Technical note on subnet masking – Netopia R5300 User Manual
Page 244
B-6 User’s Reference Guide
There are two schemes for distributing the remaining IP addresses:
■
Manually give each computer an address
■
Let the Netopia R5000 Series 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 R5000 Series Router. Using the router in this way allows it to function as an
address ser ver.
One reason to use the Netopia R5000 Series 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 need
only enter information once, rather than having to enter it on each host separately. This also reduces the
potential for misconfiguring hosts.
Another reason to use the Netopia R5000 Series Router as an address ser ver is that it will distribute
addresses only to hosts that need to use them.
All Netopia R5000 Series Routers come with an integrated Dynamic Host Control Protocol (DHCP) ser ver. Some
routers also come with a Macintosh Internet Protocol (MacIP) ser ver. These ser vers provide a means of
distributing IP addresses to either a Mac or PC workstation as needed.
When setting up the DHCP or MacIP ser vers in the Netopia R5000 Series Router, it is necessar y to understand
how workstations lease, renew, and release their IP addresses. This information is helpful in determining
dynamic address allocation for a network.
The term “lease” describes the action of a workstation requesting and using an IP address. The address is
dynamic and can be returned to the address pool at a later time.
The term “renew” refers to what the workstations do to keep their leased IP address. At cer tain inter vals, the
workstation talks to the DHCP or MacIP ser ver and renews the lease on that IP address. This renewal allows
the workstation to keep and use the assigned IP address until the next renewal period.
The term “release” refers to a situation where the workstation is no longer using its assigned IP address or has
been shut down. IP addresses can be manually released as well. The IP address goes back into the DHCP or
MacIP address pool to be reassigned to another workstation as needed.
T
T
T
Tee
e
ecccch
h
h
hn
n
n
niiiiccccaa
a
allll n
n
n
no
o
o
ottttee
e
e o
o
o
on
n
n
n ssssu
u
u
ub
b
b
bn
n
n
nee
e
etttt m
m
m
maa
a
asssskk
k
kiiiin
n
n
ng
g
g
g
Note: The IP address supplied by the Netopia R5000 Series Router will be a unique number. You may want to
replace this number with a number that your ISP supplies if you are configuring the router for a static IP
address. The automatic IP mask supplied by Smar tStar t is a Class C address. However, the Netopia R5000
Series Router and all devices on the same local network must have the same subnet mask. If you require a
different class address, you can edit the IP Mask field to enter the correct address. Refer to the table below.
Number of Devices (other than
Netopia R5000 Series Router) on
Local Network
Largest Possible Ethernet Subnet
Mask
1
255.255.255.252
2-5
255.255.255.248
6-13
255.255.255.240