[c-nsp] OT - BGP Analysis

[Justin M. Streiner]

On Mon, 16 Oct 2006, Paul Stewart wrote:

> Does anyone know of any tools that would allow us to analyse our BGP
> traffic to answer the question of "if we switched to Provider X and we
> kept Provider Y & Z, X Mb/s of traffic would flow via Provider X" ??

Any commercial products I've seen come with that commercial price tag, as 
you've already seen.  There are freeware tools that will accept Netflow 
data from your border routers and produce nice graphs of traffic by 
protocol, destination, etc.  Some also let you produce reports based on 
some subset of your existing netflow data.  Some of the better / more 
widely used freeware Netflow tools are (in no special order):
* nfsen / nfdump
* flow-tools
* FlowScan
* Stager

A nice list of Netflow tools can be found here:
http://www.switch.ch/tf-tant/floma/software.html

The other thing to keep in mind is that the exact amount of traffic you 
will send to destination X using path Y is subject to some amount of 
variability, often stemming from topology changes outside of your 
little piece of the Internet that are totally beyond your control.  I'm 
also assuming that you're taking reasonably full BGP feeds from your 
upstreams to allow for more granular control over your routing decisions.

jms