[tor-talk] What are the PPTOR relays?

[Soul Plane]

Last night I noticed my relay path was using two PPTOR relays. I don't know
much about Tor but from what I've read I thought servers that are related
are supposed to identify themselves as such. Just because two servers have
similar names does not mean they are related though. Are those servers all
run by the same person? Is there a way to tell if they are? Is that unusual
or not? Thanks