anthony morris

IP Address

  • Static or dynamic
    • Static IPs assigned by network administrators
    • Dynamic IPs assigned by DHCP server


  • 32 bits
  • Written as four decimal numbers called octets
    • Each octet can be any number from 0 to 255

Private IPs

  • A company can use private IPs on its private networks
  • IEEE recommends the following:
    • through
    • through
    • through


  • Dividing line between network and host portions is determined by numerical range IP address falls in
  • Class A, B, and C are available for use on the internet
    • Public IP addresses
  • Classes D and E are not available for general use:
    • Class D begins with octets 224-239 --> use for multicasting
    • Class E begins with octets 240-254 --> used for research
Class Network octets Approx. number of possible networks Approx. number of IP addresses in each network
A 1.x.y.z to 126.x.y.z 126 16 million
B 128.0.x.y to 191.255.x.y 16,000 65,000
C 192.0.0.x to 223.255.255.x 2 million 254

Reserved IPs

IP Address(es) Function Used to broadcast messages by TCP/IP background processes. Message is read by every node on the network. Unassigned through Uses for research or your own computer (loopback address) through Used to create APIPA address when a computer configured for DHCP first connects to the network and is unable to lease an IPv4 address from DHCP server.


  • 128 bits
  • Written as eight blocks of hexadecimal numbers

Computer Science Networking