Arpscan

Arpscan is a utility that scans local network using ARP protocol and reports hosts alive. Program is designed for Linux.

arpscan [-saepwlV] [interface] [ip-range]
        -s  sort responses
        -a  do not list interface's own address
        -e  do not include info from /etc/ethers
        -p  print vendor names
        -w  slow operation
        -l  listen only (not promiscuous)
ip-range: ip ip/bits ip-ip