What is the gateway's DHCP Client-ID provided to a DHCP server during configuration procedure?

What is the gateway's DHCP Client-ID provided to a DHCP server during configuration procedure?

The gateway will provide its 12 digits long LAN MAC ID as DHCP Client-ID.

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  Does a gateway provide DHCP server based IP address assignment?
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  What is the gateway's DHCP Client-ID provided to a DHCP server during configuration procedure?
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  Which TCP/UDP ports are the gateways listening to by default?
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  If a gateway has a LAN port #2, what is its IP address?
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  Does a gateway provide non IP address based access using a hostname?