iotsc URI scheme

The iotsc URI schema defines a link to a smart contract, as defined by the IEEE XMPP Interfaces for IoT Harmonization working group. Smart Contracts are both human-readable and machine-readable, and can be used to automate processes across domain barriers, in a legally binding manner.

Creating a Smart Contract

The process of creating a legally binding smart contract follows the following steps (in a simplified overview):

1. First a Smart Contract Templates is proposed by someone, to a Trust Provider. If TAG technologies are used, the Trust Provider would host a TAG Neuron®, that receives the proposal. The template must include:
   • Duration and Archiving times.
   • Visibility settings.
   • Roles of parts.
   • Number of parts required, and allowed for each role.
   • If signatures can be revoked.
   • Parameters and validation rules.
   • Machine-readable content, that can be validated.
   • Localized human-readable texts and descriptions.
2. The operator of the Trust Provider reviews the template proposal, and approves it, if it is consistent and follows the rules and regulations the Trust Provider has defined. If not, the Trust Provider can also reject it, or ignore it.
3. Once a template has been approved, a client with access to the template can request to create a Smart Contract based on the template. This process can be fully automated, as the integrity of the template has been corroborated by the Trust Provider. When a Smart Contract is created from a template, only role assignments and parameter values can be set, and in accordance with definitions in the template. Human-readable sections, role definitions, validation rules, life-cycle parameters, etc., cannot be modified at this stage.
4. The client can then send proposals to sign the contract to different parties, for different roles. When the Smart Contract has received the necessary digital signatures, it becomes immutable (for the duration of the contract) and legally binding.

Both Smart Contract Templates and Smart Contracts receive an ID on the Trust provider of the following format: CONTRACT_ID@DOMAIN, for example: 2c3a9ca6-d8b4-812b-b42a-302f940120fc@legal.lab.tagroot.io.

You can use the LegalLab project to design and create Smart Contract Templates.

Use Cases for the iotsc URI scheme

The iotsc URI scheme can be used to:

• Provide a link to a Smart Contract Template.
• Invite someone to create a Smart Contract, based on a template, with prefilled parameter values the user can fill in.
• Provide a sharable link to a signed Smart Contract, for reference or for other purposes.
• Propose to a user to sign a Smart Contract, as a given Role.

Syntax

In its simples form, the iotsc URI scheme simply links to a Smart Contract or Smart Contract Template. In that case, the syntax is simply iotsc:CONTRACT_ID, as in the following example:

iotsc:2a746d98-27a9-951f-8816-5dce5960eb0d@legal.lab.tagroot.io

As a QR code, this would be encoded as:

You can add query parameters to the URI, using the same syntax as for HTTP-based URIs (including URI-encoding query parameter values), to suggest parameter values, roles and visibility for a new smart contract, or if you’re referring to a contract template.

Visibility

By adding a Visibility query-parameter to the URI, you can set a proposed visbility of a new smart contract based on a template. The following possible values can be used:

Visbility	Meaning
CreatorAndParts	The most restrictive visibility. Only the creator of the smart contract, and any parts signing the contract, can view the contract.
DomainAndParts	Anyone with a Legal ID on the same domain as the one hosting the contract, can view the contract. Any parts signing the contract, even if from other domains, can also view the contract.
Public	The contract is considered public, and can be viewed by anyone that has access to the contract ID. The contract is not searchable however.
PublicSearchable	The most visible option. Not only is the contract viewable by anyone, it is also indexed and can be searched for using a search engine for smart contracts.

Role

You can propose a Role when sending a contract proposal to someone, or publish the link, without having to know the Legal ID that will be used when signing the contract. You do this by appending the Role query parameter to the URI. The value of the Role parameter should be equal to the ID of the role in the smart contract that should be suggested or pre-selected to the user following the link.

Selecting Parts

If you already know who should sign the contract, and what roles they should have, you can specify the role ID as query parameter, with the Legal ID of the part you wish should sign under that role, as value.

Pre-filled values

You can pre-fill parameter entries, by appending query parameters with the corresponding parameter names and values to the URI. The syntax of the parameter value would depend on the data type of the parameter, but follows canonical string representations for the corresponding types.

Example

Following is a more complete example of a iotsc URI, that includes a reference to a contract, suggested visibility, role for the recipient, predefined part selection for automation, as well as some parameter values for parameters of different types. White-space has been added to the example, for readability. A real URI would be a one-line string without white-space.

iotsc:2a746d98-27a9-951f-8816-5dce5960eb0d@legal.lab.tagroot.io?
	Visibility=Public&
	Role=Creator&
	TrustProvider=27c79713-73c1-0f63-b409-429bb8ff83a2@legal.tagroot.io&
	ClientId=a04533fc-13f0-4ca5-8b76-ed1bc625715d&
	Title=Test&
	Description=Lorem%20Ipsum&
	Value=340&
	Currency=EUR&
	CommissionPercent=10&
	Expires=2022-09-01

The QR-code for this example would be:

#uri, #scheme, #iotsc