Stealth addresses how does recipient use the bitcoins?

Question

I've been reading on what stealth addresses does:

1. Sender generates unique address using the recipient's stealth address for every transaction
2. If multiple senders send bitcoin to recipient, then blockchain sees sender's addresses going to different random looking addresses

My question is: How does the recipient use the bitcoin he receives? In the recipient wallet, does he have a list of those generated address (made by the sender)? How would he then use those bitcoin without revealing transaction linkability?

Answer 1

How does the recipient use the bitcoin he receives?

Stealth addresses require you to scan all the transactions of the blockchain It is a fairly inefficient process but the stealth address implementations that I've seen have two improvements:

• prefix: each stealth address has a required prefix and you must bruteforce your txid to match the prefix encoded in the stealth address. That way the receiver must only test a subset of transactions.
• dual-key system: a scanning key is introduced to allow the receiver to scan whilst their wallet is locked.

In the recipient wallet, does he have a list of those generated address (made by the sender)?

Yes. A new address is derived from the stealth address and the ephemeral key (provided in the additional output with OP_RETURN). This address is then imported into the wallet.

How would he then use those bitcoin without revealing transaction linkability?

Transaction linkability generally means that you can not link a transaction to a published address (obfuscating the destination). The concept you're aiming at, is transaction traceability (when creating a transaction, how do I obfuscate the source output).

Answer 2

The receiver got to continually scan the entire blockchain to find a match to his/her private keys. Read more: https://www.reddit.com/r/Bitcoin/comments/5xm9bt/what_happened_to_stealth_addresses/