Comtrend Corporation NexusLink 3240u User Manual page 103

If the onboard DHCP server is running on "Default" and the remote DHCP server is
running on PVC 0/36 (i.e. for set-top box use only). LAN side clients can get IP
addresses from the CPE's DHCP server and access the Internet via PPPoE (0/33).
If a set-top box is connected to ETH1 and sends a DHCP request with vendor ID
"Video", the local DHCP server will forward this request to the remote DHCP server.
The Interface Grouping configuration will automatically change to the following:
1. Default: ETH2, ETH3, and ETH4
2. Video: nas_0_36, nas_0_37, nas_0_38, and ETH1.
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