[5482] in North American Network Operators' Group
Re: No. of routers carrying full routes?
daemon@ATHENA.MIT.EDU (Alan Hannan)
Sun Oct 20 18:39:07 1996
To: dlc@silcom.com (David Carmean)
Date: Sun, 20 Oct 1996 17:37:47 -0500 (CDT)
Cc: nanog@merit.edu, inet-access@earth.com
In-Reply-To: <199610202208.PAA07406@beach.silcom.com> from "David Carmean" at Oct 20, 96 03:08:15 pm
From: alan@mindvision.com (Alan Hannan)
Reply-To: alan@mindvision.com (Alan Hannan)
Hi David,
> Where can I find/how can one estimate the number of routers carrying
> the full Internet route tables?
I don't know that this information is readily available....
I'd guess there are 10 "Big" ISPs w/ an average of 200 Routers
w/ full tables.
I'd guess there are 100 Medium ISPs w/ an average of 7 Routers w/
full tables.
I'd guess there are 25 Companies w/ an average of 3 Routers w/
full tables.
(200 * 10) + ( 7 * 100) + (25 * 3) = 2775 ~= 3000 Routers
> I need to convince someone that singly-homed customer route flaps/
> withdrawals should *not* propagate beyond our AS. I've found some
> discussion of this in the July NANOG archives, and talk about cisco
> floating statics, etc... and that "one-way" traffic is insignificant.
Uhm, I'm not sure the concensus was that they shouldn't. I
believe most everyone would agree that flaps w/in CIDR blocks
should not propogate, and that people should only announce the
most general network possible.
But, if you've got a customer singly-homed to me, ideally, from an
architecturely scalable point of view, you would do well to static
them to your aggregation/POP router.
However, I'm not sure a quorum agreed that single-homed customers
should show up in backbone tables if their routes are/were down.
There are points to be made both ways, but the BB routing tables
are meant to be a snapshot of the net, and if a vector points to
provider P, and customer C is not reachable there, I don't really
think P should announce such....
> I haven't upgraded to 11.1 yet, but my network
> is simple enough [read: not redundant enough?] that all my customers
> are singly-connected; in that case, statics in my border routers
> pointing to my customer edge-router seems to make fast install moot
> for now.
I assume you're looking forward to dampening? That would be a very
Good Thing. Hopefully you're not running OSPF/EIGRP/RIP w/ a
customer and redistributing, but when you start doing BGP w/
customers (even singly homed ones who migrate address space like
universities and research institutions) you will have a need for
dynamic routes, and it may be that static-ing them is an
administrative headache, with minimal benefit to the
broken^H^H^H^H^H^H limited Cisco 7xx0s....
> Finally, is there a *searchable* archive of NANOG anywhere?
Our benevolent friends at Merit promise it soon...
-alan
