Exchanges are a textbook case of a shared ledger. They have separate systems that must work in sync with very low latency between them: order processing, the ledger (for clearing) and price advertising.

The main advantage of a blockchain is with the ledger price advertising between exchange members comes free.

I guess they can even implement OTC markets between peers, but I am not sure how do they plan to work with dark pools where parties want anonimity. Maybe they will just implement an internal blockchain with APIs for anonymous trading.

well it's distributed, so just caching a DB is a bit of a tricky question. What are you going to be caching in your offline storage?

If you just used flat-file CSVs, and don't want to re-download the entire DB twice a day, you want to now come up with syncing strategies, merging strategies, and probably conflict resolution. If you just have a blockchain, then you get all of this for free (so long as your data fits the blockchain shape).

Though I imagine there's something else that can be used here as well...

Why would you need merging and conflict resolution when there's a single source of truth? All you need is a stream of messages and some way to record them. If you want to distribute them P2P, add some metadata to sort them.

per the article, in the Burma case, you have multiple banking branches with only intermittent internet connections, and therefore want to be able to work offline easily while still querying the (albeit stale) database state.

Streams of messages don't work as well when you're multi-party, and the default state is offline, not online

In what way do stream of messages which are recorded by the receiver not work in this case, and how does the Blockchain differ?

> Though I imagine there's something else that can be used here as well...

Running transaction logs; you don't need to re download the entire DB twice a day. If you are disconnected, when you reconnect you give the last sequence number received. It is already built into FIX and other systems. Disconnects happen all the time in real trading systems and the ability to query past transactions doesn't go down.

That something else is called rsync.