North American Network Operators Group

Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical

Re: What is the limit? (was RE: multi-homing fixes)

  • From: Sam Thomas
  • Date: Thu Aug 30 06:01:16 2001

On Wed, Aug 29, 2001 at 11:36:03PM -0700, Roeland Meyer wrote:
> |> From: Randy Bush [mailto:[email protected]]
> |> Sent: Wednesday, August 29, 2001 9:18 PM
> |> 
> |> > there would appear to be people who assert its not unafordable to
> |> > compute the routes for the current, and the forseeable network.
> |> 
> |> and there are those of us who think we can probably do so iff we stop
> |> the explosion of /24s.
> Okay, let's get it back out of the realm of opinion and into requirements.
> I'll even go down one step more, to /25. Take the entire IP addr space,
> break it ALL into /25's, times the BGP table entry size, how big is that?
> Could 4GB of RAM do it? How about 8GB? Your average 64-bit processor can
> handle T-Bytes and they are affordable by your average basement dual-homers.
> Also, I just got a price quote for 512MB ECC PC133 DIMMS at $49US, retail.
> Oh yeah, that same processor runs faster than 1 GHz. That's todays
> *computer* technology. Router technology needs to catch up.

using Jonthan Disher's calculation of 155B/route (a check of my local
neighborhood gsr gave ~185B/route, but this is all academic anyway so
we'll use his number since it was first and so folk playing along at home
can have some continuity), i get ~5GB for the whole address space as /25s.
(using 185B/route, it came to just over 8GB). i don't know of any off
the shelf consumer hardware that supports >2GB (i looked, really!), so the
price to stick that $800 ($16 is extremely reasonable shipping cost for 16
memory sticks, see if you can find it ;) of ram on something just went up
an order of magnitude.

> Considering what router vendors charge, with very fat margins, for their
> low-tech routers, affordable tech arguments don't hold water. Routers are
> expensive because someone is stupid enough to pay the prices. We are getting

i guess we're in the wrong business. we should go develop discount routers
using near-current off-the-shelf technology. thinking this through, i'm
already amazed at the lack of glut for discount high-capacity routers.

oops. some folk (like me) actually want the core router to be able to
handle a chassis chock-full-o-oc48s. that'll take a bit of specialized
hardware. oh, and it would be really nice-ah if the router could forward
ip packets amongst those oc48s at something approaching line-rate. that'll
take an industrial strength backplane. not finding too many multi-Gb/s
backplanes on, so guess that will have to be custom built,
and we'll probably have to develop some custom circuitry to handle the
custom backplane as well.

shoot, forgot software. we've run up the cost so much, we'll just drop in
a peecee with a linux kernel and zebra. we won't be able to route packets
through it, though, so i guess we'll have to custom manufacture some other
device to handle the actual packing shuffling. or, we could custom
develop a single unit and some software that runs on it. i'm sure there
are plenty of bgp/mpls/multicast/etc clued programmers willing to work
in our software sweatshop for minimum wage to keep costs low.

so, after all this, how big of a bargain is using that $800 in ram so far?

ok, it's still probably at least a few bucks cheaper than vendor X. let's
go sell it. hah! silly customers want a number to call when it breaks. 
well, it uses cheap off-the-shelf memory and processor, how much can it
really cost to support? we'll get a bunch of unemployed tech support geeks
from one of the many sunk dot-coms, and tout our low time to answer when
$BIGCUST asks about our post-sale support.

since we used commodity hardware (at least ram and processor), we won't
have to stock spares. i'm sure we can trust our customers to buy the
right parts off the shelf at "Bubba's Fine House of PeeCee Hardware".

i've written you a lovely formula for undercutting (yah right) vendor X.
now go do it, and if you're still in business in 2 years call me and i'll
come work for you.

now, would everyone kindly get off the $EXPENSIVE ram from vendor X whine?

> royally ripped off there. Cisco takes special RAM because Cisco designed
> incompatible RAM circuitry so they could charge you more for the Cisco
> label. It also bolsters the FUD-storm and the after-market support vendors.

or, maybe it's because they had the foresight to know that if they used
commodity ram, a bunch of cheapskate morons would be plugging in the cheapest
ram they could find at the saturday morning swapmeet, and making dozens of
"warranty" support calls because the router crashes all the time or half
the packets come through looking like swiss cheese.

if you're not seeing the lesson here, you're probably not running an actual
network and should unsubscribe yourself at least from nanog-post.

> BTW, you really ought to check out that site at

at the edge, for someone wanting non-flavorful ip (no ipv6, no multicast,
no mpls fun) these might work. we'll see how they're doing in a couple years.

Sam Thomas
Geek Mercenary