Thread: How to Detect the Computers on LAN

Hi People

I am working on a Messenger prepared in JAVA (Backend). I need something, some code that would help in finding the IP Address of the active computers on LAN.

Thanz
Arvind

If you ping the multicast address of the local LAN (which has the last client ID) every client will respond:

Example:
My IP address is 10.250.2.237 with 255.255.0.0 as netmask.
Thus, the multicast address for this network is 10.250.255.255

When I ping the multicast address, every client switched on will answer (although Windows' ping program will only show the first).

If you use a packet sniffer you will see every client that responds to the echo request.