How to find unused IP Address on a network?
currently I am using nmap wich scans the range of IPs that my DHCP server assigns to hosts. However this is a) slow and b) sometimes nmaps doesn't discover all hosts. Laptops that are connected wirelessly sometimes aren't counted.
I tried almost all possible nmap scan techniques like:
sP,sS, sT, sW, sM etc... they all miss out the laptops sometimes although I can ping them at any time.
I am looking for an efficient way to accomplish this without missing out some hosts. My Router is a Linksys WRT54GL and I am using the latest Tomato firmware.