Bitcoin Forum

Hi,

The wiki has a very nice description of atomic cross-chain trading here https://en.bitcoin.it/wiki/Atomic_cross-chain_trading (https://en.bitcoin.it/wiki/Atomic_cross-chain_trading) and here https://en.bitcoin.it/wiki/Contracts#Example_5:_Trading_across_chains (https://en.bitcoin.it/wiki/Contracts#Example_5:_Trading_across_chains) .

Here is a concise description of what atomic cross-chain trading is:
"The problem of atomic cross-chain trading is one where (at least) two parties, Alice and Bob, own coins in separate cryptocurrencies (e.g. Bitcoin and Litecoin), and want to exchange them without having to trust a third party (centralized exchange)."

I have two questions:
1) Is it already implemented? Is there a website / application / service that helps the two parties to achieve this goal?
2) I'm interested in the first algorithm from https://en.bitcoin.it/wiki/Atomic_cross-chain_trading (https://en.bitcoin.it/wiki/Atomic_cross-chain_trading). The following sentence appears later on: "it depends on transaction replacement which may, or may not be considered standard under current bitcoin protocol rules."
I don't understand that: where does a transaction replacement happen in the first protocol?
As far as I understand, a transaction replacement is the following operation: tx1 with input1 is transmitted to the network, but not yet included in a block. tx2 with input1, but possibly different output or script, and has a newer version. The miners should remove tx1 from their queue in such a scenario.

Thanks!

Bump...

i also would like to know if there is any known implementation of this protocol.