Asus RT-AC68R - Manual (Page 74)

Enable wildcard: Enable wildcard if your DDNS service
requires one.
NOTES:
DDNS service will not work under these conditions:
• When the wireless router is using a private WAN IP address (192.168.
x.x, 10.x.x.x, or 172.16.x.x), as indicated by a yellow text.
• The router may be on a network that uses multiple NAT tables.
4.3.6 NAT Passthrough
NAT Passthrough allows a Virtual Private Network (VPN)
connection to pass through the router to the network clients.
PPTP Passthrough, L2TP Passthrough, IPsec Passthrough and RTSP
Passthrough are enabled by default.
To enable / disable the NAT Passthrough settings, go to the
Advanced Settings > WAN > NAT Passthrough tab. When done,
click Apply.
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