Lecture 7.pdf

The Network Layer

The Internet Protocol -IP

In the network layer the IP protocol is standing

• IPv4 addressing (32-bit addressing)
• moving a datagram from source to destination
• datagram format
• IP fragmentation
• ICMP: Internet Control Message Protocol
• DHCP: Dynamic Host Configuration Protocol
• NAT: Network Address Translation
• Routing

IP Addressing

• interface
  • connection between host/router and physical link
  • routers typically have multiple interfaces
  • host may have multiple interfaces
• IP address
  • 32-bits identifier for host, router interface (IPv4) ⇒ 2^32 IPs
  • 128-bits identifier for host, router interface (IPv6)
  • associated with each interface

    • network part (high order bits)

    • host part (low order bits)

      

What’s a network? (from IP address perspective)

• device interfaces with the same network part of IP addresses