Billing and Payment

In Greenfield, users are required to pay two different types of fees:

• Firstly, every transaction will require gas fees to pay the Greenfield validator to write the metadata on-chain as described in Gas and Fee part.
• Secondly, the SPs charge the users for their storage service. Such payment also happens on the Greenfield.

The storage service fee will be charged on Greenfield in a steam payment style like Superfluid.

Storage Service Fee

There are two kinds of storage service fees in Greenfield: object storage fee and data package fee.

For storage, every object stored on Greenfield is charged at the price calculated by size, replica numbers, a base price ratio, and other parameters. Once the object is stored, the total charge of storage will be mainly only related to time and the base price.

Users are granted a free, time-based quota for downloading data, with each bucket corresponding to a set of their objects. If the quota is exceeded, users can upgrade their data package to obtain additional quota. The price for each data package is fixed for a certain period, during which users will only be charged based on the amount of time they spend downloading and the package price. This charging scheme remains in effect until the user modifies their data package settings.

Payment Account

By default, the object owner's address will be used to pay for the objects it owns. But users can also create multiple "payment accounts" and associate objects to different payment accounts to pay for storage and bandwidth.

The address format of the payment account is the same as normal accounts. It's derived by the hash of the user address and payment account index. However, the payment accounts are actually only logical ones and only exist in the storage payment module. Users can deposit into, withdraw from and query the balance of payment accounts on the Greenfield blockchain, but users cannot use payment accounts to perform staking or other on-chain transactions. Payment accounts can be set as "non-refundable". Users cannot withdraw funds from such payment accounts.

Downgraded service

Once the payment accounts run out of BNB, the objects associated with these payment accounts will suffer from a downgraded service of downloading, i.e. the download speed and connection numbers will be limited. Once the fund is transferred to the payment accounts, the service quality can be resumed right away. If the service is not resumed for a long time, it is the SPs' discretionary decision to clear the data out, in a similar way to how SPs claim to stop services to certain objects. In such a case, the data may be gone from Greenfield completely.

Note

If users fail to renew their subscription in a timely manner, there is a risk of their stored data being permanently deleted.

Trust or Shift

In Greenfield, there is trust between the users and the SPs for data download.

Since downloading bandwidth incurs additional fees and the download journal is not completely stored on the Greenfield blockchain, Storage Providers (SPs) offer an endpoint interface for users to access detailed logs and downloaders' signatures for download billing. If the users and the SPs cannot agree on the bill, users may just select another Primary SP.

For more tech details, please refer to the stream payment module design.