Cost per prefix [was: request for help w/ ATT and terminology]

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1

> For example, the Cisco 3750G has all of features except for the
> ability to hold 300k+ prefixes. Per CDW, the 48-port version costs
> $10k, so the difference (ergo cost attributable to prefix count) is
> $40k-$10k=$30k, or 75%.

Unfortunately, I have to run real packets through a real router in the
real world, not design a network off CDW's website.

As a simple for-instance, taking just a few thousand routes on the
3750 and trying to do multipath over, say 4xGigE, the 'router' will
fail and you will see up to 50% packet loss. This is not something I
got off CDW's website, this is something we saw in production.

And that's without ACLs, NetFlow, 100s of peering sessions, etc. None
of which the 3750 can do and still pass gigabits of traffic through a
layer 3 decision matrix.

Patrick,

Please excuse me for asking, but you seem to be arguing in a most unusual
manner. You seem to be saying that the 3750 is not a workable device for
L3 routing (which may simply be a firmware issue, don't know, don't care).

From the point of finding a 48-port device which could conceivably route

packets at wirespeed, even if it doesn't /actually/ do so, this device
seems like a reasonable choice for purposes of cost comparisons to me.
But okay, we'll go your way for a bit.

Given that the 3750 is not acceptable, then what exactly would you propose
for a 48 port multigigabit router, capable of wirespeed, that does /not/
hold a 300K+ prefix table? All we need is a model number and a price, and
then we can substitute it into the pricing questions previously posed.

If you disagree that the 7600/3bxl is a good choice for the fully-capable
router, feel free to change that too. I don't really care, I just want to
see the cost difference between DFZ-capable and non-DFZ-capable on stuff
that have similar features in other ways.

... JG

2

If using the 7600/3bxl as the cost basis of "the upgrade", you might as well compare it to the 6500/7600/sup2 or sup3b. Either of these would likely be what people buying the 3bxls are upgrading from, in some cases just because of DFZ growth/bloat, in others, to get additional features (IPv6).

3

Hi Jon,

Hmm. Well, the secondary market is flooded with sup2's right now, with
the card at sub-$1k prices and with a 6500+sup2 in the $5k range.
There isn't really a comparable availability of the sup720-3bxl
although eBay does have a few listed in the $12k range. If we take
$5k-$1k=$4k for the chassis/ps/etc and compare $16k versus $5k for a
6500/sup720-3bxl versus a 6500/sup2 we get just shy of 70%
attributable to the prefix carrying capacity. That's essentially the
same number I came up with before.

I wouldn't want to stand behind those numbers, though. I'm not sure
what the error band is, but it has to be huge. The equivalence in the
secondary market just isn't there. Nor can we use $12k as the baseline
price for the sup720-3bxl. There isn't wide availability at that
price, just a few sketchy sellers from Hong Kong.

Regards,
Bill Herrin

4

Hmm. Well, the secondary market is flooded with sup2's right now, with
the card at sub-$1k prices and with a 6500+sup2 in the $5k range.
There isn't really a comparable availability of the sup720-3bxl
although eBay does have a few listed in the $12k range. If we take

I started to get into this in the last message and decided not to...but another problem with these comparisons is the 'going rate' for Sup2s
is very likely depressed considerably due to their no longer being suitable for full BGP table applications. Go back a couple years, and they were quite a bit more $...probably closer to $10k.

Another is that networks having to upgrade now already bought whatever they're upgrading from (i.e. Sup2s) some time ago at prices similar to what the 3bxls go for now. So they're not just having to spend more or the difference...they're having to nearly double their investment in full table routers (some parts such as the chassis and line cards will likely remain in service).

I wouldn't want to stand behind those numbers, though. I'm not sure
what the error band is, but it has to be huge. The equivalence in the
secondary market just isn't there. Nor can we use $12k as the baseline
price for the sup720-3bxl. There isn't wide availability at that
price, just a few sketchy sellers from Hong Kong.

I wonder if those are being faked yet?

Is there really any point in trying to put a $ figure on each route? Common sense should tell us that polluting the DFZ will eventually cost every network wanting/needing to participate real money (thousands for smaller networks, hundreds of thousands or millions for larger networks/backbones)...so we really ought to be putting effort into education rather than crunching theoretical numbers to determine exactly how many french fries each route equates to.

I know from past experience, that ARIN can step in and 'use their influence' to get transit providers to not accept routes they don't think an ASN should be announcing (acquisition that went way south). I don't know what sort of yearly cash flow surpluses the other RIRs have, but IIRC ARIN is doing quite well. The stats I have from last September suggest the 'ARIN region' is the worst as far as longer than RIR minimum routes being announced. Perhaps ARIN could task one or more people with examining the ARIN portion of the DFZ, and contacting the networks announcing unnecessary deaggregates and when necessary their transit providers, for the purpose of educating and when necessary, leaning on them to clean up their configs. Actually, there are already people doing the first part of that job for free...so all ARIN would have to do is accept & check data that's already been researched and pluck the ARIN member networks from it.

I know, BGP Police is not part of ARIN's mission...but they have the $ to put people on the job and the influence to perhaps get people to pay attention. In my limited experience trying that role, I found networks were totally uninterested in cleaning up and it wasn't even possible to get directly in touch with someone who'd understand the issue much less have access to do anything about it.