I would like to make a presence detection application which would be able to detect when a known device connects to the local Wifi network. So basically I would know the MAC address of the device, but the IP is dynamically assigned so it can change.
I can only rely on the known MAC to determine if the device is here or not, how can I do that ?
I have thought about one possibility :
do a broadcast ping on my network (ping the 255 possibly IPs).
then do a arp request and look into the ARP table and try to find the known MAC
if I find it, the device is here and I can see the IP, if the MAC is not there then the device is not on the network
This could possibly work but it is not smart and requiers a permanent ping broadcast which can be slow in some cases according to my experiments. And it would not be energy efficient as well.
I am from Electrical Engineering and don't have a huge background into networks, so please pardon my maybe dumb question. Hope somebody will be wiling to help me :)