Then why is it that whenever we ask for extra space because of issues like
this (in our case, we'd like to be able to assign /19 blocks for each
larger POP so that it can be independantly routed in the Internet) we get
told, sorry, that's an operational issue, we won't assign space for that.
You know, I've got the same problem. I've been trying to think of a way to
deal with one of my locations slower growth, yet higher profile customers.
I want them to be able to route independantly should the links all go out
between it and my other locales, but it doesn't grow fast enough to keep
up with the others and I can't manage to get it into its own /19 without
having to seal from its block as the time draws near to beg ARIN for more
space.
It might behoove ARIN to allow us /19s for locations like that on a
special request form.
Well, like others have mentioned, there are ways around this, even if they
are a bit sub-optimal. As long as you have at least a /19 total, and you
use the same upstream provider(s) in all of the POPs that this /19 is used
in, you can announce the specifics for each pop along with the /19 in each
of those POPs. This will accomplish several things for you. First of
all, like you said, if you lose all internal connectivity from any of
those POPs, but you still have at least 1 upstream, all of your traffic
will still get to you by following the more specific route. Since the /19
is still being announced, those backbones that filter longer masks will
still send the traffic to your upstream(s) who will have the more specific
routes in their tables and send the traffic in the right direction.
This method, of course, is a bit unfriendly since you're making more
announcements than you would be otherwise.
Brandon Ross Network Engineering 404-815-0770 800-719-4664
Director, Network Engineering, MindSpring Ent., Inc. info@mindspring.com
ICQ: 2269442
Stop Smurf attacks! Configure your router interfaces to block directed
broadcasts. See http://www.quadrunner.com/~chuegen/smurf.cgi for details.
This method, of course, is a bit unfriendly since you're making more
announcements than you would be otherwise.
And if you are using 2 different providers for 2 POPs where the
announcement is split, one POP is hosed.
Actually, if you mean you lost internal connectivity, each pop would be
half hosed as long as you're announcing the /19 in both. In that case it
might be best to just announce the specifics and let the traffic from the
providers that do filter on masks longer than /19 be sub-optimal.
Brandon Ross Network Engineering 404-815-0770 800-719-4664
Director, Network Engineering, MindSpring Ent., Inc. info@mindspring.com
ICQ: 2269442
Stop Smurf attacks! Configure your router interfaces to block directed
broadcasts. See http://www.quadrunner.com/~chuegen/smurf.cgi for details.