George Bonser wrote: > We have decided to initiate the process of becoming IPv6 capable. We > have requested and received a block of addresses which, after reading > some of the discussion here, I fear may be too small to suit our needs > (a /48). To better understand how to proceed and in an attempt to get > it right (or close to right) the first time, I am soliciting opinions > and comments from other network operators.
Given you topology your direct assignment request should properly reflect the number of sites you expect to need to need to serve. At a /48 per site it starts to look rational. > It appears from earlier discussions on this list that while many > networks will not filter a /48 announcement in their routing tables, > others will. We have data centers and offices in three regions of the > globe; North America, Europe, and Asia/Pacific. We are also multihomed > as well as having some direct peering. I can break my /48 into /56 nets > for each facility. My thought process here being that if I have the > same transit providers at all sites, I can announce the /48 from my > primary location and that would get announced by the transit provider. > They would also accept my more specific routes but not announce them > outside of their AS. So traffic originating outside of my transit > provider would flow toward them following the /48 and they then move the > traffic to the final destination based on the more specific and in the > case the traffic has no more specific route, hand the traffic to my main > location for me to sort out or just black hole it. There are two > problems with this approach. 1: We are unreachable from anyone > filtering a /48 and 2: I could see a situation where traffic crosses the > Pacific, is handed to my transit provider, and then crosses the Pacific > again to get to the destination resulting in poor performance. > > So it now seems to me that maybe a larger block might be the best answer > but being an "end user" the policies seem pretty restrictive on getting > a /32 though I might qualify for several /48 blocks (at least one in > each registry region). So how does one reconcile having a diverse, > multihomed organization on several continents while at the same time > trying to do the right thing, not requesting more resources than we > need, and trying to be friendly to the various networks' operations by > advertizing only what we need to? Is it unreasonable to get separate > /48 blocks for operations in Europe, North America, and Asia or possibly > two for Asia (one in China and one for Asia outside of China)? While > that still won't help us with connectivity from networks filtering > /48's, it might relieve much of the back and forth transit across oceans > to get traffic originating from and destined for the same continent to > stay there. I don't have a problem with regional backhaul tying an > office /56 to a data center announcing a /48 and using that data center > as a communications hub for the region. It also assumes a transit > provider I am paying to haul my traffic will take "more specifics" for > internal use even if they aren't advertizing them. > > I am just trying to minimize the stupidity and barriers to scale on my > side of the equation. > >
