nanog mailing list archives
Re: what about 48 bits?
From: "A.B. Jr." <skandor () gmail com>
Date: Mon, 5 Apr 2010 01:17:19 -0300
2010/4/4 Scott Howard <scott () doc net au>
On Sun, Apr 4, 2010 at 1:51 PM, Matthew Kaufman <matthew () matthew at> wrote:http://en.wikipedia.org/wiki/MAC_addressThe IEEE expects the MAC-48 space to be exhausted no sooner than theyear2100[3]; EUI-64s are not expected to run out in the foreseeable future.And this is what happens when you can use 100% of the bits on "endpoint identity" and not waste huge sections of them on the decision bits for "routing topology".Having around 4 orders of magnitude more addresses probably doesn't hurt either... Although even MAC-48 addresses are "wasteful" in that only 1/4 of them are assignable to/by vendors, with the other 3/4 being assigned to multicast and local addresses (the MAC equivalent of RFC1918) Scott.
Wasteful in many ways. While most of end user devices work with temporarily assigned IP addresses, or even with RFC1918 behind a NAT, very humble ethernet devices come from factory with a PERMANENTE unique mac address. And one of those devices are thrown away – let’s say a cell phone with wifi, or a cheap NIC PC card - the mac address is lost forever. Doesn’t this sound not reasonable? A.b. --
Current thread:
- Re: what about 48 bits?, (continued)
- Re: what about 48 bits? Roland Perry (Apr 07)
- Re: what about 48 bits? Joe Greco (Apr 07)
- Hubs on a NIC (was:Re: what about 48 bits?) Lamar Owen (Apr 07)
- Re: Hubs on a NIC (was:Re: what about 48 bits?) Joe Greco (Apr 07)
- Re: Hubs on a NIC (was:Re: what about 48 bits?) Steven Bellovin (Apr 07)
- Re: Hubs on a NIC (was:Re: what about 48 bits?) Joe Greco (Apr 08)
- Re: Hubs on a NIC (was:Re: what about 48 bits?) Roland Perry (Apr 08)
- Re: what about 48 bits? Michael Thomas (Apr 07)
- Re: what about 48 bits? Michael Thomas (Apr 07)
- Re: what about 48 bits? Roland Perry (Apr 08)
- Re: what about 48 bits? A.B. Jr. (Apr 04)
- Re: what about 48 bits? Scott Howard (Apr 04)
- Re: what about 48 bits? Larry Sheldon (Apr 04)
- Re: what about 48 bits? Kevin Oberman (Apr 04)
- Re: what about 48 bits? Valdis . Kletnieks (Apr 05)
- Re: what about 48 bits? Patrick W. Gilmore (Apr 05)
- Re: what about 48 bits? Valdis . Kletnieks (Apr 05)
- Re: what about 48 bits? joel jaeggli (Apr 05)
- Re: what about 48 bits? Jon Lewis (Apr 06)