Learning the Packet Delivery Process

Learn the basics of the packet delivery process to understand how protocols and ports work together to deliver data to the proper destination.

Introduction

• Data packet delivery across local and remote networks
• What you should know

1. Understand Network Technologies

• Understand differences between domains and local networks
• Distinguish among nodes, switches, and routers
• Understand the purpose of DHCP
• Dissect the IP address: Network and host
• Understand the importance of the MAC address
• Understand the data packet and TTL
• Challenge: Locate and name all nodes on a locate network
• Solution: Locate and name all nodes on a locate network

2. Explore Network Models

• Explore the OSI model
• Explore the TCP/IP model
• Learn the purpose of the application layer
• Learn the purpose of the transport layer
• Learn the purpose of the network layer
• Learn the purpose of the network access layer
• Challenge: Compare mailing a letter to the TCP/IP model
• Solution: Compare mailing a letter to the TCP/IP model

3. Understand Network Ports and Protocols

• Learn port basics
• Explore ports 20, 21, 22, 23, 25, and 53, 80, 443
• Learn protocol basics
• Understand the three-way handshake
• Challenge: Show a port running, listening, and closed
• Solution: Show when a port is running, listening, and closed

4. Learn the Data Preparation Process

• Understand data encapsulation
• Understand the protocol data unit (PDU)
• Learn more about PDU headers
• Understand data de-encapsulation
• Challenge: Show TCP and UDP packets in a traffic analyzer
• Solution: Show TCP and UDP packets in a traffic analyzer

5. How Packet Delivery Works with Local Hosts

• Step 1: A workstation sends data (local)
• Step 2: The packet acquires delivery information (local)
• Step 3: ARP helps locate MAC addresses (local)
• Step 4: Network hardware reads, updates, and routes (local)
• Challenge: Test for and remediate packet loss
• Solution: Test for and remediate packet loss

6. How Packet Delivery Works with Remote Hosts

• Step 1: A workstation sends data (remote)
• Step 2: The packet acquires delivery information (remote)
• Step 3: ARP helps locate the MAC addresses (remote)
• Step 4: Network hardware reads, updates, and routes packets
• Challenge: Diagnose packet loss to a remote network
• Solution: Diagnose packet loss to a remote network

Conclusion

• Next steps with packet delivery