routing table go boom (was: Re: [c-nsp] DNS amplification)

Tue Mar 19 19:07:44 UTC 2013

[Thanx for changing subject - should have done it myself a couple posts ago.]

Composed on a virtual keyboard, please forgive typos. 

On Mar 19, 2013, at 14:26, Jared Mauch <jared at puck.nether.net> wrote:
> On Mar 19, 2013, at 2:12 PM, Joe Abley <jabley at hopcount.ca> wrote:
> 
>> We've been saying "unconstrained growth bad" for BGP for years. Presumably we're not all insane. Where is the science?
> 
> I think there is a lot of fear around this topic.  I'm waiting to see the great meltdown at 512k fib entries in networks.  We saw the same  at 128k and 256k with some platforms.  The impact on 512k will be just as great if not larger, but also very transient.  

No way we transition to LISP (or anything else) before hitting that wall. So sit back & enjoy the fireworks. My guess is they will be I impressive and short-lived. But I've been wrong before.

> I've observed a great deal of asymmetrical BGP participants in recent years.  They send a set of routes, sometimes small for their own global good, but take only on-net or default routes from their providers.
> 
> There is also the fact that many traffic-engineering techniques are quite coarse due to the protocol design.  The days of using prepending and aggregation/deaggregation are still with us, even when more sophisticated methods (communities, etc..) exist.  I'm starting to decide that the real issue is that most people just can't route (including some major networks).  The system works because the broken part gets greased, but there are a lot of cosmetic and non-cosmetic defects that linger because people don't realize they are there or are a problem.  If you want data on that, including my minimalistic "faux" science, there is plenty to be had.

I'm wondering why that will be any better if we swap out the underlying protocol. It's not like trying something new will -increase- the average clue level of the monkeys banging on keyboards trying to accidentally compose a routing sonnet. 

And up-ending the installed base is almost certainly going to decrease the d(clue)/dt, as well as the second derivative. 

"Never underestimate the power of human stupidity."

Which is all just a fancy way of saying you can't fix people being idiots by changing a protocol, or hardware, or ... well, anything.

-- 
TTFN,
patrick