Paolo Lucente wrote: > On Fri, Dec 18, 2009 at 10:09:32PM -0600, James Hess wrote: >> On Fri, Dec 18, 2009 at 1:24 PM, Jonny Martin <jo...@pch.net> wrote: >> .. >>> modified if need be - to achieve this. ?Mixing billing with the reachability >>> information signalled through BGP just doesn't seem like a good idea. >> Indeed not.. but it might offer one advantage, if it was mandatory >> for any such tarrif/cost to be advertised there to be valid, and in >> the form of an ancillary BGP route attribute, rather than buried in >> some 500,000 page treaty that forces all ISPs to decipher it and >> try to figure out what their liabilities are. >> >> Mainly because it makes any tarrif very visible, and easily understood. >> and offers an easy ability to automatically make decisions like >> discard reachability information that has any billing labels or >> "strings" attached to it, or has a cost greater than $X per million >> packets listed for 'source'... and easily allows an ISP to replace >> the next hop with null when a tarrif option has been listed, or use >> only a route not subject to tarrif. > > I concur. Such visibility is efficient and drives simplification and > automation from a data mining perspective, when analyzing accounting > information. > > In such context, some care is required. Reachability information is > destination based. Mixing accounting (ie. NetFlow) and reachability > (ie. BGP) information is of good value for traffic delivered out of > a routing domain but not for traffic received, ie. reverse reachability > lookups can be a way although they are not truly deterministic due to > routing asymmetries;
deliberate tunning for purposes of TE, use of default. will all contribute to ingress path not resembling egress... > a mix of ingress measurements, lookup maps and > an export protocol supporting L2 information (ie. for same interface, > multiple peers scenarios) give way a better chance to resolve which > neighboring party is pulling which traffic into the observed domain. > > Cheers, > Paolo > >
