Draytek Vigor2920 Series User Manual page 430

Port-based mode
Tag-based mode
To deploy a guest network, which serves your guests the internet accessibility, but the
traffics have to be isolated from your private network due to the security considerations,
it can be done by above settings. However, a switch support VLAN function is need if
VLAN Tag enabled.

Triple Play (Multi-WAN)
NAT mode with VLAN
Vigor2920 Series User's Guide
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