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A Day in the Life: The Global BGP Table

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Re: A Day in the Life: The Global BGP Table

#21

Post by benjojo12 »

gjf wrote: post #16
kortilla wrote: post #14

Earlier quoted context omitted.

That seems crazy to me. What guardrails are there against a single hacked router pumping 10000 path changes/sec?

The direct peering to the router is likely going to have a bad time, but route advertisement interval I mention in the article is going to coalesce all of those updates together. Downstream peers would only see the one update every 30 seconds (or so).

Yup, unless that component has been disabled (which is quite rare) or the other side is bird, a bgpd that doesn't buffer anything !

Re: A Day in the Life: The Global BGP Table

#22

Post by chriscjcj »

aspenmayer wrote: post #19
chriscjcj wrote: post #7

25 years ago, I worked for a small ISP (back when there was such a thing.) When I started there, we had one upstream ISP. I was charged with getting us multihomed. I found some tutorials written by Avi Freedman (1). I don't know what I would have done without him. He made an intimidating topic approachable. Thanks to him, I got us a /20 from ARIN and advertised our routes to two different peers. It was fascinating to…

> Avi Somewhat off-topic, I’ve noticed on HN that sometimes comments end with single word on a newline, like you have done here. Did your comment get truncated somehow, or did you mess up a copy/paste, or what? Has anyone else noticed this? Is this a telltale sign of generated comments, or other tool usage? I’ve only noticed this on HN, and maybe Reddit once? It happens somewhat more regularly than I can attribute to…

Interesting. Not sure how that happened. I thought I ended the post with the URL. You may be on to something.

Re: A Day in the Life: The Global BGP Table

#24

Post by UltraSane »

I wrote a python script to extract data from an MRT file containing BGP routes from [1] and importing it into Neo4j for exploration. This file contained about 56 million extremely redundant routes and Neo4j is great for "merging" this type of data.

[1] https://data.ris.ripe.net/rrc00/

Re: A Day in the Life: The Global BGP Table

#27

Post by kortilla »

gjf wrote: post #16
kortilla wrote: post #14

Earlier quoted context omitted.

That seems crazy to me. What guardrails are there against a single hacked router pumping 10000 path changes/sec?

The direct peering to the router is likely going to have a bad time, but route advertisement interval I mention in the article is going to coalesce all of those updates together. Downstream peers would only see the one update every 30 seconds (or so).

That’s only true if they can be coalesced. Even with RPKI an intermediate transit router can path length flap 100,000 routes every 30 second interval.

Depending on the RA interval alone is negligence and if you encountered a small ISP that isn’t dampening your updates directly, their peering session is at risk with any of the major transit providers.

Route dampening guardrails were super common 7 years ago and there isn’t any technological development that fixes what they did so I highly doubt they fell out of favor.

Re: A Day in the Life: The Global BGP Table

#28

Post by kortilla »

benjojo12 wrote: post #21
gjf wrote: post #16

Earlier quoted context omitted.

The direct peering to the router is likely going to have a bad time, but route advertisement interval I mention in the article is going to coalesce all of those updates together. Downstream peers would only see the one update every 30 seconds (or so).

Yup, unless that component has been disabled (which is quite rare) or the other side is bird, a bgpd that doesn't buffer anything !

See my adjacent comment to yours. I would like to see why you think dampening is out of favor. Interval batching is not an equivalent protection. If you were playing BGP battleships you were likely playing at a rate where a single prefix was not updating more than once per minute.

That wouldn’t land in the dampening levels that were normally configured that encountered with all of the transit providers.

Re: A Day in the Life: The Global BGP Table

#29

Post by aspenmayer »

chriscjcj wrote: post #22
aspenmayer wrote: post #19

Earlier quoted context omitted.

> Avi Somewhat off-topic, I’ve noticed on HN that sometimes comments end with single word on a newline, like you have done here. Did your comment get truncated somehow, or did you mess up a copy/paste, or what? Has anyone else noticed this? Is this a telltale sign of generated comments, or other tool usage? I’ve only noticed this on HN, and maybe Reddit once? It happens somewhat more regularly than I can attribute to…

Interesting. Not sure how that happened. I thought I ended the post with the URL. You may be on to something.

I don’t mean to suggest you did anything wrong. If you’re on mobile, perhaps you meant to close the keyboard and hit an autocorrect suggestion instead and didn’t catch it before submission? That seems like the most likely explanation that comes to mind.
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