On Wed, Nov 14, 2012 at 6:31 PM, Michael Smith <mksm...@mac.com> wrote: > > On Nov 14, 2012, at 1:50 PM, William Herrin <b...@herrin.us> wrote: > >> On Wed, Nov 14, 2012 at 3:10 PM, Michael Smith <mksm...@mac.com> wrote: >>> I guess I'm confused. I have a /32 that I have broken up >>> into /47's for my discrete POP locations. I don't have a >>> network between them, by design. And, I won't >>> announce the /32 covering route because there is >>> no single POP that can take requests for the entire >>> /32 - think regionalized anycast. >>> >>> So, how is it "worse" to announce the deaggregated >>> /47's versus getting a /32 for every POP? In either >>> case, I'm going to put the same number of routes into the DFZ. >> >> If you announce an ISP /32 from each POP (or an end-user /48, /47, >> etc) then I know that a neutral third party has vetted your proposed >> network configuration and confirmed that the routes are disaggregated >> because the network architecture requires it. If you announce a /47 >> from your ISP space, for all I know you're trying to tweak utilization >> on your ISP uplinks. > > Again, I thought the discussion was about PI, not PA. I don't announce any > PA.
Hi Michael, PI and PA terminology is getting to be as obsolete as Class A, B and C. Your IPv6 addresses fall in to one of three categories: "Allocation" from RIR under ISP rules (/32 or more) "Assignment" from RIR under end-user rules (/48 or more) "Reassignment" from ISP (any size) You will find that you can successfully propagate announcements of allocations in units of /32 or shorter, assignments in units of /48 or shorter and reassignments in units of /32 or shorter. Longer prefix announcements won't be rejected by everybody, but they'll be rejected by enough folks to spoil your day. So, regardless of which of the three types of addresses you work with, you should make sure to get enough so that each of your discrete multihomed networks can announce a prefix as big as or bigger than the minimum. And as a purely pragmatic matter, you should never ever try to number a discrete multihomed IPv6 network using a reassignment. Go get an allocation or assignment (as appropriate) from the RIR instead. Regards, Bill Herrin -- William D. Herrin ................ her...@dirtside.com b...@herrin.us 3005 Crane Dr. ...................... Web: <http://bill.herrin.us/> Falls Church, VA 22042-3004
