Day 7: Internet Protocols - Part 1

Learning Objectives

• CSN-1.E: For fault-tolerant systems like the Internet: a. Describe the benefits of fault tolerance. b. Explain how a given system is fault-tolerant. c. Identify vulnerabilities to failure in a system.

Essential Questions

• How does information travel across the Internet?
• What protocols enable reliable communication across diverse networks?
• How does packet switching work?

Materials Needed

• Presentation slides on Internet protocols
• Protocol simulation cards
• Packet assembly/disassembly worksheets
• Network protocol reference sheets
• Exit ticket templates

Vocabulary

• Protocol
• TCP/IP
• Packet switching
• IP (Internet Protocol)
• TCP (Transmission Control Protocol)
• UDP (User Datagram Protocol)
• Packet
• Header
• Payload
• Encapsulation

Procedure (50 minutes)

Opening (8 minutes)

1. Review and Connection (3 minutes)

   • Review Internet structure from previous lesson
   • Connect to today's focus on the protocols that enable Internet communication

2. Warm-up Activity (5 minutes)

   • Ask students: "If you and a friend speak different languages, how could you communicate?"
   • Discuss the need for shared rules and standards
   • Introduce the concept of protocols as agreed-upon rules for communication
   • Connect to the need for protocols in computer networks

Main Activities (32 minutes)

3. Lecture: TCP/IP and Packet Switching (12 minutes)

   • Define protocol as an agreed-upon set of rules that specify system behavior
   • Explain the TCP/IP protocol suite as the foundation of Internet communication
   • Discuss the layered approach of TCP/IP:
     • Application layer (HTTP, FTP, SMTP, etc.)
     • Transport layer (TCP, UDP)
     • Internet layer (IP)
     • Link layer (Ethernet, WiFi, etc.)
   • Explain packet switching:
     • Data divided into packets
     • Each packet contains header (metadata) and payload (data)
     • Packets can take different routes
     • Packets reassembled at destination
   • Discuss the benefits of packet switching:
     • Efficiency (shared network resources)
     • Resilience (multiple possible routes)
     • Scalability (works with any size network)
   • Explain IP addressing and routing basics

4. Demonstration: How Packets Are Routed (8 minutes)

   • Show how data is broken into packets
   • Demonstrate packet structure (headers and payload)
   • Illustrate how packets are routed through multiple networks
   • Show how packets might take different paths
   • Explain how packets are reassembled at the destination
   • Discuss what happens when packets are lost or corrupted
   • Show how TCP ensures reliable delivery

5. Activity: Modeling Packet Transmission and Reassembly (12 minutes)

   • Divide class into groups of 6-8 students
   • Assign roles: sender, receiver, routers, potential interference
   • Provide a message to be sent (e.g., a paragraph of text)
   • Sender divides message into "packets" (index cards with sequence numbers)
   • Routers pass packets along different paths
   • Interference occasionally blocks or delays packets
   • Receiver must reassemble the message in correct order
   • Discuss challenges encountered and how they were overcome
   • Relate activity to actual Internet protocols

Closing (10 minutes)

6. Discussion: Protocol Standardization (5 minutes)

   • Lead a discussion on why standardized protocols are important
   • Explain how protocols enable communication between different systems
   • Discuss the role of organizations like IETF in protocol development
   • Explain how the open nature of Internet protocols enables innovation
   • Address any misconceptions about Internet protocols

7. Exit Ticket: Protocol Stack Tracing (5 minutes)

   • Present students with a scenario (e.g., sending an email)
   • Students trace the path of data through the protocol stack
   • Students identify which protocols are involved at each layer
   • Students explain the role of each protocol
   • Collect responses before students leave

Assessment

• Formative: Participation in packet transmission activity
• Exit Ticket: Accuracy of protocol stack tracing

Differentiation

For Advanced Students

• Ask them to include more detailed protocol information in their tracing
• Have them explore protocol headers and specific fields
• Challenge them to explain how protocols handle specific error conditions

For Struggling Students

• Provide a simplified protocol stack diagram
• Focus on the most essential protocols
• Use more visual aids and concrete examples

Homework/Extension

• Research a specific Internet protocol and create a one-page summary
• Compare TCP and UDP protocols and their appropriate use cases
• Create a visual representation of the TCP/IP protocol stack

Teacher Notes

• Use analogies to help students understand protocols (e.g., postal system for addressing and delivery)
• Be prepared to address questions about specific protocols
• Make connections to students' everyday Internet experiences
• Consider using packet sniffing tools to show actual network traffic (with appropriate permissions)
• Emphasize that understanding protocols helps with network troubleshooting and security