On 03/16/2010 07:38 AM, Rick Ernst wrote:
Regurgitating the original e-mail for context and follow-up.
General responses (some that didn't make it to the list): - "There really is that much space, don't worry about it." - /48s for those that ask for it is fine, ARIN won't ask unless it's a bigger assignment - /52 (or /56) on smaller assignments for conservation if it makes you feel better - Open question on whether byte/octet-boundary assignment (/56 vs /52) is better for some reason
I haven't seen anything on the general feel for prefix filtering. I've seen discussions from /48 down to /54. Any feel for what the "standard" (widely deployed) IPv6 prefix filter size will be?
I filter at /48. I would consider filtering on something shorter for assignments of /32 or shorter if there were obvious bad behaver's. We do advertise more specific /36s but we also have the covering /32.
Thanks,
On Sat, Mar 13, 2010 at 10:49 PM, Rick Ernst <nanog@shreddedmail.com> wrote:
A couple of different incantations searching the archive didn't enlighten me, and I find it hard to believe this hasn't been discussed. Apologies and a request for pointers if I'm rehashing an old question.
As a small/regional ISP, we got our /32 assigned and it's time to start moving forward (customers are asking for it). New hardware, updated IOS, etc. are in the pipe. Discussions are beginning with our upstream providers for peering. Now, what do we do?
A /48 seems to be the standard end-user/multi-homed customer allocation and is the minimum allocation size from ARIN. A /32 provides 65K /48s so, in theory, we could give each of our customers a /48 and still have room for growth. A /48 also appears to be generally accepted as the the longest prefix allowed through filters (although /49 through /54 are also discussed). Most customers, however, won't be multi-homed.
Partly from an IPv4 scarcity perspective, and partly from general efficiency and thrift, it seems awfully silly to hand out /48s to somebody that may have a handful of servers or a couple of home machines, especially with special addressing like link-local if the hosts are not expected to be internet reachable (back-end servervs, etc).
Based on the above, I'm looking to establish some initial policies to save grief in the future: - /52 allocations to end-users (residential, soho, etc.) - /48 allocations to those that request it - If you are going to multi-home, get your own space
This is obviously a very broad brush and takes an insanely large addressing model and makes it even larger (assigning /52s instead of /48s) but, to me at least, it seems reasonable for a first-pass.
For context/scope, we currently have the equivalent of a bit more than the equivalent of a /16 (IPv4) in use.
Thanks,