Imagine you have a cluster of nodes that is isolated for periods of time from the larger internet. Perhaps it's a remote village that gets visited by a bus every day with a WiFi device and hard drive. Or a Martian colony which doesn't always have a connection to the Earth, and sometimes that connection has to bounce through multiple satellites, complete with delays along the way.
The idea is networks that can't directly connect to the larger pool of peers and must instead go through layers of intermediaries.
How do such networks request hashes? How do they let the intermediate nodes (lets call them brokers) know that they'll still be interested in those hashes in an hour, when the broker is no longer connected to the requestor, but is connected to the main network where those hashes live? A sort of shopping list of hashes for the trader to pick up when he goes to the big city.
Can IPFS handle such a use case today? Would such a use case be managed within the core IPFS infrastructure, or would this be an extra layer built on top of a basic IPFS node?