HAT PDA Microserver Instructions (HMI)

Data access, reading or writing data, in a HAT PDA must be permitted by the user. In case one application requires data access to a namespace, it has to explicitly request permission from the user. This mechanism of asking permission from the user is called HAT Microserver Instructions (HMI). It forms a legally binding contract between you, the developer, and your user. In particular, you are requesting data from user's HAT PDA, through what we call a data debit. DataSwift will ensure that the HMI, for your application, is shown and confirmed immediately after creating user’s HAT PDA within your application, so you can then freely write and read from the HAT PDA without creating any further additional burden for the user.

All applications, by default, have read and write access to the specified namespace. If you wish to access other data within the HAT PDA but not within your namespace, an additional data debit/HMI would need to be confirmed with the user.

Different HMI Variants

There are two different services that you can use in conjunction with Frictionless HAT Vending:

  • BaaS (Backend As A Service)
  • DaaS (Data As A Service)

Since these 2 services issue HAT PDAs differently, there are some discrepancies in the HMI screens that the users will have to accept.

Please note that in order for users to use your application, they have to agree to the HMI screen, regardless if the application is using BaaS or DaaS.

HMI with BaaS

There are 2 versions of the HMI screen of a new HAT PDA using Baas:

  • Simple HMI
  • HMI with Data debit

The main difference is that the second HMI screen has a data debit embedded.

The simple HMI screen looks like the following image:

Simple HMI This HMI screen will be used for the cases where the application does not require access to a different namespace, or a data debit.

In case the app requires access to a different namespace, or includes a data debit, the following screen will be shown to the user:

HMI with Data debit

HMI with DaaS

For applications using DaaS there is only one HMI screen. Users will be presented with the following screen: