too many variables

Wayne E. Bouchard web at
Thu Aug 9 21:33:09 UTC 2007

On Thu, Aug 09, 2007 at 09:08:05PM +0000, bmanning at wrote:
> On Thu, Aug 09, 2007 at 02:56:31PM -0400, Patrick Giagnocavo wrote:
> > 
> > 
> > On Aug 9, 2007, at 12:21 PM, bmanning at wrote:
> > 
> > >	so putting a stake in the ground, BGP will stop working @ around
> > >	2,500,000 routes - can't converge...  regardless of IPv4 or IPv6.
> > >	unless the CPU's change or the convergence algorithm changes.
> > 
> > That is a pretty big "unless" .
> 	sure... how often do you completely swap out all your router
> 	processors?  anyone running something other than BGP4? (BGP3
> 	and EGP don't count)  

See, thats the whole thing here...

There will always be legacy equipment in the network. There will
always be advances in processors and newer equipment will be able to
handle more.

The REAL question is wether a threshold will be reached for some
popular older equipment before it gets largely cycled out of use.
The odd company having a problem on one or two boxes is no big deal.
Major carrier A having problems in 6 or 12 (or possibly many more)
routers simultaneously is a bit of an issue. Could even cause a
cascade to external nodes as routers die and reload. To an extent,
this can be dealt with through damping and filtering policies but
there will still be a vulnerability. What should be considered is
wether or not the curve of route growth will overtake the curve of
hardware upgrades and increases in overall base levels of processing

My personal oppinion is that it's unlikely. Possible, but unlikely.


Wayne Bouchard
web at
Network Dude

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