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Re: [LUG] MAC address on Android

 


On 13/01/14 17:55, Gordon Henderson wrote:
On Mon, 13 Jan 2014, George Parker wrote:

Thanks to you all but I think that Grant has the answer here. I am looking at my router client list and if I switch off the wi-fi on my phone, then back on again it reconnects with a different MAC.

What a strange phone.

The whole point of the MAC is that it never changes - it's unique for each device. It's not supposed to change. The manufacturer is supposed to assign a unique MAC for every device they make - and once upon a time I was the person responsible in a company making network devices to ensure that all our products did get a unique MAC...

I've just checked with 2 Android phones of mine - they keep the same MAC between reboots - which is as intended.

If yours changes, then its really really weird - and what protections are there to make sure no 2 devices on the same LAN have the same MAC?

MACs on servers are often used to bind licenses too - and while it's possible to change a MAC it's really not "the done thing"....

Gordon

Also if MACs can be changed that easily by the OS/software it explains how hackers manage MAC spoofing. That happened to me once; somebody spoofed the MAC address of my cablemodem and I got an email from my ISP alleging I'd been sending spam email. I rang them and spoke to a Senior Tech who checked my record and found /two/ IP addresses - one of which wasn't even within their range - linked to my MAC address. Unfortunately this was before they supplied them and it was my own property. The manufacturer wouldn't cooperate with my enquiry regarding if it was possible to change the MAC address despite my offering to pay them to do it. I ended up having to accept the ISP's - inferior - modem and with a useless brick as the MAC was then blacklisted.

Julian

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