IP Classes
•Default Network
0.0.0.0
•Class A
first octet in 1-126. Alone forms net
first octet starts with 0
other 3 octets for host
half of total ips
•Loopback
127.0.0.1
•Class B
first octet in 128-191. Together
with second octet form net
1st octet starts with 10
quarter of total ips
•Class C
first octet in 192-223
1st octet starts with 110
2^21 Class C networks
each has 254 (2^8-2) hosts
1/8 total ips
•Class D
used for multicast
1st octet starts with 1110
1/16 total ips
•Class E
used for experiments
1st octet starts with 1111
1/16 total ips
•Broadcast
255.255.255.255
•Subnetting
Moving bits to the network portion of the IP address.
2^x – 2 = Number of addresses
x is number of bits in the address
256 – x = y limit x
x: new subnet mask