BGP Economics ?

Geoff Huston gih at
Sat Apr 7 23:08:57 UTC 2001

>Is this cessation of growth real ? Is this a sign of the recent economic 
>or is there some more technical explanation (such as more aggressive 
>aggregation at Telstra)?

If you look at the view from AS286, KPNQwest, 
(also I've just started up looking as AS286 remotely at you see nothing of this slow down 
that AS1221 sees. INdeed the AS286 view suggests that the underlying 
drivers are HIGHER than the sull FIB tale - compare the green and blue 
curves to the red curve on James Aldridge's AS286 graphs are you reach the 
conclusion that the table is growing _DESPITE_ recent reffects to improve 
aggregation modulo provider policies.

So whats going on? Inside AS1221 there is a fair number of local routes 
(about 22,000 of them). Over the past three months AS1221 been removing 
noise components from the external view of AS1221 (such as removing 
asymmetric satellite services using BGP routing), and the view on these web 
pages reflects the fact that AS1221 is seeing a total route size value 
(round 103,000) which, over the past three months converging on the 
KPNQwest value (99,000). Internally to AS1221 the number of routes remains 
at 120,000 (I've started looking at this internal noise level at

My personal take on a bottom line: every view of the BGP table is relative, 
and changing local circumstances as well as changing global circumstances 
generate changes in the local perspective of the BGP table. Its sometimes a 
little harder to work out if the local changes reflect some global trend, 
or are just local changes. That's why multiple views in multiple locations 
help _a lot_ in working out the difference between global and local trends. 
In this case it really does appear to be just local issues.

So, if there is a belief that BGP table growth has slowed down in the first 
three months of this year due to social pressure, I do not support such a 
view even though the AS1221 data appears to indicate this. Its just local 
issues. The AS286 view supports the view that the underlying growth drivers 
are as strong as ever and the various efforts of nag mail of network 
operators has been largely (and predictably) ineffectual.

At 4/8/01 08:16 AM, Marshall Eubanks wrote:
>Dear Geoff;
>    I just noticed the remarkable flattening in the recent growth of the 
> BGP table
>in your BGP graphs at :
>It didn't even seem this striking at Minneapolis.
>                                    Regards
>                                    Marshall Eubanks
>    Multicast Technologies, Inc.
>    10301 Democracy Lane, Suite 410
>    Fairfax, Virginia 22030
>    Phone : 703-293-9624          Fax     : 703-293-9609
>    e-mail : tme at
>  Test your network for multicast :

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