Explanation:
For the Class B address 172.16.0.0:
What is the default subnet mask of a Class B IPv4 address?
255.255.0.0
What is the first usable IP address of this “not-subnetted” network?
172.16.0.1
What is the last usable IP address of this “not-subnetted” network?
172.16.255.254
What is the broadcast address of this “not-subnetted” network?
172.16.255.255
How many total hosts are allowed on this “not-subnetted” network?
65,534
Let’s split this network into 4 subnets
What is the new subnet mask?
255.255.192.0
What is the first subnet address of your newly subnetted address?
172.16.0.0
What is the first usable IP address of your newly subnetted address?
172.16.0.1
What is the last usable IP address of your newly subnetted address?
172.16.63.254
What is the broadcast address of your newly subnetted address?
172.16.63.255
How many usable hosts are on this subnet?
16,382
For the second subnet:
Network (subnet) address: 172.16.64.0
Usable host range: 172.16.64.1 - 172.16.127.254
Broadcast: 172.16.127.255
For the third subnet:
Network (subnet) address: 172.16.128.0
Usable host range: 172.16.128.1 - 172.16.191.254
Broadcast: 172.16.191.255
For the fourth subnet:
Network (subnet) address: 172.16.192.0
Usable host range: 172.16.192.1 - 172.16.255.254
Broadcast: 172.16.255.255
The following information for the second, third, and fourth new subnets are:
Second subnet:
Network (subnet) address: 172.16.64.0
Usable host range: 172.16.64.1 - 172.16.127.254
Broadcast: 172.16.127.255
What is subnets?Subnets are a way of dividing a computer network into separate, smaller networks. It allows an organization to create multiple logical networks within a single physical network. Subnets allow for better security, control, and performance. Each subnet has its own network address and a range of IP addresses that can be used for hosts. All hosts within a subnet can communicate directly with each other without the need for a router. Subnets also allow organizations to segment their network into different levels of access and security. This helps to prevent unauthorized access to sensitive information or resources.
Third subnet:
Network (subnet) address: 172.16.128.0
Usable host range: 172.16.128.1 - 172.16.191.254
Broadcast: 172.16.191.255
Fourth subnet:
Network (subnet) address: 172.16.192.0
Usable host range: 172.16.192.1 - 172.16.255.254
Broadcast: 172.16.255.255
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You suspect a problem with a file that is important to one of your installed applications. You are running Windows 7 64-bit edition. You have thoroughly checked the Program Files folder and cannot find the folder that holds this application. What might be the problem?
Answer:
Explanation:
There could be a few potential problems that could be causing the issue:
The application might not have been installed correctly, and the files are located somewhere else on the computer. In this case, you may need to search the entire computer or contact the application's support team for assistance.
The application may have been uninstalled, or the files could have been deleted or moved. If this is the case, you may need to reinstall the application or restore the files from a backup.
The application might not be compatible with Windows 7 64-bit edition, and therefore, the files may not be stored in the Program Files folder. In this case, you may need to check the application's documentation or contact the support team to determine where the files are located.
Overall, it is essential to troubleshoot the issue thoroughly and gather as much information as possible to determine the root cause of the problem.
When designing a data backup and recovery plan, what’s the first thing to figure out
The first step in developing a data backup and recovery plan is determining what data needs to be backed up and how regularly. This entails determining the crucial systems and data.
What factors should you take into account while choosing backup and recovery procedures?The physical aspects of carrying out the task, the requirement for backup, operational features, and the security and integrity of the backup media must all be taken into account when selecting backup and recovery solutions.
What component of a data backup solution is crucial?To safeguard against primary data loss or corruption, it is essential to save a copy of the data on a different medium. An external drive is a straightforward example of an additional medium.
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Types of Selective Enforcement?
Answer:
In law, selective enforcement occurs when government officials (such as police officers, prosecutors, or regulators) exercise discretion, which is the power to choose whether or how to punish a person who has violated the law. The biased use of enforcement discretion, such as that based on racial prejudice or corruption, is usually considered a legal abuse and a threat to the rule of law.
In some cases, selective enforcement may be desirable.[1] For example, a verbal warning to a teenager may effectively alter their behavior without resorting to legal punishment and with the added benefit of reducing governmental legal costs. In other cases, selective enforcement may be inevitable. For example, it may be impractical for police officers to issue traffic tickets to every driver they observe exceeding the speed limit, so they may have no choice but to limit action to the most flagrant examples of reckless driving. Therefore, the mere fact that a law is selectively enforced against one person and not against another, absent bias or pattern of enforcement against a constitutionally-protected class, is not illegal.
Assignment 4: Divisible by Three need help pls pls plsss
Divisibility by three is a basic concept in arithmetic that is important to understand for various mathematical operations.
In order to determine if a number is divisible by three, you can use the rule of threes: add up the digits of the number and if the sum is divisible by three, then the original number is also divisible by three.For example, let's consider the number 453. We add the digits together: 4 + 5 + 3 = 12. Since 12 is divisible by three, we know that 453 is also divisible by three.This rule works for larger numbers as well. For instance, consider the number 6,201. Adding the digits gives us: 6 + 2 + 0 + 1 = 9. Since 9 is divisible by three, we can conclude that 6,201 is also divisible by three.Understanding the concept of divisibility by three is important for various mathematical operations such as long division, fractions, and even algebra.
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A program is required to compute the cost of a car trip. The required input values are:
Litres per 100km
Distance travelled
Cost per litre of petrol
The output value is the total cost of the trip.
The program required to compute the above in Phyton is given below.
What is the program that computes the cost of a car trip using the above parameters?the required program is given as follows;
# Input values
litres_per_100km = float(input("Enter the fuel efficiency of your car in litres per 100km: "))
distance_travelled = float(input("Enter the distance travelled in km: "))
cost_per_litre = float(input("Enter the cost per litre of petrol in your local currency: "))
# Calculate the total litres of petrol used
litres_used = (litres_per_100km / 100) * distance_travelled
# Calculate the total cost of the trip
total_cost = litres_used * cost_per_litre
# Display the result
print(f"The total cost of the trip is {total_cost:.2f} {currency_symbol}")
Note that this program prompts the user to enter the fuel efficiency of their car in litres per 100km, the distance travelled in km, and the cost per litre of petrol in their local currency.
It then calculates the total litres of petrol used by multiplying the fuel efficiency by the distance travelled, and calculates the total cost of the trip by multiplying the litres used by the cost per litre.
Finally, it displays the result to the user, rounded to two decimal places. Note that the currency symbol can be added to the output string depending on the user's location.
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Arithmetic Instructions: Activity : Display 3 Digits (Assembly Code)
Hardcode a 3 digit value into a variable. Display the number
The value 123 is hardcoded into the "number" variable that is defined in this code. The programme then prepares the output by changing the value of "number" and initialising the registers with the proper values.
How many arithmetic instructions are there in three?Binary, decimal, logical, shift/rotate, and bit/byte manipulation instructions are additional categories for the arithmetic instructions.
section .data
number db 123 ; hardcode the 3-digit value
section .text
global _start
_start:
; set up the output
mov eax, 4 ; use the write system call
mov ebx, 1 ; write to standard output
mov ecx, number ; move the number variable into ecx
mov edx, 3 ; print 3 characters
; display the number
int 0x80 ; execute the system call
; exit the program
mov eax, 1 ; use the exit system call
xor ebx, ebx ; return 0 to indicate success
int 0x80 ; execute the system call
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Shifts in production possibilities Suppose the fictional country of Yosemite produces two types of goods: agricultural and capital. The following diagram shows its current production possibilities frontier for sorghum, an agricultural good, and microprocessors, a capital good. Drag the production possibilities frontier (PPF) on the graph to show the effects of a breakout of avian flu that sickens millions of workers. Note: Select either end of the curve on the graph to make the endpoints appear. Then drag one or both endpoints to the desired position. Points will snap into position, so if you try to move a point and it snaps back to its original position, just drag it a little farther.
The drag the production possibilities frontier (PPF) on the graph to show the effects of a breakout of avian flu that sickens millions of workers would shift the PPF inwards towards the origin.
What is production possibilities frontier (PPF)?The production possibilities frontier (PPF) is an economic concept that illustrates the maximum amount of output an economy can produce with a given amount of inputs. It is a graphical representation of the combination of two or more products that an economy can produce with the available resources. The PPF depicts the maximum possible production at different levels of inputs and shows the trade-offs between the two products.
This is because the avian flu would reduce the number of workers available to produce the goods, thus reducing the amount of goods that can be produced at any given time.
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1. Which of the following supports a vehicle's weight?
OA. Shock
OB. Idler arm
OC. Stabilizer link
OD. Spring
The component that supports a vehicle's weight is the spring.
What is the Spring?The spring is responsible for absorbing the shock and weight of the vehicle, ensuring a smooth ride for the passengers. The idler arm is part of the steering system, while the stabilizer link helps to control the vehicle's sway and stability during turns.
The shock, on the other hand, helps to dampen the bounce and movement of the vehicle. While all of these components play a vital role in a vehicle's performance, it is ultimately the spring that bears the weight and keeps the vehicle stable on the road.
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Describe the steps of the diagnostic process, including methods and information that are used in the
understand the process methods and information that are used in the diagnostic process as a IT technician.
-information garthing
-information analysis
- solutions identification
As an IT technician, the diagnostic process typically involves the following steps:
Information GatheringInformation AnalysisSolution IdentificationWhat is the diagnostic process?Information Gathering: The first step in the diagnostic process is to gather information from the user who reported the problem. This may involve asking questions about the symptoms they are experiencing, when the problem started, and any recent changes or updates that may have been made to the system.
Information Analysis: Once the information has been gathered, the next step is to analyze it in order to identify possible causes of the problem. This may involve reviewing system logs or error messages, checking system configurations, and running diagnostic tools to gather more information.
Solution Identification: After the information has been analyzed, the next step is to identify possible solutions to the problem. This may involve troubleshooting steps to isolate the cause of the problem or making changes to the system configuration or software settings.
In order to successfully complete the diagnostic process, IT technicians may use a variety of methods and tools, such as:
Remote access tools to connect to the user's system and troubleshoot the problem remotelyDiagnostic software tools to scan for system errors or issuesSystem logs and error messages to identify patterns or commonalities in the reported problemHardware testing tools to identify hardware-related problemsOnline forums and technical resources to search for solutions to similar problems that other users may have experienced.Read more about diagnostic process here:
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Lana wants to start a new query by amending an old one. She should
A.) delete any old criteria.
B.) start the criteria with an asterisk.
C.) start the criteria with a question mark.
D.) add new queries to older ones.
Answer:
delete any old criteria
Describe solid state drive (ssd)
What tool can be used to organize the structure of only the important pages of your website?
You can use a(n)_________ site map to organize the structure of only the important pages of your website.
Answer:
You can use a "visual" site map to organize the structure of only the important pages of your website. A visual site map is a diagram or flowchart that provides an overview of the site's structure, including the main sections, subsections, and important pages. It helps to identify the most important pages and how they are connected, allowing you to prioritize content and ensure that the site is easy to navigate.
Explanation:
can anyone help?
what are the arguments of the function?
Answer choices are
1. Mystery
2. 1
3. 4,8,3
or
4. a,b,c
4, 8, 3 are the arguments of the given code
What are the arguments?Those are the values that are passed into the function and are represented as parameters.
According to the given Javascript code,
The first condition (a < b && b < c) is not true, as 8 is not less than 3.The second condition (b < a && a < c) is not true, as 8 is not less than 4.The third condition (c < a && c < b) is true, as 3 is less than both 4 and 8.If we look at what values are passed in where the function is called. In this case, it gets called in the purple block (console.log). 4, 8, 3 are the arguments of the given code and this is the answer to the given question
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If cell A2 contains "Today is Monday," the result of the function =LEN(A2) would be __________. Fill in the blank space.
Excel Quiz.
If cell A2 includes the phrase "Today is Monday," the result of the function =LEN(A2) would be 15, which is the number of characters in the cell.
How can I figure out how many characters there are in Excel?Type =LEN(cell) in the formula bar and hit Enter to invoke the function. In many instances, cell refers to the cell that you want to count, like B1. Enter the formula, then copy and paste it into further cells to count the characters in each cell.
What does Len have to offer?A number is returned by LEN after it counts the characters in the text, including spaces and punctuation. LEN is set to zero if text is an empty string ("") or a reference to an empty cell.
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Karl has designed an interactive stories website for kids. He has implemented an alphabetical format for browsing through the stories. Which structure will he use for easy navigation?
Karl implements a _________ structure for users to advance through the chapters.
Answer:
Karl implements an alphabetical structure for users to browse through the stories.
Explanation:
Write a program that accepts the name of a group of 5 students and their age one by one. The program will then calculate the average of their ages and will print the result. The program will also print the name and age of the oldest person in the list.
Here's a Python program that accepts the name and age of five students, calculates the average of their ages, and prints the name and age of the oldest student:
# initialize variables
names = []
ages = []
max_age = 0
max_name = ""
# loop to get names and ages
for i in range(5):
name = input("Enter student name: ")
age = int(input("Enter student age: "))
names.append(name)
ages.append(age)
if age > max_age:
max_age = age
max_name = name
# calculate average age
avg_age = sum(ages) / len(ages)
# print results
print("Average age: ", avg_age)
print("Oldest student: ", max_name, max_age)
This program uses a list to store the names and ages of the students. It also keeps track of the maximum age and the corresponding name as it iterates through the input loop. Finally, it calculates the average age and prints out the results.
Answer:
Hey there! I remember based off the last one we needed a beginner friendly version rather than a advanced version! So with that in mind...
names = [None] * 5
ages = [0] * 5
# Collect the names and ages of the 5 students
for i in range(5):
name = input("Please enter the name of student " + str(i + 1) + ": ")
age = int(input("Please enter the age of student " + str(i + 1) + ": "))
names[i] = name
ages[i] = age
# Calculate the average age
average_age = sum(ages) / len(ages)
# Find the oldest student
oldest_age = max(ages)
oldest_index = ages.index(oldest_age)
oldest_name = names[oldest_index]
# Print the results
print("The average age is:", average_age)
print("The oldest student is " + oldest_name + " with an age of " + str(oldest_age))
Explanation:
We create two lists, names and ages, with 5 elements each. The names list is initialized with None values, and the ages list is initialized with 0 values.
Then, we use a for loop to iterate 5 times, as we want to collect information about 5 students. In each iteration, we ask the user to input the name and age of a student.
We use the input() function to get the name of the student and directly assign it to the corresponding index in the names list using names[i] = name.
We use the int() function to convert the user input into an integer (since age is a whole number) and directly assign it to the corresponding index in the ages list using ages[i] = age.
After collecting all the information, we calculate the average age by summing up all the ages in the ages list using the sum() function and dividing it by the number of students (in this case, 5).
To find the oldest student, we first determine the highest age using the max() function, which returns the maximum value in the ages list. Then, we use the index() method to find the index of the oldest age in the ages list. With this index, we can find the corresponding name of the oldest student in the names list.
Finally, we print the average age and the name and age of the oldest student using the print() function.
NOTE: The main difference in this version of the code is that we initialize the lists with a fixed size and assign values directly to each index instead of using the append() method to add elements to the lists.
write a basic program to calculate the area of a circle
Answer: int main() {
float radius, area;
printf("\nEnter the radius of Circle : ");
scanf("%d", &radius);
area = 3.14 * radius * radius;
printf("\nArea of Circle : %f", area);
return (0);
Explanation:
how do you add characters on super smash bros crusade
Answer:
Download the character you want to add as a ".zip" or ".rar" file.
Extract the files from the archive to a folder on your computer.
Open the Super Smash Bros. Crusade folder and locate the "fighters" folder.
In the fighters folder, create a new folder with the name of the character you want to add.
Copy the extracted files from the character archive into the new folder you just created.
Start Super Smash Bros. Crusade and go to the character select screen.
If the character you added is not automatically unlocked, you may need to unlock them by completing certain objectives in the game.
Explanation:
Develop a program that ask for the number of tickets
Answer:
# Ask user for the number of tickets
num_tickets = input("How many tickets would you like to purchase? ")
# Convert the user input to an integer
num_tickets = int(num_tickets)
# Set the price per ticket
PRICE_PER_TICKET = 10
# Calculate the total cost
total_cost = num_tickets * PRICE_PER_TICKET
# Print the number of tickets and total cost to the user
print("You want to purchase " + str(num_tickets) + " tickets, and the total cost is $" + str(total_cost) + ".")
Draw a state process model with two (2) suspend states and fully discuss the
transition of processes from one state to the next by OS.
This process model features two suspend states—Waiting and Suspended—along with three active states—Ready, Running, and Interrupted. There is also a further state known as Zombie.
What two states are there in the two state process model?A two-state model, which has just the two states listed below, is the simplest model for the process state. Currently running state: A state in which the process is active. A process in the "not running" state is one that is awaiting execution.
Suspended process: what is it?The operating system suspends one process by putting it in the Suspended state and moving it to disc if a process in main memory enters the blocked state.
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•Analiza tres anuncios con ofertas de trabajo relacionadas con distintos perfiles profesionales.
Answer:
Explanation:
what language is that?
Which shows the correct order for creating a new column in Datasheet view?
Scroll to the left, select data type, click on Click to Add, and name the field.
O Scroll to the right, select data type, name the field, and click on Click to Add.
Scroll to the left, select data type, name the field, and click on Click to Add
Scroll to the right, click on Click to Add, select data type, and name the field.
Answer:
Scroll to the right, click on Click to Add, select data type, and name the field.
Explanation:
Which aspect of QA ensures that the design complies with the client's requirements?
in________,once the client approves the design list, all detailed layouts and models will be tested against this list
Answer:
inspection
Explanation:
Seva wants to sort several tables in Access but doesn't know how. Which icon should she click on?
A.) the square with the "x"
B.) the overlapping squares
C.) the "abc" with the checkmark
D.) the circle with the question mark
Answer:
C.) the "abc" with the checkmark is the icon to sort tables in Access.
Explanation:
Consider distributing a file of F=15 Gbits to N peers. The server has an upload rate of us=25 Mbps, and each peer has a download rate of di= 5 Mbps and an upload rate of u. For N= 500 and u=12 Mbps, what is the minimum distribution time for N and u for both client-server distribution and P2P distribution
The minimum distributiοn time fοr P2P distributiοn is 2,545 secοnds, which is much faster than client-server distributiοn.
What is the shοrtest distributiοn time fοr N and u fοr bοth client-server and P2P distributiοn?Fοr client-server distributiοn:
The minimum distributiοn time can be calculated as the time it takes fοr the server tο uplοad the entire file tο all N peers:
Time = F / (N * di)
Since N = 500 and di = 5 Mbps = 5/8 MBps, we have:
Time [tex]= 15 * 10^9 / (500 * 5/8 * 10^6) = 7,680[/tex]secοnds
The server can uplοad at a rate οf us = 25 Mbps = 25/8 MBps, which means it can uplοad the entire file in:
Server time[tex]= F / us = 15 * 10^9 / (25/8 * 10^6) = 4,800[/tex]secοnds
Therefοre, the minimum distributiοn time fοr client-server distributiοn is 7,680 secοnds, which is the time it takes fοr all N peers tο dοwnlοad the file.
Fοr P2P distributiοn:
In P2P (peer-tο-peer) distributiοn, each peer can dοwnlοad the file frοm οther peers whο already have parts οf the file. Therefοre, the tοtal uplοad rate is the sum οf the uplοad rates οf all peers:
Tοtal uplοad rate = N * u = 500 * 12 Mbps = 6,000 Mbps
The minimum distributiοn time can be calculated as the time it takes fοr all peers tο receive the entire file. We can use the fοrmula:
Time = F / (tοtal uplοad rate - us)
Since the server's uplοad rate is us = 25 Mbps = 25/8 MBps, we have:
Time [tex]= 15 * 10^9 / (6,000 Mbps - 25 Mbps) = 2,545[/tex] secοnds
Therefοre, the minimum distributiοn time fοr P2P distributiοn is 2,545 secοnds, which is much faster than client-server distributiοn. This is because P2P distributiοn allοws peers tο dοwnlοad the file frοm each οther, which can reduce the lοad οn the server and speed up the distributiοn prοcess.
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Abel is designing a website for a startup IT firm. He intends to discuss the web design with his client. Which tool should Abel use to help his client get a idea of how the website will look?
A. bulleted list of titles, subheadings, and images
B. chart depicting the navigational flow of the website
C. layout of each page with its respective elements
D. pictures and screenshots of websites of other firms
E. programming code for the website
Answer:
c
Explanation:
An international bus touring company has two different ticket prices for its customers when they order online ahead of their departure time or at the gate:
Ticket Price Description:
Plan A: $19.95 per ticket online.
Plan B: $25.95 per ticket at the time of departure.
Plan C: $21.95 per ticket at the time of departure but in a group of 10 or more.
Write a program in Java that calculates a customer’s ticket when they order from all three plans. It should input customer name, mailing address, telephone number, which package the customer has purchased, and how many tickets were purchased.
Input Validation: Be sure the user only selects package A, B, or C. Display screenshots of the user using all three plans.
Answer:
import java.util.Scanner;
public class BusTicketCalculator {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
// Get customer information
System.out.println("Enter customer name:");
String name = input.nextLine();
System.out.println("Enter mailing address:");
String address = input.nextLine();
System.out.println("Enter telephone number:");
String telephone = input.nextLine();
// Get package and number of tickets
System.out.println("Select a package (A, B, or C):");
String packageOption = input.nextLine();
while (!packageOption.equals("A") && !packageOption.equals("B") && !packageOption.equals("C")) {
System.out.println("Invalid package selected. Please choose A, B, or C:");
packageOption = input.nextLine();
}
System.out.println("Enter number of tickets:");
int numTickets = input.nextInt();
// Calculate ticket price based on package and number of tickets
double ticketPrice = 0;
if (packageOption.equals("A")) {
ticketPrice = numTickets * 19.95;
} else if (packageOption.equals("B")) {
ticketPrice = numTickets * 25.95;
} else if (packageOption.equals("C")) {
if (numTickets >= 10) {
ticketPrice = numTickets * 21.95;
} else {
ticketPrice = numTickets * 25.95;
}
}
// Display ticket information
System.out.println("\nTicket Information:");
System.out.println("Name: " + name);
System.out.println("Address: " + address);
System.out.println("Telephone: " + telephone);
System.out.println("Package: " + packageOption);
System.out.println("Number of Tickets: " + numTickets);
System.out.println("Total Price: $" + ticketPrice);
}
}
This took a while as I am not extremely good at coding.
Explanation:
3.1 ldentify TWO possible reasons for unemployment.
Here are two potential causes of unemployment:
Structural unemployment: This happens when job seekers' abilities and available job requirements are not compatible. This can occur when technological advancements make certain positions obsolete or when there is a shift in demand for specific types of work, leaving workers with outdated skills unemployed.Cyclical unemployment: This type of unemployment results from changes in the business cycle, where the economy experiences periods of growth and decline. During recessions or downturns, firms may decrease production and lay off employees to decrease expenses, resulting in an increase in cyclical unemployment.what is the storage of z900 mainframe computer
Assuming you are referring to the IBM System z900 mainframe computer, the storage capacity can vary depending on the specific configuration and options selected.
The z900 uses high-speed storage technologies such as solid-state drives (SSDs) and magnetic disk drives (HDDs) to store data. The system can support various storage configurations, including internal and external storage options.
The internal storage options for the z900 include up to 32GB of main memory (RAM), which is used for active program and data storage during processing. Additionally, the z900 can support up to 136TB of disk storage, which can be divided into multiple logical partitions (LPARs) to provide secure and isolated storage for different applications or users.
Discuss in details the difference among programmed I/O, Interrupt Driven I/O
and Direct Memory access over the processor
Answer:
Programmed I/O, Interrupt Driven I/O, and Direct Memory Access (DMA) are three methods of transferring data between input/output (I/O) devices and the central processing unit (CPU) of a computer system.
Programmed I/O:
In programmed I/O, the CPU executes instructions to transfer data between the I/O device and memory. The CPU continuously polls the I/O device to check if it is ready to send or receive data. This method is simple and easy to implement, but it is also inefficient since the CPU has to wait for the I/O device to be ready before it can perform any other task.
Interrupt Driven I/O:
In interrupt-driven I/O, the CPU sends a command to the I/O device to start the data transfer, and then continues to perform other tasks. When the I/O device has completed the data transfer, it interrupts the CPU to signal that the data is ready. The CPU then stops its current task and processes the interrupt by executing an interrupt service routine (ISR) to transfer the data between the I/O device and memory. This method is more efficient than programmed I/O since the CPU can perform other tasks while waiting for the I/O device to complete the data transfer.
Direct Memory Access (DMA):
In Direct Memory Access (DMA), the I/O device can access the system memory directly without the intervention of the CPU. The I/O device sends a request to the DMA controller to initiate the data transfer, and the DMA controller transfers the data between the I/O device and memory without any involvement of the CPU. The CPU can continue to perform other tasks while the DMA controller performs the data transfer. This method is the most efficient of the three since it frees up the CPU to perform other tasks while the data transfer is being performed.
In summary, the main differences among programmed I/O, interrupt-driven I/O, and DMA are:
Programmed I/O is the simplest method of data transfer, but it is also the least efficient since the CPU has to continuously poll the I/O device to transfer data.
Interrupt-driven I/O is more efficient than programmed I/O since the CPU can perform other tasks while waiting for the I/O device to complete the data transfer.
DMA is the most efficient method of data transfer since it frees up the CPU to perform other tasks while the DMA controller performs the data transfer directly between the I/O device and memory.