Configuring Ip Addresses - H3C S5500-SI Series Operation Manual

Operation Manual – IP Address and Performance
H3C S5500-SI Series Ethernet Switches
Figure 1-2 Subnetting a Class B address
Note that subnetting is somewhat a tradeoff between subnets and accommodated
hosts. For example, a Class B network can accommodate 65,534 hosts before being
subnetted. After you break it down into 64 subnets by using the first 6 bits of the host-id
for the subnet, you have only 10 bits for the host-id and thus have only 1,022 (2
(excluding all-one broadcast addresses and all-zero network segment addresses)
hosts in each subnet. The maximum number of hosts is thus 64 × 1,022 = 65,408,
which is126 less than that before the network is subnetted.
Class A, B, and C networks, before being subnetted, use these default masks (also
called natural masks): 255.0.0.0, 255.255.0.0, and 255.255.255.0 respectively.

1.2 Configuring IP Addresses

An interface can obtain an IP address using the following methods:
Through manual IP address assignment
Through BOOTP
Through DHCP
These methods are mutually exclusive. An IP address obtained using a new method
overwrites that obtained using an old method. For example, if you manually assign an
IP address and then obtain another IP address through BOOTP, the IP address
obtained from BOOTP will overwrite the old one manually assigned. In this case, the
interface is assigned the IP address through BOOTP.
Note:
This chapter only covers how to assign an IP address manually. For how to obtain an IP
address using the other two methods, see the related sections in DHCP part of this
manual.
Chapter 1 IP Address Configuration
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