UDP
UDS-10 User Guide
8-15
A router is required between all networks and all sub-networks. Generally, hosts can send
packets directly only to hosts on their own sub-network. All packets destined for other
subnets are sent to a router on the local network.
8.4.3 Host Portion
The host portion of the IP address is a unique number assigned to identify the host.
8.4.4 Network Address
A host address with all host bits set to 0 addresses the network as a whole (for example, in
routing entries).
192.168.0.0
8.4.5 Broadcast Address
A host address with all host bits set to 1 is the broadcast address, meaning for “for every
station.”
192.168.0.255
Network and broadcast addresses must not be used as a host address; for example,
192.168.0.0 identifies the entire network, and 192.168.0.255 identifies the broadcast address.
IP Subnet Mask
An IP subnet mask divides IP address differently than the standards defined by the classes A,
B, and C. An IP subnet mask defines the number of bits to be taken from the IP address as the
network or host sections. The Device Server prompts for the number of host bits to be entered
and then calculates the netmask, which is displayed in standard decimal-dot notation (for
example, 255.255.255.0) when saved parameters are displayed.
Table 33 - Standard IP Network Netmasks
Network Class Network Bits Host Bits Netmask
A 8
24
255.0.0.0
B 16
16
255.255.0.0
C 24
8
255.255.255.0
