OSI model

• Purpose of physical, data link, network, transport, presentation layers
• Which layers are used by IP

Data Link Layer

• Local Area Network (LAN)
• Ethernet - service guarantees

Network Layer

• Internet Protocol (IP)
• connectionless service
• IP principles: survivable, decentralized design, routing
• delivery guarantees

Transport Layer: TCP & UDP

• TCP
  • Connection-oriented service, full-duplex connections, reliable & in-order data delivery
• UDP
  • Connectionless service and UDP's delivery guarantees

Understand the concept of layering in network protocols

Clients and servers and services

Transport endpoints (ports) vs. network endpoints (addresses)

Data link addressing vs. network addressing: MAC address vs IP address

Protocol encapsulation concept

• Ethernet device driver: encapsulate IP within an ethernet packet
• IP: encapsulates UDP or TCP packets within an IP packet