Bitcoin Forum

What the title says..   ??? ??? ???

That's normal. The from field was only used for (now-deprecated) IP-based transactions. Regular p2p transactions (the only ones used today) can come from many addresses, so there isn't always a good way to display them there.

If you really want to know, you can look up the transaction on blockexplorer.com and you can see which source address(es) it came from.

Thank you so much!
Very helpful.
:)

If you get a bitcoin payment without a label attached it should say "anonymous"  lol

This bitcoin brought to you by 4chan.

Lol

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Moar

So how does one properly transact anonymously, if everyone can track things in blockexplorer?

there is nothing in the block that specifically identifies you and you can use a different bitcoin address for every transaction.

Okay, but your client keeps a record of the addresses you have sent from? And your counter-party client keeps a record of addresses they've received at?

So to prove you transacted with said counter-party, authorities would need access to both to and from clients? (The wallet.dat x2?).

Not necessarily. Say at some point you purchased a DVD from an eCommerce provider who was also selling pirated software and got all his servers seized. In his transaction list would be:

SALE    LEGIT_DVD    25BTC    Your name    Your address     Date/Time

Or whatever, so they know at a given time you sent 25BTC to that provider. They can then look on the block explorer and see a 25BTC transaction at that exact moment from one of your bitcoin addresses to the site's bitcoin address, and "the man" how now tied your real name to your bitcoin address. Now all transactions in the block explorer with that address might as well have your real name.

https://en.bitcoin.it/wiki/Anonymity

* cough! * Fake name!
* cough! * Only use the bitcoin address once!

The Man is now up against plausible deniability - "no, Joe Bloggs doesn't live here. Perhaps they lived here before me? No, I've never heard of "LEGIT_DVD" or this "coinbit" thing. Your search warrant says 'Joe Bloggs'? Well come back with a proper warrant with my name on it and then you can legally execute a search. I'll be happy to let you examine my PC's hard drive if you have a legal search warrant."

Even in a post-widespread-bitcoin-acceptance world you just need to make sure that you use multiple wallets, and the bitcoin wallet The Man catches you with isn't connected to LEGIT_DVD.

Incidentally, would The Man even be able to get a search warrant for a LEGIT_DVD purchase? Maybe in some jurisdictions, but in mine the judge signing the warrant would have to be asleep or incompetent (both possible, I'll admit...)

Absolutely, and if you were using BitCoin for primarily things that could get a search warrant issued, you'd take steps to protect your anonymity. However, BTC is not some currency designed for those kinds of activities any more than Google was designed to promote file sharing by indexing .torrent files. When buying online I generally use my real name (so I can sign for it or have it delivered to work), I HAVE to use my real address (or work address), and the Tor network is too slow to bother with regular purchases.

If at any point in the past or future I wanted to buy the eBook "Is My Wife Cheating On Me" and was worried my political opponents would use it against me, the address I used above could be used to link my BitCoin address to me. And because you have to spend money with the same address with which it was received, it's all too easy to accidently spend money that's tied to your ID.

In other words, have two wallets! One that is ONLY used for anonymous activity.

Back on the original topic...


Ok, but how can you do that programatically? The method "gettransaction" doesn't contain that information (which is coherent with the fact that the sending address doesn't appear in the GUI client). Screen-scraping blockexplorer.com should be considered a last resort :).