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Duck-Billed Platypus
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Joined: 30 Jun 2003
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Location: Los Angeles, California, United States of America
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 Posted: Tue Oct 19, 2004 2:46 am Post subject: MAC addresses.. |
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is the MAC address like printed on the nic or something? and also how do programs like ifconfig know the mac address? and is there a way to find out my mac address on windows?
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GenKreton
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Joined: 20 Sep 2003
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Location: Cambridge, MA
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| Posted: Tue Oct 19, 2004 3:07 am Post subject: |
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| Duck-Billed Platypus wrote: | | is the MAC address like printed on the nic or something? and also how do programs like ifconfig know the mac address? and is there a way to find out my mac address on windows? |
mac addy in windows is the physical or hardware address, forget which, under the ip address.. The mac address is hardcored into the devices firmware. On windows there are utilities to change it.
Anyone know of a way for linux? |
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kashani
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| Posted: Tue Oct 19, 2004 3:08 am Post subject: |
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Generally the MAC address is in the firmware or something like that. In Windows you can get it by doing ipconfig /all from a command window.
kashani
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Duck-Billed Platypus
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| Posted: Tue Oct 19, 2004 3:44 am Post subject: |
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ok thanks. the comand prompt thing worked.
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Duck-Billed Platypus
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| Posted: Tue Oct 19, 2004 4:02 am Post subject: |
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Do the first and last three set of numbers have some sort of meaning? cause my computer's integrated nic and my sister's computer's integrated nic both have the same first three numbers for their mac addresses.
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Tasslehoff
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Joined: 09 Jul 2003
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Location: BC Canada
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| Posted: Tue Oct 19, 2004 4:35 am Post subject: |
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to change the MAC address in linux:
ifconfig eth0 hw ether MAC_ADDRESS_HERE |
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splooge
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Joined: 30 Aug 2002
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| Posted: Tue Oct 19, 2004 5:11 am Post subject: |
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| Duck-Billed Platypus wrote: | | Do the first and last three set of numbers have some sort of meaning? cause my computer's integrated nic and my sister's computer's integrated nic both have the same first three numbers for their mac addresses. |
Yes. MAC addresses are all supposed to be unique. Network card vendors are given "ranges" of MAC addresses they can assign to their nics. Your and your sisters nics seem to be made by the same manufacturer as they fall in the same range:
123456000000 -> 123456FFFFFF
This is a place where you can enter the first 6 digits of your MAC address to find out the manufacturer: http://standards.ieee.org/regauth/oui/index.shtml
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Duck-Billed Platypus
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| Posted: Tue Oct 19, 2004 5:13 am Post subject: |
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| splooge wrote: | | Duck-Billed Platypus wrote: | | Do the first and last three set of numbers have some sort of meaning? cause my computer's integrated nic and my sister's computer's integrated nic both have the same first three numbers for their mac addresses. |
Yes. MAC addresses are all supposed to be unique. Network card vendors are given "ranges" of MAC addresses they can assign to their nics. Your and your sisters nics seem to be made by the same manufacturer as they fall in the same range:
123456000000 -> 123456FFFFFF
This is a place where you can enter the first 6 digits of your MAC address to find out the manufacturer: http://standards.ieee.org/regauth/oui/index.shtml |
thats interesting how do they know all that?
yeah both are from intel.
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splooge
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| Posted: Tue Oct 19, 2004 5:22 am Post subject: |
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| Duck-Billed Platypus wrote: | | splooge wrote: | | Duck-Billed Platypus wrote: | | Do the first and last three set of numbers have some sort of meaning? cause my computer's integrated nic and my sister's computer's integrated nic both have the same first three numbers for their mac addresses. |
Yes. MAC addresses are all supposed to be unique. Network card vendors are given "ranges" of MAC addresses they can assign to their nics. Your and your sisters nics seem to be made by the same manufacturer as they fall in the same range:
123456000000 -> 123456FFFFFF
This is a place where you can enter the first 6 digits of your MAC address to find out the manufacturer: http://standards.ieee.org/regauth/oui/index.shtml |
thats interesting how do they know all that?
yeah both are from intel. |
Intel -- or any other nic maker -- gets their MAC addresses from a central body. Much like social security numbers, MAC addresses all must be unique. To ensure uniqueness, IANA -- if memory serves -- assigns what vendors are allowed to use what numbers so there can never be any duplicates.
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Duck-Billed Platypus
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| Posted: Tue Oct 19, 2004 5:24 am Post subject: |
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| splooge wrote: | | Intel -- or any other nic maker -- gets their MAC addresses from a central body. Much like social security numbers, MAC addresses all must be unique. To ensure uniqueness, IANA -- if memory serves -- assigns what vendors are allowed to use what numbers so there can never be any duplicates. |
oh ok that explains it..
with ipv6 would mac addresses also be expanded?
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splooge
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| Posted: Tue Oct 19, 2004 5:25 am Post subject: |
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Nope. Those are two different types of addresses. MAC Addresses are physical, and hard-coded into the card. IP addresses are logical, and are assigned by the user.
And to clear things up, it's IEEE that assigns the numbers, not IANA:
| Quote: | | If your firm manufactures or plans to manufacture products using ISO/IEC 8802 standards, you should apply to IEEE for your firm's OUI. The Institute of Electrical and Electronics Engineers, Inc. has been designated by the ISO Council to act as the registration authority for the implementation of International Standards in the ISO/IEC 8802 series. This is the one world-wide source of registered OUIs. For further details contact: |
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Duck-Billed Platypus
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| Posted: Tue Oct 19, 2004 5:29 am Post subject: |
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| splooge wrote: | Nope. Those are two different types of addresses. MAC Addresses are physical, and hard-coded into the card. IP addresses are logical, and are assigned by the user.
And to clear things up, it's IEEE that assigns the numbers, not IANA:
| Quote: | | If your firm manufactures or plans to manufacture products using ISO/IEC 8802 standards, you should apply to IEEE for your firm's OUI. The Institute of Electrical and Electronics Engineers, Inc. has been designated by the ISO Council to act as the registration authority for the implementation of International Standards in the ISO/IEC 8802 series. This is the one world-wide source of registered OUIs. For further details contact: |
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Cause I know ipv6 would expand ip addresses.. and was wondering what happens when they run out of mac addresses..
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kashani
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| Posted: Tue Oct 19, 2004 2:47 pm Post subject: |
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IPv4 is 2^32 or 4,294,967,296
MACs are 2^48 or 281,474,976,710,656
So there are 65,000 times more MAC address than IP's at the moment.
Also MAC addresses don't have to be globally unique, just locally unique. As long as you don't have any duplicate MACs on your local network you'd be fine. Not that I'm suggesting making the MAC address address space smaller.
kashani
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r1k0d3r
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Joined: 19 Oct 2004
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Location: on a radiowave
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| Posted: Thu Oct 21, 2004 1:22 pm Post subject: |
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as requested before, a great tool to manipulate MAC adresses:
#emerge macchanger
simple and straighforward!!
bless |
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