Installing and Administering LAN/9000 Software

Chapter 6 141
Network Addressing
Subnet Addresses
Figure 6-5 Internet Address 192.6.12.33 ANDed with Subnet Mask
255.255.255.224
When the internet address is ANDed with the subnet mask, the zero
values in the host portion of the subnet mask will “overwrite” the
corresponding bits of the host portion of the internet address and the
resultant subnet address will be 192.6.12.32 as shown in Figure 6-5
above. Non-zero values in the subnet mask indicate that the
corresponding bits in the internet address do not change. The subnet
mask may be fixed-length or variable-length.
Selecting a Subnet Addressing Scheme
In addition to fixed-length subnet addressing, with the HP-UX 10.01
11 111 11 111 11 111 1 1111 110011111 000
11 000 00 011 00 000 1 1000 010000000 001
11 000 00 011 00 000 1 1000 010000000 000
255 . 255 . 255 . 224
Subnet
Mask
AND
0 values in mask (00000)
192 . 6 . 12 . 33
Internet
Address
Convert
to
Subnet
Address
overwrite value of 1 (00001)
in IP address
Bit values unchanged
Bit values
converted to
zero
resulting in new value
(00100000) in host address
(or 32 in dot notation)
192 . 6 . 12 . 32