On Thu, Nov 22, 2001 at 07:01:00PM +1300, Andy Linton wrote:
On Wed, 21 Nov 2001, Joe Abley wrote:
There are a few operators who filter on RIR allocation boundaries (Verio is one). However, I would be surprised if 203.0.0.0/10 was treated as anything other than a swamp of /24s, given its history.
But at the most recent IETF in London in August there was a very clear call from the IAB to major providers to start filtering on allocation boundaries.
Which affects real-world operators how, exactly? :)
I would expect that there would be few problems advertising the kind of prefix you are talking about so long as it doesn't have a mask longer than 24 bits. The person to ask about this is your prospective transit provider in NZ, and also any other operator who currently advertises a supernet route which covers the prefix you want to advertise.
I'd want to ask the question why do you (or the customer) want to do this. There may be no problem advertising the /24 today but there may be in the future. Why not use address space from your provider? We all have a responsibility to try to do the 'right thing' with address space. Just because you can do something, doesn't mean you should.
There *are* some legitimate reasons. They could be multi-homing, for example, and trying to avoid the mess of long-prefix prefixes being advertised alongside covering supernets; they could be hosting a prominent nameserver, for which renumbering presents arguably as big a stability threat to the network as the addition of a single prefix in the default-free zone. On the other hand, I have yet to meet a transit provider who would choose idealist conservation of BGP state over customer dollars :)
APNIC have nothing to say about routability of prefixes, in general, just allocation of numbers.
Well not quite - see Policies for address space management in the Asia Pacific region (http://www.apnic.net/docs/policy/add-manage-policy.html) in particular:
6.1. Routability not guaranteed
APNIC recognises that the routability of address space can never be guaranteed. Specifically, in order to reduce the number of globally advertised routes, transit providers worldwide implement route filtering policies based on prefix length, with the result that non-provider-based assignments are least likely to be routable across the Internet. Therefore, APNIC policy should encourage those seeking address space to request it from upstream providers rather than from APNIC directly.
The disclaimer makes lots of sense; APNIC wouldn't want to be sued by an irritated new member who found out that provider Y's policies on the other side of the planet prevented their newly-delegated address block being as reachable as they would like. Still, today it is nobody's business but individual ISPs to dictate what filtering policy should be put in place, and the largest ISPs on the planet do not filter according to RIR allocation boundaries. Joe - To unsubscribe from nznog, send email to majordomo(a)list.waikato.ac.nz where the body of your message reads: unsubscribe nznog