Nathan Ward wrote:
Assuming these providers also buy domestic transit from TelstraClear, AS_PATHs look like: - TelstraClear AUT - APE Orcon AUT Shortest AS_PATH wins.
If they buy it from some other transit provider, who interconnects with TelstraClear: - <transit> TelstraClear AUT - APE Orcon AUT Assuming MED, etc. are the same, the oldest path will be selected. As APE routers get poked from time to time to add prefixes, the <transit> provider is likely to be the more stable.
Oldest path is configurable behavior - many people prefer the more deterministic lowest neighbor ID because it prevents neighbor triggered traffic switches. You're also assuming that all providers use the Route Servers and not bilateral peering; which is a risky assumption.
So overall, based on a few assumptions, TelstraClear wins. It's at this point that I encourage APE/WIX(1) peers to make sure you prefer routes learned over APE/WIX. LOCAL_PREF works well here to avoid AS_PATH length and age issues.
I'd generally assume anyone has a local_pref based on cost: ie: highest local_pref for customer (ie. "getting paid for") prefixes second highest for second lowest cost/efficiency (private peering) third highest for third lowest (public) fourth highest for transit (or other) Which fixes any problems with AS_PATH length. You raise some valid points... except the prefix in question wasn't announced by any peer that I could see in any case, so there was no determination being made.