Software like: TNM, Nmap, NetCrunch Tools

Hello,

I’m looking for FREE application or software alternative to: TNM, Nmap, NetCrunch.

I’m searching software where i can: Ping, Scan lot of Private Subnets, view MACs, Reboot devices or Wake-On-Lan.

The important point for me is to scan unlimited devices.

Finlay, thanks & Best regards.