RE: multi-homing fixes

From: David Schwartz [mailto:davids@webmaster.com]
Sent: Monday, August 27, 2001 8:52 PM

Patrick Greenwell wrote:

> Please explain why the "basement dual-homer" should not
have the same
> right to diversity as the "major services."
>
> And please, be specific.

  The quesetion is bogus, there is no such thing as a
right to have a route
in my router without paying me for it.

If I am paying for those routes then I have a contractual right. If you
don't want my redundant feed, and the route advertisements that go with it,
then don't take my money.

No one is advocating multi-homing without payment. Where did you read that?

If I choose to extend
that privilege
to people who meet certain minimum requirements because I believe the
benefits will outweight the costs, then that's *my* right.

Please detail the exact costs of a, BGP inserted, routing table entry. Is
it, maybe, 50 cents? Now, how much are you getting for a DS1 link? What does
that cost, exactly, considering that an outfit capable of setting up
multi-homing are probably the folks that your techs never hear from, but
once a year? That appears to be a margin that is far above keystone. How
greedy do you want to be?

All others can
pay me to do it if they want me to. Your rights end at my network.

BTW, randy's position is rather strange, coming from someone that used to
support the FidoNet community, by being the FTSC chair.

If I am paying for those routes then I have a contractual right. If you
don't want my redundant feed, and the route advertisements that go with

it,

then don't take my money.

Please detail the exact costs of a, BGP inserted, routing table entry. Is
it, maybe, 50 cents? Now, how much are you getting for a DS1
link? What does
that cost, exactly, considering that an outfit capable of setting up
multi-homing are probably the folks that your techs never hear from, but
once a year? That appears to be a margin that is far above keystone. How
greedy do you want to be?

  The point you're missing is that the important issue is not whether or not
your ISP will carry and advertise your routes, since you are paying them to.
The important point is whether or not anyone else will carry your route.
There's no reason for a RIR to make a microallocation just so you can
advertise it to your ISP. If the advertisement was purely between
contracually bound parties, the block could be part of a provider's larger
block and there would be no difference. The only reason for a
microallocation is to get a party with whom you do not have a contract to
accept a route that they would not otherwise accept.

  Why else would a multihomer want a microallocation? Why not just use a
chunk of a provider's IP space? The only answers are:

  1) We don't want to be held hostage by a provider. (No good, not a
technical justification.)

  2) We want others to accept our smaller routes. (Why not do it by
contract?)

  DS

>> If I choose to extend
>> that privilege
>> to people who meet certain minimum requirements because I believe the
>> benefits will outweight the costs, then that's *my* right.

Please detail the exact costs of a, BGP inserted, routing table entry. Is
it, maybe, 50 cents? Now, how much are you getting for a DS1 link? What does
that cost, exactly, considering that an outfit capable of setting up
multi-homing are probably the folks that your techs never hear from, but
once a year? That appears to be a margin that is far above keystone. How
greedy do you want to be?

Roeland, I don't think you're following the arguement here. What he was
contending was accepting /24's into his routing tables from the global
routing table that were generated by someone ELSES microsegment BGP
speaking customer.

>> All others can
>> pay me to do it if they want me to. Your rights end at my network.

I agree that nobody has a "right" to have their prefixes listed in my
routing tables unless they're a direct customer of mine. Then again, it
is my obligation to my customers to show them a full view of the net and
if we're talking about microallocations vs someone carving up a CIDR block
and their customers announcing a /24 out of it, I have to accept them to
reach them unless I'm pointing default somewhere. [blah] Small blocks
that are carved out of Carrier-X's /16 and announced as /24's don't
count. They're reachable by the aggregate even if I don't accept the
longer prefix.

So, unless something changes, we'll be accepting /24 and shorter prefixes
from any blocks that the RIRs assign /24's from if we want to provide a
full defaultless view to our customers.

BTW, randy's position is rather strange, coming from someone that used to
support the FidoNet community, by being the FTSC chair.

Politics change. Business models change. Positions change. Not so
strange.

Correct me if I'm wrong, since it's been a few years,
but FidoNet address aggregate quite nicely, don't they?

  --msa

What is the cost of the prefix inserted with causes somebody other's boxes
to crash and burn? The "last" one? We don't know at which point the
network simply passes the threshold of being able to converge faster than
the next update comes. That does not make the cost of every update
pushing the network closer to that point immaterial.

Unlike traffic overload, routing flap overload is _not_ self-correcting.
In fact, given the present technology it is very likely to be
self-amplifying (i suspect that most current BGP implementations in case
of severe overload would simply delay keepalives until peers start
resetting sessions; having BGP to run over strictly serializing transport
(TCP) does not help, either).

The only known non-capital intensive fixes are route aggregation and
intentionally degrading routing system responsiveness (aka flap damping).
Both have severe limitations. When they run out of gas, it's forklift
upgrade to the new generation of routers. Keeping up with Moore's law is
not free.

So far, the current backbone upgrade cycle kept up. Assuming that the
capital cost of the backbone routing equipment installed globally is about
$5bln (this is an out-of-the-blue figure), and it currently works at
design capacity with approx. 100k prefixes, the per-prefix cost of forced
upgrade is about $50k, not including labour costs, and indirect costs of
decreasing network stablility causing customer dissatiscfaction and
resulting in expensive customer churn.

Obviously, not all cost may be attributed to maintaining routing
infrastructure ("traditionally" the upgrades are justified by the need to
maintain competitive backbone speed). Times have changed, though, and
upgrading switching capacity no longer has to be a wholesale box
replacement. Unfortunately, this is not the case with routing update
processing capacity (having parallelized routing stack implementations
helps, but not all that much).

Therefore, the cost of extra prefix is definitely not $0.50; it is _much_
higher.

--vadim

FidoNet address aggregate quite nicely, don't they?

no idea now. but fidonet did fixed four-level hierarchic addresses with
hierarchic source and dest routing in the '80s.

the giggle lesson from fidonet is the big noise about alternate name
spaces. much posturing, amazing egos. no real change or result. no
one was really silly enough to pay attention to the idiots.

randy

To go supremely offtopic..

BTW, randy's position is rather strange, coming from someone that used to
support the FidoNet community, by being the FTSC chair.

When running a FidoNet node you can select what you take and not. Nobody
could demand that you take X or Y although they could strike up agreements
with others to route around you.

In essense, what has changed?