I am currently looking at some options to interface a fingerprint access system to my network. The device has an Ethernet port but I don’t want to run a cable from this to the router so I was thinking I could make a bridge device with a Cobra 3 and add WiFi and Ethernet to this.
The Ethernet port would be fixed IP and use a cross over cable. WiFi would be DHCP.
I want to capture the packets over the Ethernet port. The fingeprint device sends out UDP messages each time someone uses it. I will decode these and resend MQTT packets to the WiFi network for Node-red to handle the status of each user.
Should I use a different IP range for the Ethernet? eg, my main network is on 192.1678.1.x and I would put the Ethernet on 192.168.2.x or should I keep them the same and simply used a fixed IP for the fingerprint device and the Cobra 3 Ethernet that is outside the DHCP range setup on the router?
Has anyone done something like this and can confirm that this idea would work?