DistOS 2021F 2021-11-16

Notes

Lecture 17
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Questions?
 - OceanStore cache encrypted?
 - did anyone actually use pond/oceanstore?
 - why later systems used replication vs erasure codes?
 - was encryption really everywhere, including replicated fragments?
 - search in contents of files?
 - issues with MACs?

Do we have anything like OceanStore today?
 - untrusted cloud infrastructure for storage?
   NOPE
 - while you can encrypt remote data, you have to manually do multi-cloud deployments
   and deal with everyone's APIs
     - well, you could do S3-like things with multiple clouds, keep data encrypted
     - but you're working against how they want you to use the systems

Note that OceanStore has no provisions for search or comparison
 - kind of goes against its design
 - modern work on search, computation on encrypted data, but not practical yet


What distributed computing & storage infrastructure do we have today that is "untrusted"?
 - cryptocurrencies, i.e., blockchain-based systems
 - these are VERY WASTEFUL, but why?

For the rest of this class, we're going to be talking about trust
 - nothing works without some sort of trust
 - the trick is deciding what to trust, making that trustworthy,
   and to make the system fail gracefully when trust is violated

What is trusted in OceanStore?
 - the software!
   - encoding, replicating, encrypting, etc
   - small bug can lead to data loss, privacy breach, really anything
 - and thus, the developers of the software
 - note the design is pretty monolithic, not much room for alternative mechanisms
 - who is responsible for fixing the bugs?  UNCLEAR

Contrast this with Amazon S3
 - bugs will happen, but are you trusting the software or the organization?