Getting the MAC address of the client in asp.net

I need some way of getting the clients MAC address in asp.net

The problem is that I can´t use sessions and I cant use cookies, but I need to store info about the client temporarily, my solution to this is to create a table in SQL for storing the client info...

However, I need a way to Identofy that client to the SQL table...

ok, so, I thought of the MAC adress...

Ive been useing the IP address, however, if someone is sitting on a corporate network, they can have the same externat IP so it does not work...

I need the MAC address or some other unique ID from the client witch does not change depending on witch page the user enters...

Is there a way of getting the MAC address (or other unique id) from the user in a simple and reliable way from the client in asp.net (VB)
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