Draytek Vigor2500V Manual page 112

Enable
: Tick this to enable this entry.
Phone Number
: The number you want to dial from your handset to call this contact.
This can be any number you choose, using digits 0-9 and*
SIP Address
: Enter the SIP address of your contact (e.g. 98141@draytel.org)
Loop Through: The Vigor2500V has a "Line" port on the rear panel for
connecting to a PSTN (regular analogue) line. The Loop Through option can
be used to set an alternate telephone number for your contact on the PSTN,
which the Vigor2500V will dial instead of the SIP account if you lose ADSL
access or power to the Vigor2500V. Hence, the PSTN line can act as a
lifeline (backup mechanism) for VoIP calls. The lifeline mechanism is activated
automatically but can also be manually configured.
Because there is ISDN interface on the Vigor2500Vi series, you can use the
ISDN line as phone line as well as Internet remote access/dial back-up for
ADSL. You will be able to still make ISDN phone calls if the router loses
power or the VoIP calls can not make as Internet access is broken. Hence,
the ISDN line can also be lifeline (backup mechanism) for VoIP calls.
VoIP
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