How to develop an ownership tracking service based on bitcoin blockchain Now I expect to develop an ownership tracking service like Ascribe. I'm planning to develop it as following, however I am not sure whether my plan is correct. Therefore, please let me ask two questions.


Whether the following plan is correct or not.
Do I need to use bitcoind? Is is not enough to only use bitcoin-library(bitcoinjs-lib)?


My plan is following.
 1. Provide a user address and private_key made by bitcoinjs-lib.
 2. When the user upload an item, the item gets a specific ID.
 3. When the user transfer the item to another, the user put the ID of the item into OP_RETURN area(40byte area)
 4. Track the ownership of the item by tracking the specific ID.
There are a lot of different projects that are looking to solve this problem. Almost all of them use something like colored coins to track an asset on the blockchain. Essentially, what your plan is missing are clear rules that prevent double spending.

Check out coinprism.com, colu.co and chromawallet.com for just a few different implementations of what you're trying to do.