Multichain 1.0.2: Attaching files to the blockchain

Question

I have a question regarding Multichain 1.0.2.

I would like to be able to add files to the blockchain only from one specific address. The other addresses can not be possible.

It should be possible to read these attached files by any person.

Does Multichain 1.0.2 offer such functionality?
Are there any restrictions?

Answer 1

Anyone who is able to send a transaction is able to add metadata to that transaction, including sticking a file in that metadata in they really want to. But I presume you mean you want a clearly defined space on the chain where files are placed, and only one party can write to that space. This is easy using streams – create a stream which is permissioned for writing (i.e. not 'open') then give write permissions only to the appropriate address. Anyone subscribed to that stream will see the files within, and they will all be added from that address.

Comments

Thank you very much for your answer. There is no method to protect blockchain from adding "trash" to different streams? I understand that you can add a fee (built-in cryptocurrency) for the transaction (and its size) but that does not solve the problem. Someone can add unnecessary data (spammers) to the blockchain. Blockchain can quickly have size TB, which will kill a specific project. There is no way?

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Since this is a decentralized database, there are only two ways to prevent spam:

1. Use a transaction fee in units of the native currency, so that it costs money to spam. This can be done with MultiChain as-is.

2. Implement some policy by all the miners to prevent too many transactions from any particular source. This would require a change to MultiChain's source code.