Draytek Vigor3910 Series User Manual page 54

DNS Server IP Address
WAN Connection
Detection
MTU
44
Specify an IP address – Click this radio button to specify
some data if you want to use Static IP mode.

IP Address: Type the IP address.

Subnet Mask: Type the subnet mask.

Gateway IP Address: Type the gateway IP address.
WAN IP Alias - If you have multiple public IP addresses and
would like to utilize them on the WAN interface, please use
WAN IP Alias. You can set up to 32 public IP addresses other
than the current one you are using.
Type in the primary IP address for the router if you want to
use Static IP mode. If necessary, type in secondary IP address
for necessity in the future.
Such function allows you to verify whether network
connection is alive or not through ARP Detect or Ping Detect.
Mode – Choose ARP Detect, Ping Detect, Always On or Strict
ARP Detect for the system to execute for WAN detection. If
you choose Ping Detect as the detection mode, you have to
type required settings for the following items.

Primary/Secondary Ping IP – If you choose Ping Detect as
detection mode, you have to type Primary or Secondary IP
address in this field for pinging.

Ping Gateway IP – If you choose Ping Detect as detection
mode, you also can enable this setting to use current WAN
gateway IP address for pinging.
With the IP address(es) pinging, Vigor router can check if
the WAN connection is on or off.

TTL (Time to Live) – Set TTL value of PING operation.

Ping Interval – Type the interval for the system to
execute the PING operation.

Ping Retry – Type the number of times that the system is
allowed to execute the PING operation before WAN
disconnection is judged.
It means Max Transmit Unit for packet.
Path MTU Discovery – It is used to detect the maximum MTU
size of a packet not to be segmented in specific transmit
path.
Click Detect to open the following dialog.
 Path MTU to – Type the IP address as the specific
transmit path.
MTU size start from – Determine the starting point

value of the packet. Default setting is 1500.
 MTU reduce size by– It determines the decreasing size
of MTU value. For example, the number specified in
this field is "8". The maximum MTU size is "1500".
Vigor3910 Series User's Guide