IPv4 and IPv6 Addressing

Question 1

The IP address of a device

Answer 1

• IP Address, e.g., 192.168.1.165
  
  • Every device needs a unique IP address

• Subnet mask, e.g., 255.255.255.0
• Used by the local workstation to determine what
subnet it’s on
• The subnet mask isn’t (usually) transmitted across
the network

• You’ll ask for the subnet mask all the time
  
  • What’s the subnet mask of this network?

Question 2

The secret behind the IP address

Answer 2

• The IP address isn’t really a single address.

• An IP address is a combination of a network ID and a
host ID
• The subnet mask determines what part of the IP
address is the network and which part is the host
• The subnet mask is just as important as your IP
address!

• The best way to see this work is in binary
  
  • This is the (very easy) math part

Question 3

IPv4 addresses - Internet Protocol version 4

Answer 3

• OSI Layer 3 address
• Since one byte is 8 bits, the maximum decimal value
for each byte is 255

Question 4

IPv6 addresses

Answer 4

• Internet Protocol v6 - 128-bit address
• 340,282,366,920,938,463,463,374,607,431,768,211,456
addresses (340 undecillion)

• 6.8 billion people could have 5,000,000,000,000,000,000,000,000,000 addresses each

Question 5

IPv6 address compression

Answer 5

• Your DNS will become very important!

• Groups of zeros can be abbreviated with a double
colon ::
• Only one of these abbreviations allowed per
address

• Leading zeros are optional