User's Manual

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CONFIGURE KEEP-ALIVE
Configures the interval and number of keep alive packets (PPP echo-request) sent
by the device for the PPP connection.
Interval (second): Time between sending out each PPP echo-request packet.
Number of retries: Number of retries before PPP connection is dropped.
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 VR-3071 can be configured 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.
ENABLE FIREWALL
If this checkbox  is selected, the Security submenu will be displayed on the
Advanced Setup menu after reboot. If firewall is not necessary, this checkbox 
should not be selected to free up system resources for better performance.
USE STATIC IPv4 ADDRESS
Unless your service provider specially requires it, do not select this checkbox . If
selected, enter the static IP address in the IP Address field. Also, don’t forget to
adjust the IP configuration to Static IP Mode as described in 3.2 IP Configuration.
USE STATIC IPv6 ADDRESS
Unless your service provider specially requires it, do not select this checkbox . If
selected, enter the static IP address in the IPv6 Address field.
Don’t forget to adjust the IP configuration to Static IP Mode as described in section
3.2 IP Configuration.
ENABLE IPv6 UNNUMBERED MODEL
The IP unnumbered configuration command allows you to enable IP processing on a
serial interface without assigning it an explicit IP address. The IP unnumbered
interface can "borrow" the IP address of another interface already configured on the
router, which conserves network and address space.
LAUNCH DHCP6C FOR ADDRESS ASSIGNMENT (IANA)
The Internet Assigned Numbers Authority (IANA) is a department of ICANN
responsible for coordinating some of the key elements that keep the Internet
running smoothly. Whilst the Internet is renowned for being a worldwide network
free from central coordination, there is a technical need for some key parts of the
Internet to be globally coordinated, and this coordination role is undertaken by
IANA.
Specifically, IANA allocates and maintains unique codes and numbering systems
that are used in the technical standards (“protocols”) that drive the Internet.
IANA’s various activities can be broadly grouped in to three categories:
• Domain Names
IANA manages the DNS Root, the .int and .arpa domains, and an IDN practices
resource.