TestNet Request Codes: Share Here!

Just sent you a MobileCoin!

@ruben: What’s funny is that, because of the design of the MobileCoin system, which is so focused on privacy, you won’t have any idea who sent you a payment unless they identify themselves to you as the owner of that payment.

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Just sended you 1 mob!




Thanks :slight_smile:

I just fulfilled this request which was for 0 MobileCoins. It’s interesting that you can send 0, right? As a protocol, MobileCoin never has any idea what the amount is in a transaction, only that it exists in a range of possible values (I think it’s 0 to 2^64 but I’ll have to check with engineering). This is called a “Range Check”. The nodes don’t check that a user is sending 5 MobileCoins or 100 MobileCoins or whatever amount you’re trying to send, the nodes check a mathematical proof that the amount you’re sending is within the acceptable limits of the system.

This is one of the ways MobileCoin protects your privacy. MobileCoin nodes have zero knowledge of the values a user is transacting.


Just send you some MobileCoin!

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Received :sunglasses: :ok_hand: !

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Just fulfilled your request!

Interesting (and novel!).

I came at it with the idea that it would work “just like my [insert name of other consumer payment brand]”. However, the privacy angle means, I need to readjust my understanding of how it could work.

Use case : Anonymous Tip Jar – If I wanted a “tip jar” I would just publish a payment request and have people push as much MOB to it as they would like.

Use case: Paying a vendor’s Invoice – The Vendor sent to me a unique Request for Payment for the amount. – The transaction is anonymous, and if the Request key is securely sent, the “paper trail” is on other systems.

This will open up some really novel use cases. Cool work!

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Anyone else getting a

"Unable to connect to mobilecoind on
Are you sure it is running and accepting connections?

The error was: RpcFailure: 14-UNAVAILABLE failed to connect to all addresses

both for the watcher node as well as the testnet client package?

What version of MacOS are you running?

same error here too. I run testnet on ubuntu 19.04


The vendor invoicing stuff gets to be really interesting. One of the cool features of MobileCoin is that you can create a master key and associate sub-master keys to it. In this way, a single Master key can manage nearly infinite sub-addresses, so you could give every transaction a unique subaddress to bind customers to transactions (but still get fast aggregate statistics across all of your subaddresses).

This solves the problem of how service providers who are ok knowing who all of their customers are (like exchanges) can service MobileCoin users. It does not solve the problem of how service providers who don’t want to know who their customers are but still want to service MobileCoin users (think oblivious transaction recovery).

For that we need new infrastructure…



ubuntu 18.04 LTS (elementary OS 5.1)

Hey @madde - this can happen if you have multiple mobilecoind running at the same time. You might need to kill the other mobilecoind processes (something like killall -9 mobilecoind).