I attended a webinar - Building Directory Services for IRM earlier this week. The presenter is non other than a good friend of mine - Ludovic, Product Manager for ForgeRock OpenDJ.
And I always like this slide from him. It's cool!
The "ferris-wheel" thingy is actually a visual representation of OpenDJ replication topology. It was generated by a script written by Chris Ridd last year - see OpenDJ: Visualizing the Replication Topology.
So, the above topology is configured as such:
1. 4 data-centers across the globe
2. 2 OpenDJ replication servers in each data-center
3. 12-15 OpenDJ directory servers connected to each OpenDJ replication server
4. Total of 200 OpenDJ directory servers deployed
5. 100+ millions entries! Wow!
By the way, this topology is from an actual customer deployment. Yes, it's LIVE in production.
Now, this is indeed Internet Scale.