I'm just not able to wrap my brain around the subnetting that needs to be done on the router. One of the things which has struck me as being fairly insane about current recommended 'best practices' for IPv6 addressing is the practice of wasting huge blocks of addresses on p2p links; even given the gigantic address space, in a world in which every soda-can, every window-blind, and swarms of medical nanobots injected into one's bloodstream will potentially become spimes,
-----Original Message----- From: Roland Dobbins [mailto:rdobbins@arbor.net] On Aug 14, 2009, at 10:31 PM, Chris Gotstein wrote: this just seems grossly short-sighted.
It is all a matter of perspective. If you want to use /126s (or whatever longer-than-64bit-prefix-you-like) that is ~OK - it certainly works! - but you may be complicating your life in the future. It is "your network" - build it however you wish, just be sure of the benefits and drawbacks associated with those choices. (Purely an off-the-top-of-my-head hypothetical: What if PtP links become drastically less common, and you need to re-address your network from ~/126s to /64s because of that? You are causing yourself pain, and for what gain? To conserve a resource that is not (and according to some, will effectively never be) in short supply?) A great counter-point to this is that if you do use /64s (or for that matter - anything shorter than the currently-not-recommended /127s, AFAIK), you should apply ACLs to them to prevent ping-pong. ((FWIW - counting the number of individual address being used is a non-starter ... ~18,000,000,000,000,000,000 addresses on each segment is more than enough for any solution I expect in the relevant future. I am not saying the goal of conservation is bad (e.g. - I like /56s to homes instead of /48s), just trying to keep things in perspective.)) Pick your flavor of answer, and drink heavily. I prefer coffee ... or Vodka. /TJ