Draytek Vigor2920n User Manual page 79

SIP URL
Dial Out Account
Loop through
Backup Phone Number
Enter your friend's SIP Address.
Choose one of the SIP accounts for this profile to dial out. It is
useful for both sides (caller and callee) that registered to
different SIP Registrar servers. If caller and callee do not use
the same SIP server, sometimes, the VoIP phone call
connection may not succeed. By using the specified dial out
account, the successful connection can be assured.
Choose PSTN to enable loop through function.
When the VoIP phone is obstructs or the Internet breaks down
for some reasons, the backup phone will be dialed out to replace
the VoIP phone number. At this time, the phone call will be
changed from VoIP phone into PSTN call according to the loop
through direction chosen. Note that, during the phone switch,
the blare of phone will appear for a short time. And when the
VoIP phone is switched into the PSTN phone, the telecom co.
might charge you for the connection fee. Please type in backup
phone number (PSTN number) for this VoIP phone setting.
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Vigor2920 Series User's Guide