Identify the current IP address of an adapter with known MAC address.
Computers connect to networks by using network adapters. Each network adapter has a Medium Access Control (MAC) address hardwired in its hardware. MAC addresses are unique world-wide, so a MAC address can be seen as a unique ID for a network adapter. At the Internet Protocol (IP) level, each computer connected to a network has an IP address. You can use Nmap, a security scanner application, to find out the current IP address of the computer whose MAC address you know.
Instructions
1. Log in to one of the computers on the Local Area Network (LAN) where the MAC address is.
2. Find out the network's mask and a sample IP address. The way of performing this step is operating-system dependent. For example, on Linux, type the command:
ifconfig
Press "Enter." The network mask is listed immediately after "Mask:," while the IP address is listed immediately after "inet addr:."
3. Convert the mask to binary, one number at a time. For example, if the mask from Step 2 is "255.255.240.0," its binary representation is "11111111.11111111.11110000.00000000"
4. Count the ones in the binary mask. For example, there are 20 ones in "11111111.11111111.11110000.00000000."
5. Probe all IP addresses allowed in the LAN by invoking Nmap as follows:
nmap -sP 192.168.132.2/2
Replace "192.168.132.2" by the IP address from Step 2. Replace "20" by the number of ones from Step 4. Press "Enter."
6. Find the MAC address you are searching. Once you find it, look a few lines up in the output until you find the legend "Host appears to be up." The IP-ADDRESS listed in that line of the output is the IP address you seek.
Tags: from Step, 11110000 00000000, 11111111 11110000, 11111111 11110000 00000000, 11111111 11111111