Please people, what command prompt i ca use to now all IP addresses(all devices and COMPUTERS) on my network(LAN)
 Not sure what you need.
Start with ipconfig
Code: [Select]Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.
C:\Documents and Settings\Kohn>ipconfig
Windows IP Configuration
Ethernet adapter Local Area Connection 2:
        Connection-specific DNS Suffix  . : gateway.2wire.net
        IP Address. . . . . . . . . . . . : 192.168.1.71
        Subnet Mask . . . . . . . . . . . : 255.255.255.0
        Default Gateway . . . . . . . . . : 192.168.1.254
C:\Documents and Settings\Kohn>
You can use ipconfig /? to see options.
Does that help any?
Here is a list of references to ARCHIVE articles:
trace LAN IPs]
Yoy may have to look at the first twenty references to see if that relates to your request. Please come back and re state  your question.
I once used a batch program that tested for 1 to 255 for a defined address range.

similar to this:

Code: [Select]echo. Running Network IP Address Node Scan
echo. Please wait for the completed message in about 255 SECONDS
ping 192.168.1.1 -n 1 >>whatslive.log
ping 192.168.1.2 -n 1 >>whatslive.log
ping 192.168.1.3 -n 1 >>whatslive.log
ping 192.168.1.4 -n 1 >>whatslive.log
ping 192.168.1.5 -n 1 >>whatslive.log
....
....
....
ping 192.168.1.255 -n 1 >>whatslive.log
echo. Scan Completed
pause
with the .... portion covering the range of 192.168.1.6 thru 192.168.1.254 which I wasnt going to type that all out, but you get the point if you want to run with it placing it into a batch file. This could be seriously coded way better and a true false can be added to write to log file if the IP responds as successful or unsuccessful.

And then after 255 seconds its done scroll through the log file that is created and I know what IP's are in use.

As far as "Trace" if thats what you want to do, its a Traceroute from each system, but if you want to see all traffic I would suggest using a tool like wireshark in which you can CAPTURE all network traffic and see what systems were communicating in and outbound and you can save the capture file and dig deeper into it if needed. There is no command prompt utility I know of that works as WELL as wireshark and wireshark is a GUI application.