nanog mailing list archives
RE: It's Ars Tech's turn to bang the IPv4 exhaustion drum
From: "TJ" <trejrco () gmail com>
Date: Tue, 19 Aug 2008 14:28:00 -0400
-----Original Message-----On Tue, 19 Aug 2008, michael.dillon () bt com wrote:I don't have a problem with assigning customers a /64 of v6 space.Why so little? Normally customers get a /48 except for residential customers who can be given a /56 if you want to keep track of different block sizes. If ARIN will give you a /48 for every customer, then why be miserly with addresses?I don't operate an ISP network (not anymore, anyway...). My customers are departments within my organization, so a /64 per department/VLAN is more sane/reasonable for my environment.Uh, the lower 64 bits of an IP6 address aren't used for routing you know? They're essentially the mac address, or some other sort of autoconf'd host identifier. Last I heard, the smallest allocation is supposed to be a /48 -- I hadn't heard of the /56 thing that Michael was speaking of, though I'm not surprised. There's 64 bits for routing... no need to be so stingy :)64 bits is not a magical boundary. 112 bits is widely recommended for linknets, for example. 64 bits is common, because of EUI-64 and friends. That's it. There is nothing, anywhere, that says that the first 64 bits is for
routing. Just to be clear - this http://tools.ietf.org/html/rfc4291#section-2.5.4 does say: " All Global Unicast addresses other than those that start with binary 000 have a 64-bit interface ID field (i.e., n + m = 64), formatted as described in Section 2.5.1. Global Unicast addresses that start with binary 000 have no such constraint on the size or structure of the interface ID field." (And again - this is a case where the real world and the IETF may not agree 100% ...) /TJ
Current thread:
- RE: It's Ars Tech's turn to bang the IPv4 exhaustion drum, (continued)
- RE: It's Ars Tech's turn to bang the IPv4 exhaustion drum Justin M. Streiner (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Michael Thomas (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Randy Bush (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Nathan Ward (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Alain Durand (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Randy Bush (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Kevin Loch (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Iljitsch van Beijnum (Aug 20)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Sam Stickland (Aug 21)
- RE: It's Ars Tech's turn to bang the IPv4 exhaustion drum Miya Kohno (Aug 21)
- RE: It's Ars Tech's turn to bang the IPv4 exhaustion drum TJ (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Seth Mattinen (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Tony Finch (Aug 19)
- RE: It's Ars Tech's turn to bang the IPv4 exhaustion drum michael.dillon (Aug 20)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Kevin Oberman (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Alain Durand (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Randy Bush (Aug 19)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Iljitsch van Beijnum (Aug 20)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Crist Clark (Aug 20)
- Re: It's Ars Tech's turn to bang the IPv4 exhaustion drum Iljitsch van Beijnum (Aug 20)