType = "Standard" then
rate = STD_RATE
else
if car_Type = "Compact" then
rate = COMPACT_RATE
else
if carType = "Subcompact" then
rate = SUB_RATE
else
rate = 0
output "Invalid car type"
endif
endif
endif
if rate <> 0
if days >= DAYS_FOR_DISCOUNT then
rate = rate * DISCOUNT_RATE
endif
output carType, days
output "Enter car type or ", QUIT, " to quit "
input carType
return

finish()
output "End of program"
return

In: Computer Science

Draw a Venn diagram for 4 rectangles with all sides vertical or horizontal.

Draw a Venn diagram for 4 rectangles with all sides vertical or horizontal.

In: Computer Science