Finding unauthorized devices on my network

[TropicalBound]

Hi,

I am looking for a way to find unauthorized devices on my network. Let's say an employee brings in their personal laptop and connects to my network via CAT5, and they use a static IP Address, and have their Windows firewall turned on.

With a static IP, this laptop will not show up in DHCP
With the firewall turned on, this laptop will not return a ping

This is my dilemma. How can I know if someone is doing this?

Thoughts?

Thanks,

TB

[jdc2000]

You could try a free IP scanner program.

http://sourceforge.net/projects/ipscan/

http://www.advanced-ip-scanner.com/

[ecross]

With Windows Firewall enabled you need to allow ping (ICMP echo requests) through your firewall.

[TropicalBound]

Right. This is where my problem lies. If an unauthorized machine is on my network, and they have their firewall turned on, I won't have any idea their connected. This doesn't sit well with me.

[Train]

Got a router?

Mine has a way to list all ubits that access it.

[TropicalBound]

Unfortunately, my routers are managed by my data provider.

[SpywareDr]

You could try a free IP scanner program.

http://www.advanced-ip-scanner.com/

[TropicalBound]

SpywareDr, will the IP scanner work if the unauthorized device has a firewall enabled?

[SpywareDr]

Yes, the IP and MAC address. It's also real easy to try ... doesn't even have to be installed.

[Train]

Nice find Doc! Thank you!!

[SpywareDr]

You're welcome Train, but, (don't you hate that ), it was actually jdc2000 who mentioned it first up above.

[Train]

DUH, guilty of not paying strick attention again.

[TropicalBound]

Thank you gentlemen (whoever wants to take credit)!!! I scanned the network and found my 'test' PC. Then I enabled the firewall. The ping I had going timed out, but the IP Scanner still found it. Beautiful!!!

Thanks again!!

TB

[SpywareDr]

Excellent! And you're welcome.