Hi just a quick question, Coinbase provides me with new BTC address every time I try to deposit BTC, what happens if I use one of the old ones? One of the very first ones I've created when first deposited BTC there? Will it work?
short answer: yes, it'll work.
You can re-use your old addresses for as long as you want, there are only 2 downsides:
- it'll reduce your privacy (if you care about this)
- as soon as you spend any of the unspent outputs funding a certain address, the public key will be known to the network... This isn't a huge problem either, but it weakens your security a tiny bit....
If a hacker only knows your address, he has to use your address to calculate your public key, then he has to calculate your private key starting from your public key... If he already knows your public key, he's one step closer to robbing you... This is only a
THEORETICAL problem tough, so far i don't know any instance of people being able to calculate a private key starting from a know public key.