AP CSP: The Internet
What information is contained in a packet?
A small part of a digital message, and metadata about the message, including where it came from and where it is going
What happens when a new device is connected to the Internet?
An Internet Protocol (IP) address is assigned to the device.
True or False: Routing on the Internet is fault tolerant and redundant
True
True or False: When two computers are using the Transmission Control Protocol (TCP), the packets that they send to each other can be lost along the way, but they can be recovered via retransmission.
True, TCP is a data transport protocol that works on top of IP and includes mechanisms to improve the reliability, such as retransmission of lost packets.
What does URL stand for?
Uniform Resource Locator
Why do we need the Domain Name System (DNS)?
We need the domain name system because it would be too difficult to memorize the IP addresses of each website we wanted to visit. The DNS basically serves as an address book and translates each domain name to its IP address.
Given the domain name www.flamingflamingos.eu, what is the top level domain in this name?
The top level domain in this name is .eu.
What is the purpose of the Digital Millennium Copyright Act?
To criminalize the act of circumventing, or getting around, access controls that block access to copyrighted works.
What is the function of the Domain Name System (DNS)?
To translate domain names into IP addresses
What is the Internet Protocol (IP)?
A protocol that defines the structure of an Internet address and assigns a unique address to every device on the Internet
What is a DNS spoofing attack?
A hacker overwrites the data for a given domain name in a DNS server, causing the IP for that domain to point to the hacker's website rather than the intended website.
www.example.com/homepage.html 1. What is the domain in this URL? 2. What is the path in this URL? When this URL is typed into your browser, your browser generates a request based on the URL. 3. Where does this request get sent? What kind of machine is listening for this request? 4. What exactly is the request asking for? What does your browser expect to receive as a response?
1. The domain in this URl is www.example.com, and it tells the computer where to access the information. 2. The path in this URL is homepage.html and it tells the computer what you want to access. 3. The request gets sent from the computer to a server, which is waiting and listening for these requests. 4. The requests asks to access a certain resource based on the URL and you expect the server to send back a response so you can render the web page
Suppose we used an Internet Addressing protocol that used 4 bits to encode a single address. How many devices would be supported on the Internet? How many unique addresses would there be?
16
How many different nameservers need to be visited in order to find the location of www.flamingflamingos.eu, including the ROOT server?
3 different name servers: the root server, TLD server, and the hosting server
Which is the order of types of copyright license from most restrictive to least restrictive?
All Rights Reserved, Some Rights Reserved, Public Domain
How is the bandwidth of a network measured?
Bitrate. Higher bitrate means higher bandwidth.
What is the different between TCP and UDP protocols?
TCP included error checking mechanisms which can handle when packets are lost, out of order, or corrupted. UDP is a lightweight data transport protocol that
How do the TCP/IP protocols send data around the internet?
Computers split messages into packets and send them through routers to their final destination. The destination computer acknowledges the receipt of each packet, so that the sending computer can ensure every packet is delivered.
Once the location is acquired (IP address 88.151.243.8) what does your computer do with that information?
Store it in the cache so you have access to it next time
What is distributed computing?
Distrubuted computing sends tasks to different computers. While distributed computing is fault tolerant, scalable, and reliant, it can be complex and expensive to maintain.
True or False: For any two points on the Internet, there exists only one path between the two points
False
True or False: When two computers are using the Internet Protocol (IP), the packets that they send to each other can be lost along the way, but they can be recovered via retransmission.
False, when using IP, packets can be lost along the way. However, IP does not include mechanisms for recovering lost packets. TCP does, however.
In what situations does a computer use multiple Internet protocols to send a message? I. When it sends an encrypted message II. When it wants an acknowledgement that the destination computer received the message III. When it is loading webpage data
I, II, and III
Explain the difference between IPv4 and IPv6. Why are we currently undergoing a switch from IPv4 to IPv6?
IPv4 addresses can be represented in 32 bits, which means that there are over 4 billion possible IP addresses. IPv6 is represented with 128 bits and can has many more than 4 billion possibilities. We are currently undergoing a switch because as more and more people connect to the internet, we need to make sure there are enough possible IP addresses for all users.
How often is the Internet Protocol (IP) used in Internet communications?
It is used whenever two computing devices communicate with each other over the Internet.
What is parallel computing?
Parallel computing is faster becuase it can complete tasks simultaneously, but it is difficult to find bugs and use or set up correctly.
What is sequential computing?
Sequential computing completes one task at a time in order, and although it is easier to find bugs and no set up is needed, it can be slower.
Why do we need IP Addresses in order for the Internet to function properly?
Similar to how a mailing address is necessary to send information to a certain person or location, an IP address is necessary for people to communicate becuase the computers need to know where to send a certain message or information to. It is important to follow the standard protocol so each computer can understand how to read an IP address, and the information is presented to make the process as efficient as possible due to its hierarchical nature.
How does TCP can reassemble out-of-order packets?
The TCP metadata includes fields that describe where the packet belongs in the sequence.
What are the 4 steps of viewing a web page?
The URL: You type the URL for the web page into your browser The Request: The browser sends a message to a server requesting a resource The Response: The server sends a response to the browser with the resource attached Rendering the Page: Your browser takes the resource and renders it in the browser window
What is the relationship between the Internet and the World Wide Web?
The World Wide Web is built on top of the Internet; The World Wide Web is a system of linked pages, programs, and files that is accessed via a network called the Internet.
How is fault tolerance in a network achieved?
The ability to provide data transmission even when some connections between routers have failed
What is the bitrate of a system?
The amount of data (in bits) that can be sent in a fixed amount of time
What is bandwidth?
The maximum bit rate of a system
Tell the story of downloading an image from a website on the internet.
The story starts when you visit the URL, which is part of the World Wide Web, and your computer creates a HTTP request to access the site. Using the DNS, your computer is able to find the IP address and store it in the cache. It then uses TCP and IP protocols to break the request into packets. Packets are routed to the proper IP addresses and the original request is back together. The server uses this to create an HTTP response, and then uses TCP protocols to break the response into packets. The response packets are routed back to the computer and the original response is pieced together through the packets.
What is the latency of a system?
The time it takes for a bit to travel from sender to receiver
What does it mean for the routing system to be "redundant"? Is redundancy a good or bad thing?
When a routing system is "redundant" it means that multiple paths exist between the two same points. This is a good thing becuase it improves reliability (fault tolerant, when one path breaks there is another one to take) and makes the routing system scalable (added routers = better performance).
According to the Domain Name System (DNS), what is an example of a subdomain of the domain example.com?
about.example.com