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Ignitionnet · 22-04-2015, 14:52

Subnet and NAT are not needed. Your devices send to 192.168.100.1 via the modem as it's the default gateway. It knows the MAC address it needs to send to as it's in the same broadcast domain, no need for any IP routing and the traffic never leaves your home network.

It looks for traffic with a destination of that IP address and internally forwards it to its management interface, again no IP routing.

Simple as that.

EDIT: By the way cable modems are not pure modems, they are also bridges. They have full layer 3 (and actually some layer 4!) functionality and have an external-facing IP address whether or not in bridge mode. When in bridge mode they do just that, bridge, they don't just convert from RF to Ethernet like an unmanaged basic modem would.

22-04-2015, 14:52	#2
Ignitionnet Inactive Join Date: Jun 2008 Location: Leeds, West Yorkshire Age: 47 Posts: 13,995	Re: Bridge mode UI? Subnet and NAT are not needed. Your devices send to 192.168.100.1 via the modem as it's the default gateway. It knows the MAC address it needs to send to as it's in the same broadcast domain, no need for any IP routing and the traffic never leaves your home network. It looks for traffic with a destination of that IP address and internally forwards it to its management interface, again no IP routing. Simple as that. EDIT: By the way cable modems are not pure modems, they are also bridges. They have full layer 3 (and actually some layer 4!) functionality and have an external-facing IP address whether or not in bridge mode. When in bridge mode they do just that, bridge, they don't just convert from RF to Ethernet like an unmanaged basic modem would.