IP Addresses

IP (Internet Protocol) addresses are assigned to each device connected to a network. A device or web page can be identified by its IP addresses, as all are unique - like a postal address. There are also private IP addresses, which can be used in an internal network but not on the Internet at large.

• Lecture

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  • Lecture Notes

• Short

  • IP

• Notes

  • IP Addresses

• Supplementary Resources

  • Khan Academy on IP Addresses and DNS

• Thought Questions

  • Can you think of potential problems if two devices were to have the same IP address on a network? (Hint: It would be very difficult to discern which device was performing which operations, such as with MAC spoofing.)
  • What do you think will happen when we run out of valid IP addresses? (Hint: A temporary solution has been created, but it’s not perfect.)
  • If currently connected to the Internet, what is your computer’s IP address? Will it always stay the same? If it changes, why might that be?