Detect MAC Addresses? - via browser, without a plugin

For validation purposes,开发者_高级运维 is there a way to detect a user's mac address as they're signing up on a webpage, for example? I'd prefer a LAMP approach, but also open to ASP.NET possibilities.

I guess you could by reading the ARP cache of the underlying OS, assuming that the client and server are on the same network.

However, using the MAC address for validation is under most circumstances a bad idea:

• The MAC address can be easily spoofed. Many network drivers allow you to set the address to whatever you want.

• The MAC address is link local. If there is at least one router between the server and the client, the server will see the closest routers MAC address.

Trying to detect mac-addresses is not a good idea.

But you can use a Java Applet to do so. The user will have to allow it to run though.

The Java Applets can be embedded in any webpage

Here is how you do it http://techdetails.agwego.com/2008/02/11/37