JMU
The Internet Protocol (IP)
An Introduction


Prof. David Bernstein
James Madison University

Computer Science Department
bernstdh@jmu.edu


Overview
Frame Format
Moving through the Stack/Layers
IP Addresses
"Classfull Addressing"
images/ip-addresses.gif
IP Addresses (cont.)

A Class C (110...) Example

images/ip-addresses_example.gif
Assigning/Obtaining an IP Address
Sending from Source to Destination

From A to B (Within a Network)

images/ip-routing.gif
  1. Look up the address of B
  2. Find B is on the same network as A
  3. Link layer sends directly to B
Sending from Source to Destination (cont.)

From A to E (Between Networks)

images/ip-routing.gif
  1. Look up the address of E
  2. Find E is on a different network from A
  3. Learn that the appropriate router is 223.1.1.4
  4. Link layer sends packet to 223.1.1.4
  5. Packet arrives at 223.1.1.4 (destined for E)
  6. Look up the address of E
  7. Find E is on the same network as the router
  8. Router sends to E
Subnetting and Netmasks
Supernetting
IP Fragmentation and Reassembly
IP Fragmentation and Reassembly (cont.)
images/ip-fragmentation.gif
What's Different About IPv6?