can i use MAC as unique identifire

hello frnd,
can i use N/W adaptor MAC as unique identifire, i heard that it is unique and does not change...
can MAC change if i reinstall my OS

is it safe to use the MAC...


thankx in advance
koolprasad2003:)

A components MAC address is unique and static so it will not change, even if you reinstall your OS.

I think the answer is yes but it is possible to spoof MAC addresses see this thread: http://www.vbforums.com/showthread.p...ht=mac+address

mac addresses are unique (usually! Repeats have been known to happen) but don't assume that a client's computer has one. Not every computer has internet or an ethernet port If you read the mac address of a computer without one, you get a different number every time.

MAC addresses of Ethernet adapters are most certainly not unique.

Most network cards arrive with a built-in default value that incorporates a subvalue assigned to the manufacturer, and another subfield that the manufacturer tries to assign sequential values to. Because MAC addresses need to be unique within a LAN segment, almost all adapters made today allow the user to configure a different one. For modern adapters this is typically changeable through the adapter's Properties in Windows. Older cards used a setup utility to modify the value in NVRAM, or even had jumpers on the card.

In most cases one can consider them reasonably unique but normally you should combine the value with some other one if you want to use it for... well something besides Ethernet addressing within a segment.