23 Feb
2012
23 Feb
'12
12:12 a.m.
On 2/22/12 7:54 PM, Brian Kantor wrote:
Subnetting is reasonable to do but we still have to
assign addresses in
those subnets one at a time in order to get DNS entries for them and to
enable them in the Internet ingress filter.
I understand the intent ... but as Jay WB8TKL pointed out there are lots
of assignments that have no DNS (or listing in amprhosts).
The division of the AMPRNet space into the existing
blocks of addresses
was primarily for administrative convenience, not as a mandated subnetting
scheme.
Subnets should probably track routers/gateways; that is, each
router/gateway should have a small subnet associated with it. That would
help to keep the routing table at a reasonable size. Since routers often
serve a specific geographical area, having regional subnets could be a fairly
good way to assign addresses.
The hard question is what size region and what size subnet?
At present (at least per Daniel Curry, new coordinator for my region)
coordinators seem to have been instructed to assign individual
addresses, not subnets, in order to capture per-host domain information.
This causes a problem in that when one goes to register a gateway, the
range of addresses doesn't necessarily fall into a normal power of 2 as
would be expected for a subnet. I don't think there is a lot of
contention for this address space, so you could throw a dart and say
that anyone running a gateway should be assigned a /24 or /26 or such.
But then, there's the challenge of how to get data for DNS and ingress
filtering as you mention.
Perhaps the gateway robot can be modified to expect entries for subnets
and hosts within that subnet, including the desired DNS entry for each
host. Then the operator of the gateway could be responsible for
assigning local addresses, maintaining the DNS entries for each, and
sending those updates via the robot.
73 de WA6NMF