INNACOMM W3100V, Руководство пользователя

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If Enable NAT is disabled during the configuration, you must configure the route on
the BRAS. Otherwise, you cannot access your ISP. In actual application, Enable
NAT must be selected.
4.4 IP over ATM (IPoA) + NAT Mode
IP o ve r AT M
PC (s )
B R A S
ST M -1
D S L A M
A D S L
ISP
H u b
19 2.16 8 .1 .2
19 2.16 8 .1 .3
1 92 .1 68 .1 .1 20 .1 .1.2
2 0.1 .1.1
Description
In this example, the modem is connected to the DSLAM through PVC 8/35 and the
access mode is the IPOA+NAT. The downlink interface of BRAS is encapsulated in
1483R, the IP address is 20.1.1.1 , the IP address of the uplink interface is
10.61.92.157 , and the WAN IP address of the modem is assigned as 20.1.1.2 . The
PC attached to the modem is assigned with a private IP address (within the same
segment as the management IP address 192.168.1.1 ) . The NAT functions of the
modem is enabled, and the private address of the PC is translated into the public
address 20.1.* (2~254) dynamically assigned by BRAS for accessing ISP.
The IP address of the PC can be fixed (as in this example) or assigned through
DHCP Server of the modem. If it is assigned by DHCP server, the DHCP functions
of the modem must be enabled. The IP address of the DHCP address pool is
192.168.1 .* (2~254). The functions are enabled by default and at the same time
the PC is configured to obtain IP and DNS addresses dynamically.