Seven Second Subnetting

 Seven Second Subnetting

  • Convert IP address and subnet mask to decimal
    • Use chart to convert between CIDR-block notation and decimal
    • Same chart also shows the number of devices per subnet
  • Determine network/subnet address
    • Second chart shows the starting subnet boundary 
  • Determine broadcast address
    • Chart below shows the ending subnet boundary 
  • Calculate first and last usable IP address
    • Add one from network address, subtract one from broadcast address

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