IP scanners list

Hi everyone,
I have a question hoping one of you can help me since I’ve seen some great advices to some questions before.
I am using Free IP Scanner to scan my network, but I see some IP using lots of trafic in my network and the Free IP Scanner doesn’t show those Host Names or MAC Addresses only the IP that is in used.
I have a SonicWALL monitoring the network, thank you in advance.