Tasks

25.1 Networks and Internet Review - Worksheet Part 1

• While students have a basic understanding of the workings of the Internet, this serves as a review and uses videos that up the level of technical knowledge presented. 
• The worksheet is here
• The assignment is in two parts and contains links to the videos within but I recommend watching each video first and reiterating the concepts together, then assigning the worksheet.
  • See the doc in the Shared Resources Folder for the student worksheet
• Watch Video 1: Computer Networks: Crash Course Computer Science #28 [12:19]

• Related concepts including these AP CSP Essential Knowledge Statements:
  • A path between two computing devices on a computer network (a sender and a receiver) is a sequence of directly connected computing devices that begins at the sender and ends at the receiver.  
  • Paths are often measured in Hops
  • Routing is the process of finding a path from sender to receiver.
  • The bandwidth of a computer network is the maximum amount of data that can be sent in a fixed amount of time. 
  • Bandwidth is usually measured in bits per second. 
  • Information is passed through the Internet as a data stream. Data streams contain chunks of data, which are encapsulated in packets.
  • Packets contain a chunk of data and metadata used for routing the packet between the origin and the destination on the Internet, as well as for data reassembly.
  • Packets may arrive at the destination in order, out of order, or not at all.
  • IP, TCP, and UDP are common protocols used on the Internet.
  • The Internet has been engineered to be fault-tolerant, with abstractions for routing and transmitting data. 
  • Redundancy is the inclusion of extra components that can be used to mitigate failure of a system if other components fail.
  • One way to accomplish network redundancy is by having more than one path between any two connected devices.
  • If a particular device or connection on the Internet fails, subsequent data will be sent via a different route, if possible.
  • When a system can support failures and still continue to function, it is called fault-tolerant. This is important because elements of complex systems fail at unexpected times, often in groups, and fault tolerance allows users to continue to use the network.
  • Redundancy within a system often requires additional resources but can provide the benefit of fault tolerance.
  • The redundancy of routing options between two points increases the reliability of the Internet and helps it scale to more devices and more people.

25.2 How Networks and the Internet Work - Worksheet Part 1

• Have the students complete the first half of the worksheet based on video 1

25.3 In-School Field Trip - Map the Network

• Arrange to visit your school’s server room and/or get support from your school’s network administrator
• Trace the number of hops it takes to get from a student device out to the server (switches along the way)
• Discuss what additional hops it takes at the district level before reaching the school’s ISP and the Internet backbone
• Optional: have students create a visual demonstrating these hops

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Continue to Unit 2: Day 11 »