Lantronix XPort - Manual (Page 64)

IP Addresses
Class Address Range Comments
223.255.254.254
D 224.0.0.0 to
239.255.255.254
Reserved for multicast groups
E 240.0.0.0 to
254.255.255.254
Reserved for experimental and future use
Consider the IP address 36.1.3.4. This address is a Class A address; therefore,
the network portion of the address is 36.0.0.0 and the host portion is 1.3.4.
Subnet Portion
The subnet portion of the IP address represents which sub-network the address
is from. Sub-networks are formed when an IP network is broken down into
smaller networks using a subnet mask.
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.
Host Portion
The host portion of the IP address is a unique number assigned to identify the
host.
Network Address
A host address with all host bits set to 0 addresses the network as a whole (as in
routing entries), for example, 192.168.0.0.
Broadcast Address
A host address with all host bits set to 1 is the broadcast address (for every
station), for example, 192.168.0.255.
You may not use a network or broadcast address 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 an IP address differently from 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 unit prompts for
the number of host bits to be entered and then calculates the netmask, which
displays in standard decimal-dot notation (for example, 255.255.255.0) after you
save the parameters.
Table 9-7. 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
9-2 XPort™ User Guide