3Com SuperStack 4 Configuration Manual page 72

84 C 5: N
HAPTER ETWORK
P O
ROTOCOL PERATION
The IP address is in dotted decimal format. Each IP address contains 4 integers in
dotted decimal notation. Each integer corresponds to one byte, for example,
10.110.50.101.
When using IP addresses, note that some of them are reserved for special uses,
and are seldom used. The IP addresses you can use are listed in
Table 76 IP Address Classes and Ranges
Network
class Address range
A 0.0.0.0 to
127.255.255.255
B 128.0.0.0 to
191.255.255.255
C 192.0.0.0 to
223.255.255.255
D 224.0.0.0 to
239.255.255.255
E 240.0.0.0 to
255.255.255.254
Other 255.255.255.255
addresses
Subnet and Mask
With the rapid development of the Internet, available IP addresses are depleting
very fast. The traditional IP address allocation method wastes IP addresses. In
order to make full use of the available IP addresses, the mask and subnet are used.
IP network range Note
1.0.0.0 to 126.0.0.0 Host ID with all the digits being 0
indicates that the IP address is the
network address, and is used for
network routing.
Host ID with all the digits being 1
indicates the broadcast address, that is,
broadcast to all hosts on the network.
IP address 0.0.0.0 is used for the host
that is not put into use after starting
up.
The IP address with network number as
0 indicates the current network and its
network can be cited by the router
without knowing its network number.
Network ID with the format of
127.X.Y.Z is reserved for self-loop test
and the packets sent to this address
will not be output to the line. The
packets are processed internally and
regarded as input packets.
128.0.0.0 to Host ID with all the digits being 0
191.254.0.0 indicates that the IP address is the
network address, and is used for
network routing.
Host ID with all the digits being 1
indicates the broadcast address, that is,
broadcast to all hosts on the network.
192.0.0.0 to Host ID with all the digits being 0
223.255.254.0 indicates that the IP address is the
network address, and is used for
network routing.
Host ID with all the digits being 1
indicates the broadcast address, that is,
broadcast to all hosts on the network.
None Addresses of class D are multicast
addresses.
None The addresses are reserved for future
use.
255.255.255.255 255.255.255.255 is used as LAN
broadcast address.
Table 76.