MAC address to IP Address

Hi Guys,

Do you have any idea on how to convert MAC address to IP address?

Any suggestions is highly appreciated. Thanks for your help.

Cheers!
Gagamboy

Heya gagamboy,

Just out of curiosity, why do you need to convert a MAC address to an IP address?

Found this comment when doing a Google search for, "converting MAC to IP"

You have to use arp. Remember that MAC addresses are used at layer 2 and IP is layer 3. You will only be able to see MAC addresses that are in the same broadcast domain (on your subnet). The easiest way is if you have a list of MAC addresses, then ping the broadcast address(x.x.x.255 for a class c) of your subnet. Then if you do an arp -a, you will get a list of all the ip's along with the MAC address for you subnet. Then you can do a 1 to 1 match with your 2 lists.
Source: www.experts-exchange.com/Networking/Misc/Q_20167638.html

I'm not sure if your looking for a program to do the conversion, or if running the arp command will suffice.

Hope that helps.


Cheers,

ZiPPy

I suppose that a possible reason might be when dealing with Multicast addresses though I realise that this is not common.

Thanks Zippy, I appreciate it.

I am using it to support our client, to be exact I want to verify the PC if it changed the IP add once I change its VLAN by looking its mac-address only.

arp -a is good solution for this, but is there any program that caters conversion of mac to ip? I am looking at the google but no luck.

Cheers!
Gagamboy

I'm not really sure of any programs to accomplish exactly what you need. I've used arp -a in the past to verify MAC addresses on the firewall. So, that really might be your best bet right now.

Unless somebody has an app that can do this for you, or maybe even somebody who could create a quick program. Are you looking for something that will consistently update itself of the changes?


ZiPPy

Your looking for a tool that can do some thing called Inverse ARP for Ethernet. Unfortunately, such a tool is very rare if it exists. Besides, Inverse ARP is usually only used in Frame Relay and ATM networks.

Another option is to use arping. mathieu.carbou.free.fr/wiki/index.php?ti..._arping_under_Cygwin
It has many features including pinging a PC by it's MAC address and it can be used to find out an IP address from a given MAC. However, I have to say that it's not very easy to use.

Probably the easiest way is what Zippy suggested. You could also use SoftPerfect Network Scanner:

www.softperfect.com/products/networkscanner/

It will discover all hosts on you network and give a whole lot of info about them including their MAC addresses.