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Chapter 12 : Configuring TCP/IP > Subnetting a Network - Pg. 502

502 Chapter 12 Configuring TCP/IP In a Class C network, the fi rst three bit positions are always binary 110. Three bytes, or 24 bits, minus 3 reserved positions leaves 21 positions. There are therefore 2 21 , or 2,097,152, possible Class C networks. The lead bit pattern of 110 equates to decimal 192 and runs through 223. Remembering our handy easy-recognition method, this means you can always spot a Class C address if the fi rst byte is in the range 192 ­223, regardless of the values of the second and third bytes of the IP address. Each unique Class C network has 1 byte to use for node addresses. This leads to 2 8 , or 256, minus the two special patterns of all 0s and all 1s, for a total of 254 node addresses for each Class C network. Class D networks, used for multicasting only, use the address range 224.0.0.0 to 239.255.255.255 and are used, as in broadcasting, as destination addresses only. Class E networks (reserved for future use at this point) cover 240.0.0.0 to 255.255.255.255 . Addresses in the Class E range are considered within the experimental range. Subnetting a Network