Bruce Lowekamp (Principal Architect for Skype’s Cloud Infrastructure) did a talk yesterday on Skype’s migration from P2P to a centrally-stored service.
If you’re at all interested in how Skype P2P worked, or how they completely changed the service without any interruption, it’s definitely worth a watch/listen. Also there’s discussion about how they experiment with everyone using Skype and how that data is interpreted and used.
Here are a few notes I made:
- The old Skype P2P network is still up, but will be shutdown in Fall 2018.
- The old Skype P2P clients could operate on their own after login. If they wanted to upgrade the Skype backend database, they would shut it down for 20 minutes as the clients could operate without it. I think I remember experiencing this more than once myself.
- The migration of Skype chat’s protocols are: P2P -> P2P + Griffin -> Messenger -> New Chat Service
For those who were claiming the MSNP is going to continue, I really doubt “New Chat Service” is that.
- The migration of Skype contacts backends are: CBL -> JCS -> ABCH -> PCS -> EXO.
CBL/JCS is Skype’s own contacts, ABCH was the Messenger/Hotmail contacts store. Apparently when they were “75% done” with the ABCH, Microsoft elected to shut it down, and EXO (Exchange Online, the current one) was not ready, so they created PCS.
- There are “thousands” of configuration options that Skype will configure specifically for your client when you connect.
The idea is that they can experiment with users to determine what settings work best in what configurations, and then after a successful experiment, they can deploy that change to everyone.