Re: [rrg] Geoff Huston's BGP/DFZ research - 300k DFZ prefixes are the tip of the iceberg

[Marshall Eubanks <[e-mail]>]

On Mar 15, 2010, at 1:13 PM, Paul Jakma wrote:

> On Sun, 14 Mar 2010, Tony Li wrote:
>
>> Actually, no growth in prefixes does not imply that there is no  
>> growth in
>> the Internet.  You can still add customers within existing prefix
>> allocations and improve your addressing efficiency.
>
> Hehe, My implicit assumption is that there's no significant change  
> in allocation densities. :) Stuff like that generally seems to be an  
> administive issue, so it's maybe unlikely it can be affected through  
> routing changes.
>
>> First, no one is claiming that there is an imminent and urgent  
>> problem. What I feel that we've shown is that we have a long term  
>> systemic problem. Given that truly dealing with this issue does  
>> appear to require major amounts of time to deploy, it only seems  
>> reasonable to start dealing with it long before it becomes an  
>> urgent problem.
>
>> Please see my RAWS presentation.  It shows that prefix growth  
>> exceeds the speedup that we can expect in DRAM.
>
> I remember reading that.
>
>> This in turn implies that BGP will take longer to converge at a  
>> given node when that node has to process the full table.
>
> That's the thing though, the most recent data doesn't seem to show  
> any evidence of things like that. If per-node convergence was taking  
> significantly longer (in the "scaling badly relative to prefix  
> growth" sense), then Sigma(per-prefix per-node convergence) should  
> be similarly increasing by at least the same amount and BGP  
> observers ought to be able to see that, and so the data should show  
> it.
>
> Yet it doesn't seem to, right?
>

Do you have a write-up of this ?

Regards
Marshall

> Further, even if the growth issues only affected a certain subset of  
> prefixes, surely there'd be "side-band" issues. I.e. processing  
> problems with certain prefixes should adversely affect the  
> processing of other prefixes being processed around the same time.
>
> I'm sorry for being such an arse with my scepticism, and I'll  
> understand if people reply to me as if I'm half-wit, but if scaling  
> is a problem surely it should be apparent in some data somewhere  
> over the last decade+ that people have been worrying about it?  
> Where's the smoking gun graph, based on real data, that shows the  
> scaling problem? I'm somewhat willing to take your word as  
> authoritative, but ideally we'd have graphs :).
>
> I stress again that, despite taking this contrarian view of the  
> scaling problem, I still think the work here is very important!
>
> I just think this question must have a big impact on which classes  
> of solutions are and are not viable.
>
> regards,
> -- 
> Paul Jakma	[e-mail]	Key ID: 64A2FF6A
> Fortune:
> We don't understand the software, and sometimes we don't understand  
> the
> hardware, but we can *___see* the blinking lights!
> _______________________________________________
> rrg mailing list
> [e-mail]
> http://www.irtf.org/mailman/listinfo/rrg
>