The 2-Wire-LAN is a 2wire system of convertors for use in any type of building 

Long-range ethernet extension over a 2-wire pair

Full-duplex high-speed Ethernet data signal over two-wire cable

Automatic negotiation data throughput

High data rate - up to four IP Intercoms and Mega-pixel cameras

IEEE 802.3 af/at compliant PoE for IP Intercom and IP camera power supply

Plug & Play configuration, no IP address, no network setup needed

LED indicator for installation - Power, Link and Data traffic status

Using your standard two-wire cable, you can extend data signal 10/100 BaseT to a distance of a maximum of 300m.

Use legacy analog wires of your old intercom or CCTV to connect your IP camera, IP intercom, IP phone, and other IP devices.

Advantage of the 1:4 system: The 2-Wire-LAN master unit can support up to 4 slave units

Any 2-Wire-LAN unit can be master or slave, the units are the same

The selected master unit is powered via a 48VDC power supply adapter

Up to four PoE powered IP devices can be connected via slave units to one 2-Wire-LAN master unit

Check more details at https://www.2-wire-lan.com/