Netopia 430 S/T, Справочное руководство

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Understanding IP Addressing C-9
must use the mask issued by the ISP). This, however, is not a
problematic limitation for your small network.
The advantages to this situation is the greater ease and lower cost
of obtaining a subnet from an ISP rather than a full Class C address.
Distributing IP addresses
To set up a connection to the Internet, you may have obtained a
block of IP host addresses from an Internet ser vice provider. When
configuring the Netopia ISDN Router, you gave one of those
addresses to its Ethernet por t, leaving a number of addresses to
distribute to computers on your network.
There are two schemes for distributing the remaining IP addresses:
■
Manually give each computer an address
■
Let the Netopia ISDN Router automatically distribute the
addresses
These two methods are not mutually exclusive; you can manually
issue some of the addresses while the rest are distributed by the
Netopia ISDN Router. Using the Router in this way allows it to
function as an address ser ver.
One reason to use the Netopia ISDN Router as an address ser ver is
that it takes less time than manually distributing the addresses.
This is par ticularly true if you have many addresses to distribute.
You only need to enter information once, rather than having to
repeatedly enter it on each host separately. This also reduces the
potential for misconfiguring hosts.
Another reason to use the Netopia ISDN Router as an address
ser ver is that it will only distribute addresses to hosts that need to
use them. If there is a shor tage of addresses, the address ser ver
will automatically take an address away from a host that has
stopped using it and give it to a host that is requesting one. If you
do not possess enough addresses for ever y host on your network to
have one at all times, using address ser ving to distribute them is
one solution. However, this is not an efficient solution because a