Maintainer(s): Philip Robinson
Copyright 2019 The Tari Development Community
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The aim of this Request for Comment (RFC) is to describe the process in which an Asset Issuer (AI) will need to engage to register a Digital Asset (DA) and commence its operation on the Digital Asset Network (DAN).
- RFC-0311: Digital Asset Templates
- RFC-0302: Validator Nodes
- RFC-0304: Validator Node Committee Selection
- RFC-0220: Asset Checkpoints
This document will describe the process through which an AI will go in order to:
- register a DA on the base layer;
- assemble a committee of Validator Nodes (VNs); and
- commence operation of the DA on the DAN.
The first step in registering and commencing the operation of an asset is that the AI MUST issue an asset creation transaction to the base layer.
This transaction will be time-locked for the length of the desired nomination period. This ensures that this transaction
cannot be spent until the nomination period has elapsed so that it is present during the entire nomination process. The
value of the transaction will be the
asset_creation_fee described in RFC-0311. The AI
will spend the transaction back to themselves, but locking this fee up at this stage achieves two goals:
Firstly, it makes it expensive to spam the network with asset creation transactions that a malicious AI does not intend to complete.
Secondly, it proves to the VNs that participate in the nomination process that the AI does indeed have the funds required to commence operation of the asset once the committee has been selected.
If the asset registration process fails, e.g. if there are not enough available VNs for the committee, then the AI can refund the fee to themselves after the time lock expires.
The transaction will contain the following extra metadata to facilitate the registration process:
The value of the transaction in clear text and the public spending key of the commitment so that it can be verified by third parties. A third party can verify the value of the commitment by using the information in (1) and (2) below, to calculate (3):
- The output commitment is $ C = k \cdot G + v \cdot H $.
- $ v $ and $ k \cdot G $ are provided in the metadata.
- A verifier can calculate $ C - k \cdot G = v \cdot H $ and verify this value by multiplying the clear text $ v $ by $ H $ themselves.
A commitment (hash) to the asset parameters as defined by a DigitalAssetTemplate described in RFC-0311. This template will define all the parameters of the asset that the AI intends to register, including information the VNs need to know, such as what AssetCollateral is required to be part of the committee.
Once this transaction has been confirmed to the required depth on the blockchain, the nomination phase can begin.
The next step in registering an asset is for the AI to select a committee of VNs to manage the asset. The process to do
this is described in RFC-0304. This process lasts as long as the time lock on the asset
creation transaction described above. The VNs have until that time lock elapses to nominate themselves (in the case of
an asset being registered using the
committee_mode::PUBLIC_NOMINATION parameter in the DigitalAssetTemplate).
Once the nomination phase is complete and the AI has selected a committee as described in RFC-0304,
the chosen committee and AI are ready to commit their
asset_creation_fee and AssetCollaterals to commence the
operation of the asset. This is done by the AI and the committee members collaborating to build the initial Checkpoint
of the asset. When this Checkpoint transaction is published to the base layer, the digital asset will be live on
the DAN. The Checkpoint transaction is described in RFC_0220.