User's Manual

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ENABLE FULLCONE NAT
This option becomes available when NAT is enabled. Known as
one-to-one NAT, all requests from the same internal IP address
and port are mapped to the same external IP address and port. An
external host can send a packet to the internal host, by sending a
packet to the mapped external address.
DIAL ON DEMAND
The DSL-N12HP can be congured to disconnect if there is no
activity for a period of time by selecting the Dial on demand
checkbox. You must also enter an inactivity timeout period in the
range of 1 to 4320 minutes.
PPP IP EXTENSION
The PPP IP Extension is a special feature deployed by some service
providers. Unless your service provider specically requires this
setup, do not select it.
PPP IP Extension does the following:
• AllowsonlyonePContheLAN.
• DisablesNATandFirewall.
• ThedevicebecomesthedefaultgatewayandDNSserverto
the PC through DHCP using the LAN interface IP address.
• ThedeviceextendstheIPsubnetattheremoteservice
provider to the LAN PC. i.e. the PC becomes a host belonging
to the same IP subnet.
• ThedevicebridgestheIPpacketsbetweenWANandLAN
ports, unless the packet is addressed to the device’s LAN IP
address.
• ThepublicIPaddressassignedbytheremotesideusing
the PPP/IPCP protocol is actually not used on the WAN PPP
interface. Instead, it is forwarded to the PC LAN interface
through DHCP. Only one PC on the LAN can be connected to
the remote, since the DHCP server within the device has only
a single IP address to assign to a LAN device.