HP-UX LAN Administrator's Guide (Feburary 2007)

DRAFT COPY Network Addressing
Subnet Addresses
Chapter 7 105
Subnet Addresses
Subnetting is an optional addressing scheme that allows you to partition the host address
portion of an internet address into discrete subnetworks. This allows you to have multiple
physical networks without requiring you to obtain multiple network addresses. The physical
networks are connected via gateways.
For example, if you have a large installation with many interconnected nodes, you could run
into hardware configuration restrictions or performance degradation if you tried to place all
nodes on the same physical network. With subnetting you can install several smaller physical
networks but have them all share the same network address. When messages with subnet
addresses are routed across the network, the internet address is ANDed with the subnet
mask to determine the subnetwork address. (0 values in the subnet mask convert
corresponding bits in the IP address to 0.)