So Let's start with this diagram. (Note that none of equipment cannot be moved.)
I want to connect MT#1 which is in Room#1 to MT#2 (MT#1 is DHCP client here and MT#2 is DHCP server.)
Clearly I need to wire another CAT cable from Room#1 to Room#2. However, I want to ask that can I connect MT#1 to DSL modem (using red wire) instead of connecting MT#1 to MT#2?
I heard something about VLAN but I am not sure how this can help in this scenario.
I have 2 rooms. In Room#2, there is a MT router (MT#2), connected by a 10m CAT6 cable as PPPoE interface to DSL modem which is in bridge mode itself and located in Room#1.