On Tue, 26 Oct 2010 12:19:30 -0500 Jack Bates <jba...@brightok.net> wrote:
> On 10/26/2010 12:04 PM, Nick Hilliard wrote: > > In practice, the RIRs are implementing sparse allocation which makes it > > possible to aggregate subsequent allocations. I.e. not as bad as it may > > seem. > > > > Except, if you are given bare minimums, and you are assigning out to > subtending ISPs bare minimums, Why aren't those subtending ISPs getting their own PI (/32s)? > those subtending ISPs will end up with > multiple networks. Some of them are BGP speakers. I can't use sparse > allocation because I was given minimum space and not the HD-Ratio > threshold space. > > > ARIN, RIPE and AfriNIC, for example, allocate on /29 boundaries. So if > > you get an initial allocation of /32, then find you need more, your > > subsequent allocations will be taken from the same /29, allowing > > aggregation up to /29. > > > > My minimum /30 allocation per ARIN met a /27 in HD-Ratio thresholds. To > not be given the threshold space means no reservations for subtending > ISPs, no room for subtending ISPs to grow, and multiple assignments. If > ARIN only does /29 boundaries, I'll also be getting multiple /29's, and > not just working within a /27 per the HD-Ratio guidelines. > > It's the mixed viewpoint that is the problem. HD-Ratio is useless as a > justification and as a metric which promotes route > conservation/aggregation if it is not used for initial allocations. > Initial allocations (including those handed out to subtending ISPs) > should all be as large as the immediate use HD Ratio permits. ie, If you > are immediately assigning X /56 blocks, your assignment should have a > length one less than the highest threshold you crossed. To assign any > less is to constrain the assignments, not allow for growth, and to > increase routing table size. It also circumvents and completely destroys > the concept of HD Ratio (as the initial assignments all are well in > excess of the thresholds for requesting much larger blocks). > > > Jack >
