It seemed like a decade in the making but has the IPv6 transit between Cogent and Google (via that showed up last fall remained stable? I’d ruled them out on a number of projects for this reason but may reconsider if it has been reliable. Appears HE (ASN6939) is still unreachable though… I feel like less entities are single homed to HE, but it would still be a calculated risk.
I’ve had zero issues reaching Google via Cogent, however Google didn’t pick up transit from Cogent themselves: They got transit from Tata, which makes them reachable via Cogent due to the peering relationship between Cogent and Tata.
HE is the 800-pound gorilla of IPv6. I would be leery of a carrier without reachability to AS6939.
Are we discussing direct connectivity between 15169/174?
or via a third party(ies)? I ask, because i looks like RouteViews has, in:
at last this bit of clues:
BGP4MP_ET|1594784883.404691|A|22.214.171.124|49788|126.96.36.199/17|49788 174 6453 15169|IGP|188.8.131.52|0|0|174:21100 174:22010|NAG||
BGP4MP_ET|1594784883.404691|A|184.108.40.206|49788|220.127.116.11/17|49788 174 6453 15169|IGP|18.104.22.168|0|0|174:21100 174:22010|NAG||
BGP4MP_ET|1594784883.404691|A|22.214.171.124|49788|126.96.36.199/24|49788 174 6453 15169|IGP|188.8.131.52|0|0|174:21100 174:22010|NAG||
BGP4MP_ET|1594784912.621864|A|184.108.40.206|3277|220.127.116.11/24|3277 3267 174 6453 15169|IGP|18.104.22.168|0|0|3277:39710|NAG||
BGP4MP_ET|1594784912.621864|A|22.214.171.124|3277|126.96.36.199/17|3277 3267 174 6453 15169|IGP|188.8.131.52|0|0|3277:39710|NAG||
BGP4MP_ET|1594784912.621864|A|184.108.40.206|3277|220.127.116.11/17|3277 3267 174 6453 15169|IGP|18.104.22.168|0|0|3277:39710|NAG||
I didn’t go digging much more than that, but I bet looking at each day before the 15th July 2020 might tell you when routes started to show up with that type of path.
So, ‘since last july’ I guess is close to the place where 174 started seeing 15169 across alternate paths.