150-357-200-02, Issue 2
Appendix B - Network Addresses
HXU-357 List 1
February 9, 1999
57
The IP address consists of two parts: the network ID (netid) and the host ID
(hostid). The subnet mask determines which bits form the netid and hostid
addresses. (See
Subnet Mask
A subnet is a physically separate part of a network, usually representative of
all the devices at one geographic location or on the same LAN. The subnet
mask is a quantity which is logically ANDed with an IP address to enable a
device to determine which IP addresses are located on the local network and
which addresses must go to the gateway for forwarding. An IP address of
200.200.200.1 and a subnet mask of 255.255.255.0, for example, indicates
that only IP addresses which start with 200.200.200 can be found on the local
physical network, and that all other addresses must go through the gateway.
(255 is the decimal representation of 8 bits of all ones.)
The subnet mask is also a 32-bit word, but it is generally a string of ones
followed by a string of zeroes. Each subnet bit that has a one value identifies
a corresponding bit of the IP address that is part of the netid. The zero bits
identify the hostid. The netid is further divided into five classes from A to E.
shows a Class C network address. Class C is recommended for most
Product Name applications. All Class C addresses are identified by the first
three bits (110). The hostid should not be assigned all ones or all zeroes.
Using the foregoing restrictions and conventions, a Product Name can be
assigned any IP address that meets your needs, provided that it is on its own
LAN and separated from any external network by a router. If this is not the
case, then consult your system administrator.
provides some
suggestions for addressing your system if it is on its own LAN. It shows a
logical relationship between the HMU and HXU units within each chassis.
Table 13.
Network Addressing
Subnet Mask
11111111 11111111 11111111 00000000
255.255.255.0
Class C
IP Address
110nnnnn nnnnnnnn nnnnnnnn hhhhhhhh
200.200.200.1
Class C
netid
hostid
