Patent Description:
Decentralized Identifiers (DIDs) are a new type of identifier, which are independent of any centralized registry, identity provider, or certificate authority. Distributed ledger technology (such as blockchain) provides the opportunity for using fully decentralized identifiers. Distributed ledger technology uses globally distributed ledgers to record transactions between two or more parties in a verifiable way. Once a transaction is recorded, the data in the section of the distributed ledger cannot be altered retroactively without the alteration of all subsequent sections of the distributed ledger, which provides a fairly secure platform. In such a decentralized environment, each owner of DID generally has control over his/her own data using his/her DID. The DID owner access the data stored in the personal storage that is associated with the DID via a DID management module, which is a mobile app, a personal computer, a browser, etc..

Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein is practiced. <CIT> describes creating and managing linked decentralized identifiers for an entity. A parent decentralized identifier of an entity has an associated parent private key. A determination is made that a child decentralized identifier is to be created for the parent decentralized identifier. In response to the determination, the parent private key is used to generate a child private key, and a child decentralized identifier is created by at least assigning the generated child private key as the private key for the child decentralized identifier. Each of the decentralized identifiers may be associated with a permission to another entity. The permission associated with the child decentralized identifier may not be broader than the permission granted to the parent decentralized identifier. <NPL>, describes (a) to help readers of the Sovrin Governance Framework (SGF) and its Controlled Documents to understand the meaning of the terms that the authors intended to convey, and (b) to help authors of the SGF-and Domain-Specific Governance Frameworks based on it-to convey such meaning in a consistent fashion. Because the SGF addresses the full spectrum of business, legal, and technical policies for Self-Sovereign Identity, the audience for this Glossary includes business analysts, product managers, lawyers, policymakers, regulators, CIOs, compliance officers, software architects, software developers, and IT professionals. The Glossary includes the level of detail needed to accurately document and administer the Sovrin Governance Framework.

This Summary is provided to introduce a selection of concepts in a simplified form that is further described below in the Detailed Description.

The embodiments described herein are related to delegating a scope of permission between pairwise decentralized identifiers (DIDs). In the decentralized environment, a DID owner can generate and use many different DIDs to communicate with other DID owners. Pairwise DIDs are referred to as a pair of DIDs that are only used for communications between two entities. For example, a first DID owner owns a first DID, and a second DID owner owns a second DID. When the first DID and the second DID are pairwise DIDs, the first DID and the second DID are used only between the first DID owner and the second DID owner. When the first owner is to communicate with a third DID owner, a third DID will be generated and used. Similarly, when the second DID owner is to communicate with the third DID owner, a fourth DID will be generated.

Since the pairwise DIDs are only used between two owners, the relationship between the two owners can often be clearly identified, such as parent-child relationship, employer-employee relationship, customer-service relationship, etc. When a certain relationship exists, one DID owner may want to grant a scope of permission to the other DID owner. For example, a child would likely want to delegate his/her parents a scope of permission to allow the parents to act on behalf of the child.

In a centralized environment, such types of delegation are often performed manually via executing and presenting written agreements to other parties, which is burdensome and prone to fraud. The principles described herein allows various delegations to be securely and automatically executed and validated in a decentralized environment using computing systems and cryptographic technologies.

When a first DID owner delegates a scope of permission to a second DID owner, the first DID owner is a delegator, and the second DID owner is a delegatee. The delegation of a scope of permission from a delegator to a delegatee is likely performed by a computing system that is associated with the delegator (e.g., a management module (e.g., a wallet app), a user agent, and/or an ID hub of the delegator). The computing system first determines a relationship between the owners of the pairwise DIDs. Based on the relationship, the computing system then delegates a scope of permission owned by the delegator DID to the delegatee DID. In particular, the computing system defines the scope of permission, and grants to a public key of the second DID the defined scope of permission. The computing system then generates a signature by a private key of the first DID. The signature proves the delegation of the defined scope of permission to the public key of the second DID. A portion of data related to the delegation is then propagated onto a distributed ledger.

In some embodiments, the computing system further maps a plurality of relationships to a plurality of scope of permissions. The mapping data is recorded in a storage that is accessible by the computing system. Based on the mapping data, the computing system determines the scope of permission corresponding to the relationship between the pairwise DID owners. The mapping of the plurality of relationship to the plurality of scopes of permission is based on (<NUM>) data recorded in DID documents, (<NUM>) data propagated onto the distributed ledger, and/or (<NUM>) user input(s).

In some embodiments, the computing system receives a user input for generating, updating, or deleting a mapped pair of a particular scope of permission and a particular relationship. Based on the user input, the computing system updates the recorded mapping data in the storage. In some cases, in response to the user indication, the computing system also updates delegation(s) between pairwise DIDs that have a particular relationship that is affected by the user input.

The plurality of relationships includes, but are not limited to, (<NUM>) a child-parent relationship, in which the owner of one pairwise DID is a minor child of the owner of the other pairwise DID; (<NUM>) a spousal relationship, in which the owners of the pairwise DIDs are spouses; (<NUM>) an employee-employer relationship, in which the owner of one pairwise DID is an employee of the owner of the other pairwise DID; (<NUM>) a customer-service relationship, in which an owner of one pairwise DID is a customer of the owner of other pairwise DID; or (<NUM>) a contract relationship, in which the owners of the pairwise DIDs are parties to a mutually agreed contract.

Since certain relationships between DID owners may change under various circumstances, in some embodiments, the computing system is caused to automatically update the delegations in response to changes to the relationships. In some cases, in response to a request from the second DID owner of the second DID for access to a scope of permission, the computing system determines whether the particular relationship still exists. Alternatively, or in addition, the computing system periodically checks whether the particular relationship between pairwise DIDs still exists. In some cases, in response to a user input that changes information related to the first DID or information related to the second DID, the computing system determines whether the particular relationship still exists. In response to a determination that the particular relationship no longer exists, the computing system revokes the delegation of the corresponding scope of permission and propagating data related to the revocation of permission to the distributed ledger.

In some embodiments, the defining the scope of permission includes defining one or more restrictions, and the propagating a portion of data related to the delegation includes propagating the one or more restrictions to the distributed ledger. The one or more restrictions include, but are not limited to, (<NUM>) an expiration time of the delegation, (<NUM>) a predetermined number of times that the delegatee is allowed to access a portion of data or service, or (<NUM>) a restriction that restricts the access to a portion of data, such as (i) a read permission, (ii) a write permission, (iii) a delete permission, or (iv) a delegation permission. In some embodiments, the one or more restrictions include one or more conditions, which are required to be satisfied each time the delegatee requests for accessing to the delegated permission. The one or more conditions include, but are not limited to, (i) requiring the delegatee DID to pay a predetermined amount of cryptocurrency, (ii) requiring the delegatee DID to provide one or more verifiable claims, or (iii) requiring the delegatee DID to provide particular personal data, such as (a) an email address, (b) a phone number, (c) a location, (d) a name of the delegatee, (e) an IP address, or (f) a device identifier.

In some embodiments, in response to receiving a request from the second DID owner of the second DID for access to the scope of permission, the computing system requests the second DID (i.e., the computing system associated with the second DID, including a management module, a user agent, or an ID hub of the second DID) for proof of delegation of the scope of permission. The second DID then generates a proof code and sends the proof code to the computing system. The proof code is configured to prove that the second DID has been delegated to the requested scope of permission. The computing system then receives and validates the proof code. Based on the validation result, the computing system grants or denies the request from the second DID.

In some cases, the proof code includes the signature signed by the private key of the first DID. The validating the proof code includes decrypting the signature by a public key of the first DID, and retrieving data related to the delegation from the distributed ledger. The computing system then analyzes the decrypted signature and the data related to the delegation to determine whether the proof code is valid. In some embodiments, the validating the proof code further includes verifying the requested scope of permission is within the delegated scope of permission. When the scope of permission includes one or more conditions, the computing system also determines whether the one or more conditions are satisfied.

Accordingly, the principles described herein allow users (i.e., DID owners) to delegate scopes of permissions to each other or revote previous delegations substantially instantly. Once a scope of permission is delegated, the delegatee can also access the delegated data substantially instantly. As such, the delegations are created and enforced by computing systems of the DID owners, which is advantageous because the traditional requirement for an intermediary or centralized entity for recording or enforcing delegations is eliminated. Further, since there is no centralized entity to record all the data related to the delegation between DID owners, and each pairwise DID is only used to communicate with another DID, the privacy of the DID owners are further protected.

The embodiments described herein are related to delegating a scope of permission between pairwise decentralized identifiers (DIDs). Because the principles described herein is performed in the context of a computing system, some introductory discussion of a computing system will be described with respect to <FIG>. Then, this description will return to the principles of the DID platform with respect to the remaining figures.

In this description and in the claims, the term "computing system" is defined broadly as including any device or system (or a combination thereof) that includes at least one physical and tangible processor, and a physical and tangible memory capable of having thereon computer-executable instructions that are executed by a processor. The memory takes any form and depends on the nature and form of the computing system. A computing system is distributed over a network environment and includes multiple constituent computing systems.

As illustrated in <FIG>, in its most basic configuration, a computing system <NUM> typically includes at least one hardware processing unit <NUM> and memory <NUM>. The processing unit <NUM> includes a general-purpose processor and also includes a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), or any other specialized circuit. The memory <NUM> is physical system memory, which is volatile, non-volatile, or some combination of the two. The term "memory" also be used herein to refer to non-volatile mass storage such as physical storage media. If the computing system is distributed, the processing, memory and/or storage capability is distributed as well.

The computing system <NUM> also has thereon multiple structures often referred to as an "executable component". For instance, memory <NUM> of the computing system <NUM> is illustrated as including executable component <NUM>. The term "executable component" is the name for a structure that is well understood to one of ordinary skill in the art in the field of computing as being a structure that can be software, hardware, or a combination thereof. For instance, when implemented in software, one of ordinary skill in the art would understand that the structure of an executable component include software objects, routines, methods, and so forth, that is executed on the computing system, whether such an executable component exists in the heap of a computing system, or whether the executable component exists on computer-readable storage media.

In such a case, one of ordinary skill in the art will recognize that the structure of the executable component exists on a computer-readable medium such that, when interpreted by one or more processors of a computing system (e.g., by a processor thread), the computing system is caused to perform a function. Such a structure is computer-readable directly by the processors (as is the case if the executable component were binary). Alternatively, the structure is structured to be interpretable and/or compiled (whether in a single stage or in multiple stages) so as to generate such binary that is directly interpretable by the processors. Such an understanding of example structures of an executable component is well within the understanding of one of ordinary skill in the art of computing when using the term "executable component".

The term "executable component" is also well understood by one of ordinary skill as including structures, such as hardcoded or hard-wired logic gates, that are implemented exclusively or near-exclusively in hardware, such as within a field-programmable gate array (FPGA), an application-specific integrated circuit (ASIC), or any other specialized circuit. In this description, the terms "component", "agent", "manager", "service", "engine", "module", "virtual machine" or the like also be used.

For example, such computer-executable instructions are embodied on one or more computer-readable media that form a computer program product. If such acts are implemented exclusively or near-exclusively in hardware, such as within an FPGA or an ASIC, the computer-executable instructions are hardcoded or hard-wired logic gates. The computer-executable instructions (and the manipulated data) is stored in the memory <NUM> of the computing system <NUM>. Computing system <NUM> also contain communication channels <NUM> that allow the computing system <NUM> to communicate with other computing systems over, for example, network <NUM>.

While not all computing systems require a user interface, in some embodiments, the computing system <NUM> includes a user interface system <NUM> for use in interfacing with a user. The user interface system <NUM> includes output mechanisms 112A as well as input mechanisms 112B. The principles described herein are not limited to the precise output mechanisms 112A or input mechanisms 112B as such will depend on the nature of the device. However, output mechanisms 112A might include, for instance, speakers, displays, tactile output, holograms and so forth. Examples of input mechanisms 112B might include, for instance, microphones, touchscreens, holograms, cameras, keyboards, mouse or other pointer input, sensors of any type, and so forth.

Embodiments described herein comprise or utilize a special purpose or general-purpose computing system including computer hardware, such as, for example, one or more processors and system memory, as discussed in greater detail below.

Transmissions media can include a network and/or data links which can be used to carry desired program code means in the form of computer-executable instructions or data structures and which can be accessed by a general-purpose or special-purpose computing system.

Computer-executable instructions comprise, for example, instructions and data which, when executed at a processor, cause a general-purpose computing system, special purpose computing system, or special purpose processing device to perform a certain function or group of functions. Alternatively, or in addition, the computer-executable instructions configure the computing system to perform a certain function or group of functions. The computer executable instructions are, for example, binaries or even instructions that undergo some translation (such as compilation) before direct execution by the processors, such as intermediate format instructions such as assembly language, or even source code.

Those skilled in the art will appreciate that the invention is practiced in network computing environments with many types of computing system configurations, including, personal computers, desktop computers, laptop computers, message processors, hand-held devices, multi-processor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, mobile telephones, PDAs, pagers, routers, switches, data centers, wearables (such as glasses) and the like. In some cases, the invention also is practiced in distributed system environments where local and remote computing systems, which are linked (either by hardwired data links, wireless data links, or by a combination of hardwired and wireless data links) through a network, both perform tasks. In a distributed system environment, program modules are located in both local and remote memory storage devices.

Those skilled in the art will also appreciate that the invention is practiced in a cloud computing environment. Cloud computing environments are distributed, although this is not required. When distributed, cloud computing environments are distributed internationally within an organization and/or have components possessed across multiple organizations.

The remaining figures discuss various computing system which corresponds to the computing system <NUM> previously described. The computing systems of the remaining figures include various components or functional blocks that implement the various embodiments disclosed herein as will be explained. The various components or functional blocks are implemented on a local computing system or are implemented on a distributed computing system that includes elements resident in the cloud or that implement aspects of cloud computing. The various components or functional blocks are implemented as software, hardware, or a combination of software and hardware. The computing systems of the remaining figures include more or less than the components illustrated in the figures and some of the components are combined as circumstances warrant. Although not necessarily illustrated, the various components of the computing systems access and/or utilize a processor and memory, such as processor <NUM> and memory <NUM>, as needed to perform their various functions.

Some introductory discussions of a decentralized identification (DID) and the environment in which they are created and reside will not be given with respect to <FIG>. As illustrated in <FIG>, a DID owner <NUM> owns or controls a DID <NUM> that represents an identity of the DID owner <NUM>. The DID owner <NUM> registers a DID using a creation and registration service, which will be explained in more detail below.

The DID owner <NUM> is any entity that could benefit from a DID. For example, the DID owner <NUM> is a human being or an organization of human beings. Such organizations might include a company, department, government, agency, or any other organization or group of organizations. Each individual human being might have a DID while the organization(s) to which each belongs might likewise have a DID.

The DID owner <NUM> alternatively be a machine, system, or device, or a collection of machine(s), device(s) and/or system(s). In still other embodiments, the DID owner <NUM> is a subpart of a machine, system or device. For instance, a device could be a printed circuit board, where the subpart of that circuit board are individual components of the circuit board. In such embodiments, the machine or device has a DID and each subpart also have a DID. A DID owner might also be a software component such as the executable component <NUM> described above with respect to <FIG>. An example of a complex executable component <NUM> might be an artificial intelligence. An artificial intelligence also owns a DID.

Thus, the DID owner <NUM> is any reasonable entity, human or non-human, that is capable of creating the DID <NUM> or at least having the DID <NUM> created for and associated with them. Although the DID owner <NUM> is shown as having a single DID <NUM>, this need not be the case as there is any number of DIDs associated with the DID owner <NUM> as circumstances warrant.

As mentioned, the DID owner <NUM> creates and registers the DID <NUM>. The DID <NUM> is any identifier that is associated with the DID owner <NUM>. Preferably, that identifier is unique to that DID owner <NUM>, at least within a scope in which the DID is anticipated to be in use. As an example, the identifier is a locally unique identifier, and perhaps more desirably a globally unique identifier for identity systems anticipated to operate globally. In some embodiments, the DID <NUM> is a Uniform Resource Identifier (URI) (such as a Uniform Resource Locator (URL)) or other pointers that relates the DID owner <NUM> to mechanism to engage in trustable interactions with the DID owner <NUM>.

The DID <NUM> is "decentralized" because it does not require a centralized, third party management system for generation, management, or use. Accordingly, the DID <NUM> remains under the control of the DID owner <NUM>. This is different from conventional centralized IDs based trust on centralized authorities and that remain under control of the corporate directory services, certificate authorities, domain name registries, or other centralized authority (referred to collectively as "centralized authorities" herein). Accordingly, the DID <NUM> is any identifier that is under the control of the DID owner <NUM> and independent of any centralized authority.

In some embodiments, the structure of the DID <NUM> is as simple as a username or some other human-understandable term. However, in other embodiments, the DID <NUM> preferably be a random string of numbers and letters for increased security. In one embodiment, the DID <NUM> is a string of <NUM> letters and numbers. Accordingly, the embodiments disclosed herein are not dependent on any specific implementation of the DID <NUM>. In a very simple example, the DID <NUM> is shown as "123ABC".

As also shown in <FIG>, the DID owner <NUM> has control of a private key <NUM> and public key <NUM> pair that are associated with the DID <NUM>. Because the DID <NUM> is independent of any centralized authority, the private key <NUM> should at all times be fully in control of the DID owner <NUM>. That is, the private and public keys should be generated in a decentralized manner that ensures that they remain under the control of the DID owner <NUM>.

As will be described in more detail to follow, the private key <NUM> and public key <NUM> pair is generated on a device controlled by the DID owner <NUM>. The private key <NUM> and public key <NUM> pairs should not be generated on a server controlled by any centralized authority as this causes the private key <NUM> and public key <NUM> pairs to not be fully under the control of the DID owner <NUM> at all times. Although <FIG> and this description have described a private and public key pair, it will also be noted that other types of reasonable cryptographic information and/or mechanism also be used as circumstances warrant.

<FIG> also illustrates a DID document <NUM> that is associated with the DID <NUM>. As will be explained in more detail to follow, the DID document <NUM> is generated at the time that the DID <NUM> is created. In its simplest form, the DID document <NUM> describes how to use the DID <NUM>. Accordingly, the DID document <NUM> includes a reference to the DID <NUM>, which is the DID that is described by the DID document <NUM>. In some embodiments, the DID document <NUM> is implemented according to methods specified by a distributed ledger <NUM> that will be used to store a representation of the DID <NUM> as will be explained in more detail to follow. Thus, the DID document <NUM> has different methods depending on the specific distributed ledger.

The DID document <NUM> also includes the public key <NUM> created by the DID owner <NUM> or some other equivalent cryptographic information. The public key <NUM> is used by third-party entities that are given permission by the DID owner <NUM> to access information and data owned by the DID owner <NUM>. The public key <NUM> also be used by verifying that the DID owner <NUM>, in fact, owns or controls the DID <NUM>.

The DID document <NUM> also includes authentication information <NUM>. The authentication information <NUM> specify one or more mechanisms by which the DID owner <NUM> is able to prove that the DID owner <NUM> owns the DID <NUM>. In other words, the mechanisms of authentication information <NUM> show proof of a binding between the DID <NUM> (and thus it's DID owner <NUM>) and the DID document <NUM>. In one embodiment, the authentication information <NUM> specifies that the public key <NUM> be used in a signature operation to prove the ownership of the DID <NUM>. Alternatively, or in addition, the authentication information <NUM> specifies that the public key <NUM> be used in a biometric operation to prove ownership of the DID <NUM>. Accordingly, the authentication information <NUM> includes any number of mechanisms by which the DID owner <NUM> is able to prove that the DID owner <NUM> owns the DID <NUM>.

The DID document <NUM> also includes authorization information <NUM>. The authorization information <NUM> allows the DID owner <NUM> to authorize third party entities the rights to modify the DID document <NUM> or some part of the document without giving the third party the right to prove ownership of the DID <NUM>. For example, the authorization information <NUM> allows the third party to update any designated set of one or more fields in the DID document <NUM> using any designated update mechanism. Alternatively, the authorization information allows the third party to limit the usages of DID <NUM> by the DID owner <NUM> for a specified time period. This is useful when the DID owner <NUM> is a minor child and the third party is a parent or guardian of the child. The authorization information <NUM> allows the parent or guardian to limit the use of the DID <NUM> until such time as the child is no longer a minor.

The authorization information <NUM> also specifies one or more mechanisms that the third party will need to follow to prove they are authorized to modify the DID document <NUM>. In some embodiments, this mechanism is similar to those discussed previously with respect to the authentication information <NUM>.

The DID document <NUM> also includes one or more service endpoints <NUM>. A service endpoint includes a network address at which a service operates on behalf of the DID owner <NUM>. Examples of specific services include discovery services, social networks, file storage services such as identity servers or hubs, and verifiable claim repository services. Accordingly, the service endpoints <NUM> operate as pointers for the services that operate on behalf of the DID owner <NUM>. These pointers are used by the DID owner <NUM> or by third party entities to access the services that operate on behalf of the DID owner <NUM>. Specific examples of service endpoints <NUM> will be explained in more detail to follow.

The ID document <NUM> further includes identification information <NUM>. The identification information <NUM> includes personally identifiable information such as the name, address, occupation, family members, age, hobbies, interests, or the like of DID owner <NUM>. Accordingly, the identification information <NUM> listed in the DID document <NUM> represents a different persona of the DID owner <NUM> for different purposes. For instance, a persona is pseudo-anonymous, e.g., the DID owner <NUM> include a pen name in the DID document when identifying him or her as a writer posting articles on a blog; a persona is fully anonymous, e.g., the DID owner <NUM> only want to disclose his or her job title or other background data (e.g., a school teacher, an FBI agent, an adult older than <NUM> years old, etc.) but not his or her name in the DID document; and a persona is specific to who the DID owner <NUM> is as an individual, e.g., the DID owner <NUM> includes information identifying him or her as a volunteer for a particular charity organization, an employee of a particular corporation, an award winner of a particular award, etc..

The DID document <NUM> also includes credential information <NUM>, which also be referred to herein as an attestation. The credential information <NUM> is any information that is associated with the DID owner <NUM>'s background. For instance, the credential information <NUM> is (but not limited to) a qualification, an achievement, a government ID, a government right such as a passport or a driver's license, a digital asset provider or bank account, a university degree or other educational history, employment status and history, or any other information about the DID owner <NUM>'s background.

The DID document <NUM> also includes various other information <NUM>. In some embodiments, the other information <NUM> includes metadata specifying when the DID document <NUM> was created and/or when it was last modified. In other embodiments, the other information <NUM> includes cryptographic proofs of the integrity of the DID document <NUM>. In still further embodiments, the other information <NUM> includes additional information that is either specified by the specific method implementing the DID document or desired by the DID owner <NUM>.

<FIG> also illustrates a distributed ledger or blockchain <NUM>. The distributed ledger <NUM> is any decentralized, distributed network that includes various computing systems that are in communication with each other. For example, the distributed ledger <NUM> includes a first distributed computing system <NUM>, a second distributed computing system <NUM>, a third distributed computing system <NUM>, and any number of additional distributed computing systems as illustrated by the ellipses <NUM>. The distributed ledger or blockchain <NUM> operates according to any known standards or methods for distributed ledgers. Examples of conventional distributed ledgers that correspond to the distributed ledger or blockchain <NUM> include, but are not limited to, Bitcoin [BTC], Ethereum, and Litecoin.

In the context of DID <NUM>, the distributed ledger or blockchain <NUM> is used to store a representation of the DID <NUM> that points to the DID document <NUM>. In some embodiments, the DID document <NUM> is stored on the actually distributed ledger. Alternatively, in other embodiments the DID document 210is stored in a data storage (not illustrated) that is associated with the distributed ledger or blockchain <NUM>.

As mentioned, a representation of the DID <NUM> is stored on each distributed computing system of the distributed ledger or blockchain <NUM>. For example, in <FIG> this is shown as the DID has <NUM>, DID has <NUM>, and DID has <NUM>, which are ideally identical copies of the same DID. The DID hash <NUM>, DID hash <NUM>, and DID hash <NUM> then point to the location of the DID document <NUM>. The distributed ledger or blockchain <NUM> also store numerous other representations of other DIDs as illustrated by references <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>.

In one embodiment, when the DID user <NUM> creates the DID <NUM> and the associated DID document <NUM>, the DID has <NUM>, DID has <NUM>, and DID hash <NUM> are written to the distributed ledger or blockchain <NUM>. The distributed ledger or blockchain <NUM> thus records that the DID <NUM> now exists. Since the distributed ledger or blockchain <NUM> is decentralized, the DID <NUM> is not under the control of any entity outside of the DID owner <NUM>. The DID hash <NUM>, DID has <NUM>, and DID has <NUM> includes, in addition to the pointer to the DID document <NUM>, a record or timestamp that specifies when the DID <NUM> was created. At a later date when modifications are made to the DID document <NUM>, this also is recorded in DID has <NUM>, DID has <NUM>, and DID has <NUM>. The DID has <NUM>, DID has <NUM>, and DID hash <NUM> further includes a copy of the public key <NUM> so that the DID <NUM> is cryptographically bound to the DID document <NUM>.

Having described DIDs and how they operate generally with reference to <FIG>, specific embodiments of DIDs will now be explained. Turning to <FIG>, an environment <NUM> that is used to perform various DID lifecycle management operations and services will now be explained. It will be appreciated that the environment of <FIG> reference elements from <FIG> as needed for ease of explanation.

As shown in <FIG>, the environment <NUM> includes various devices and computing systems that are owned or otherwise under the control of the DID owner <NUM>. These include a user device <NUM>. In some cases, the user device <NUM> is a mobile device such as a smartphone, a computing device such as a laptop computer, or any device such as a car or an appliance that includes computing abilities. The device <NUM> includes a web browser <NUM> operating on the device and an operating system <NUM> operating the device. More broadly speaking, the dashed line <NUM> represents that all of these devices are owned or otherwise under the control of the DID owner <NUM>.

The environment <NUM> also includes a DID lifecycle management module <NUM>. Sometimes, the DID lifecycle management module <NUM> also be referred to as a wallet or an agent. It will be noted that in operation, the DID lifecycle management module <NUM> reside on and be executed by one or more of user device <NUM>, web browser <NUM>, and the operating system <NUM> as illustrated by the lines 301a, 302a, and 303a. Accordingly, DID lifecycle management module <NUM> is shown as being separate for ease of explanation.

As shown in <FIG>, the DID lifecycle management module <NUM> includes a DID creation module <NUM>. The DID creation module <NUM> is used by the DID owner <NUM> to create the DID <NUM> or any number of additional DIDs, such as DID <NUM>. In one embodiment, the DID creation module includes or otherwise has access to a User Interface (UI) element <NUM> that guide the DID owner <NUM> in creating the DID <NUM>. The DID creation module <NUM> has one or more drivers that are configured to work with the particular distributed ledgers such as distributed ledger <NUM> so that the DID <NUM> complies with the underlying methods of that distributed ledger.

A specific embodiment will now be described. For example, UI <NUM> provides a prompt for the user to enter a username or some other human recognizable name. This name is used as a display name for the DID <NUM> that will be generated. As previously described, the DID <NUM> is a long string of random numbers and letters and so having a human recognizable name for a display name be advantageous. The DID creation module <NUM> then generates the DID <NUM>. In the embodiments having the UI <NUM>, the DID <NUM> is shown in a listing of identities and is associated with the human recognizable name.

The DID creation module also includes a key generation module <NUM>. The key generation module generates the private key <NUM> and public key <NUM> pairs previously described. The DID creation module <NUM> then uses the DID <NUM> and the private and public key pair to generate the DID document <NUM>.

In operation, the DID creation module <NUM> accesses a registrar <NUM> that is configured to the specific distributed ledger that will be recording the transactions related to the DID <NUM>. The DID creation module <NUM> uses the registrar <NUM> to record the DID hash <NUM>, DID hash <NUM>, and DID hash <NUM> in the distributed ledger in the manner previously described and to store the DID document <NUM> in the manner previously described. This process uses the public key <NUM> in the has generation.

In some embodiments, the DID lifecycle management module <NUM> includes an ownership module <NUM>. The ownership module <NUM> provides mechanisms that ensure that the DID owner <NUM> is aware that the DID owner <NUM> is in sole control of the DID <NUM>. In this way, the provider of the DID lifecycle management module <NUM> is able to ensure that the provider does not control the DID <NUM>, but is only providing the management services.

As previously discussed, the key generation module <NUM> generates the private key <NUM> and public key <NUM> pair and the public key <NUM> is then recorded in the DID document <NUM>. Accordingly, the public key <NUM> is used by all devices associated with the DID owner <NUM> and all third parties that desire to provide services to the DID owner <NUM>. Accordingly, when the DID owner <NUM> desires to associate a new device with the DID <NUM>, the DID owner <NUM> executes the DID creation module <NUM> on the new device. The DID creation module <NUM> then uses the registrar <NUM> to update the DID document <NUM> to reflect that the new device is now associated with the DID <NUM> and this would be reflected in an updated transaction on the distributed ledger <NUM> as previously described.

In some embodiments, however, it is advantageous to have a public key per device <NUM> owned by the DID owner <NUM> as this allows the DID owner <NUM> to sign with the specific device public key without having to access a general public key. In other words, since the DID owner <NUM> will use different devices at different times (for example using a mobile phone in one instance and then using a laptop computer in another instance) it is advantageous to have a key associated with each device to provide efficiencies in signing using the keys. Accordingly, in such embodiments, the key generation module generates additional public keys <NUM> and <NUM> when the additional devices execute the DID creation module <NUM>. These additional public keys are associated with private key <NUM> or in some instances is paired with a new private key.

In those embodiments where the additional public keys <NUM> and <NUM> are associated with different devices, the additional public keys <NUM> and <NUM> are recorded in the DID document <NUM> as being associated with those devices. This is shown in <FIG>. It will be appreciated that the DID documents <NUM> include the information previously described in relation to <FIG> in addition to the information shown in <FIG>. If the DID document <NUM> existed prior to the device-specific public keys being generated, then the DID document <NUM> would be updated by the creation module <NUM> via the registrar <NUM> and this would be reflected in an updated transaction on the distributed ledger <NUM>.

In some embodiments, the DID owner <NUM> can keep the association of a device with a public key or even with the DID <NUM> a secret. Accordingly, the DID creation module <NUM> causes that such data be secretly shown in the DID document <NUM>.

As described thus far, the DID <NUM> has been associated with all the devices under the control of the DID owner <NUM>, even when the devices have their own public keys. However, in some embodiments it is useful for each device or some subset of devices under the control of the DID owner <NUM> to each have their own DID. Thus, in some embodiments the DID creation module <NUM> generates an additional DID, for example, DID <NUM>, for each device. The creation module would then generate private and public key pairs and DID documents for each of the devices and have them recorded on the distributed ledger <NUM> in the manner previously described. Such embodiments are advantageous for devices that change ownership as it is possible to associate the specific device DID to the new owner of the device by granting the new owner authorization rights in the DID document and revoking such rights from the old owner.

As mentioned, the private key, to ensure that it is totally in the control of the DID owner <NUM>, is created on the user device <NUM>, browser <NUM>, or operating system <NUM> owned or controlled by the DID owner <NUM> that executed the DID management module <NUM>. In this way, there is little chance that a third party gains control of the private key <NUM>, especially the provider of the DID lifecycle management module <NUM>. However, there is a chance that the device storing the private key <NUM> is lost by the DID owner <NUM>, which causes the DID owner <NUM> to lose access to the DID <NUM>. Accordingly, in some embodiments, the UI <NUM> includes the option to allow the DID owner <NUM> to export the private key <NUM> to an off device secured database <NUM> that is under the control of the DID owner <NUM>. In some embodiments, the private key <NUM> is stored as a QR code that scanned by the DID owner <NUM>.

In other embodiments, the DID lifecycle management module <NUM> includes a recovery module <NUM> that is used to recover a lost private key <NUM>. In operation, the recovery module <NUM> allows the DID owner <NUM> to select one or more recovery mechanisms <NUM> at the time the DID <NUM> is created that later be used to recover the lost private key. In those embodiments having the UI <NUM>, the UI <NUM> allow the DID owner <NUM> to provide required information that will be needed by the one or more recovery mechanisms <NUM> when the recovery mechanisms are implemented. The recovery module then be run on any device associated with the DID <NUM>.

The DID lifecycle management module <NUM> also includes a revocation module <NUM> that is used to revoke or sever a device from the DID <NUM>. In operation, the revocation module uses the UI element <NUM>, which allows the DID owner <NUM> to indicate a desire to remove a device from being associated with the DID <NUM>. In one embodiment, the revocation module access the DID document <NUM> and causes that all references to the device be removed from the DID document. Alternatively, the public key for the device is removed. This change in the DID document <NUM> then is reflected as an updated transaction on the distributed ledger <NUM> as previously described.

<FIG> illustrates an embodiment of an environment <NUM> in which a DID such as DID <NUM> is utilized. Specifically, the environment <NUM> will be used to describe the use of the DID <NUM> in relation to one or more decentralized personal storages or identity hubs. An identity hub is a storage of attributes, including keys and metadata under the control of the holder of the DID. It will be noted that <FIG> includes references to elements first discussed in relation to <FIG> or <FIG> and thus use the same reference numeral for ease of explanation.

In one embodiment, the identity hubs <NUM> are multiple instances of the same identity hub. This is represented by line 410A. Thus, the various identity hubs <NUM> include at least some of the same data and services. Accordingly, if any change is made to one of the identity hubs <NUM>, the change is reflected in the remaining identity hubs. For example, the first identity hub <NUM> and second identity hub <NUM> are implemented in cloud storage and thus is able to hold a large amount of data. Accordingly, a full set of the data is stored in these identity hubs. However, the identity hubs <NUM> and <NUM> have less memory space. Accordingly, in these identity hubs a descriptor of the data stored in the first and second identity hubs is included. Alternatively, a record of changes made to the data in other identity hubs is included. Thus, changes in one of the identity hubs <NUM> are either fully replicated in the other identity hubs or at least a record or descriptor of that data is recorded in the other identity hubs.

Because the identity hubs are multiple instances of the same identity hub, only a full description of the first identity hub <NUM> will be provided as this description also applies to the identity hubs <NUM>-<NUM>. As illustrated, identity hub <NUM> includes data storage <NUM>. The data storage <NUM> is used to store any type of data that is associated with the DID owner <NUM>. In one embodiment the data is a collection <NUM> of a specific type of data corresponding to a specific protocol. For example, in some cases, collection <NUM> is medical records data that corresponds to a specific protocol for medical data. In some other cases, collection <NUM> is any other type of data.

In one embodiment, the stored data have different authentication and privacy settings <NUM> associated with the stored data. For example, a first subset of the data has a setting <NUM> that allows the data to be publicly exposed, but that does not include any authentication to the DID owner <NUM>. This type of data is for relatively unimportant data such as color schemes and the like. A second subset of the data has a setting <NUM> that allows the data to be publicly exposed and that includes authentication to the DID owner <NUM>. A third subset of the data has a setting <NUM> that encrypts the subset of data with the private key <NUM> and public key <NUM> pair (or some other key pair) associated with the DID owner <NUM>. This type of data will require a party to have access to the public key <NUM> or to some other associated public key in order to decrypt the data. This process also includes authentication to the DID owner <NUM>. A fourth subset of the data has a setting <NUM> that restricts this data to a subset of third parties. This requires that public keys associated with the subset of third parties be used to decrypt the data. For example, the DID owner <NUM> causes the setting <NUM> to specify that only public keys associated with friends of the DID owner <NUM> decrypt this data.

In some embodiments, the identity hub <NUM> has a permissions module <NUM> that allows the DID owner <NUM> to set specific authorization or permissions for third parties such as third parties <NUM> and <NUM> to access the identity hub. For example, the DID owner <NUM> provides access permission to his or her spouse to all the data <NUM>. Alternatively, the DID owner <NUM> allows access to his or her doctor for any medical records. It will be appreciated that the DID owner <NUM> permission to any number of third parties to access a subset of the data <NUM>. This will be explained in more detail to follow.

The identity hub <NUM> also has a messaging module <NUM>. In operation, the messaging module allows the identity hub to receive messages such as requests from parties such as third parties <NUM> and <NUM> to access the data and services of the identity hub. In addition, the messaging module <NUM> allows the identity hub <NUM> to respond to the messages from the third parties and to also communicate with a DID resolver <NUM>. This will be explained in more detail to follow. The ellipses <NUM> represent that the identity hub <NUM> has additional services as circumstances warrant.

In one embodiment, the DID owner <NUM> wish to authenticate a new device <NUM> with the identity hub <NUM> that is already associated with the DID <NUM> in the manner previously described. Accordingly, the DID owner <NUM> utilizes the DID management module <NUM> associated with the new user device <NUM> to send a message to the identity hub <NUM> asserting that the new user device is associated with the DID <NUM> of the DID owner <NUM>.

However, the identity hub <NUM> not initially recognize the new device as being owned by the DID owner <NUM>. Accordingly, the identity hub <NUM> uses the messaging module <NUM> to contact the DID resolver <NUM>. The message sent to the DID resolver <NUM> includes the DID <NUM>.

The DID resolver <NUM> is a service, application, or module that is configured in operation to search the distributed ledger <NUM> for DID documents associated with DIDs. Accordingly, in the embodiment the DID resolver <NUM> search the distributed ledger <NUM> using the DID <NUM>, which result in the DID resolver <NUM> finding the DID document <NUM>. The DID document <NUM> then be provided to the identity hub <NUM>.

As discussed previously, the DID document <NUM> includes a public key <NUM> or <NUM> that is associated with the new user device <NUM>. To verify that the new user device is owned by the DID owner <NUM>, the identity hub <NUM> provides a cryptographic challenge to the new user device <NUM> using the messaging module <NUM>. This cryptographic challenge will be structured such that only a device having access to the private key <NUM> will be able to successfully answer the challenge.

In the embodiment, since the new user device is owned by DID owner <NUM> and thus has access to the private key <NUM>, the challenge is successfully answered. The identity hub <NUM> then records in the permissions <NUM> that the new user device <NUM> is able to access the data and services of the identity hub <NUM> and also the rest of the identity hubs <NUM>.

It will be noted that this process of authenticating the new user device <NUM> was performed without the need for the DID owner <NUM> to provide any username, password or the like to the provider of the identity hub <NUM> (i.e., the first cloud storage provider) before the identity hub <NUM> could be accessed. Rather, the access was determined in a decentralized manner based on the DID <NUM>, the DID document <NUM>, and the associated public and private keys. Since these were at all times in the control of the DID owner <NUM>, the provider of the identity hub <NUM> was not involved and thus has no knowledge of the transaction or of any personal information of the DID owner <NUM>.

In another example embodiment, the DID owner <NUM> provide the DID <NUM> to the third party entity <NUM> so that the third party access data or services stored on the identity hub <NUM>. For example, the DID owner <NUM> is a human who is at a scientific conference who desires to allow the third party <NUM>, who is also a human, access to his or her research data. Accordingly, the DID owner <NUM> provide the DID <NUM> to the third party <NUM>.

Once the third party <NUM> has access to the DID <NUM>, he or she access the DID resolver <NUM> to access the DID document <NUM>. As previously discussed, the DID document <NUM> include an endpoint <NUM> that is an address or pointer to the identity hub <NUM>. The third party <NUM> then use the address or pointer to access the identity hub <NUM>.

The third party <NUM> send a message to the messaging module <NUM> asking for permission to access the research data. The messaging module <NUM> then send a message to the DID owner <NUM> asking if the third party <NUM> should be given access to the research data. Because the DID owner desires to provide access to this data, the DID owner <NUM> allow permission to the third party <NUM> and this permission is recorded in the permissions <NUM>.

The messaging module <NUM> then message the third party <NUM> informing the third party that he or she is able to access the research data. The identity hub <NUM> and the third party <NUM> then directly communicate so that the third party access the data. It will be noted that in many cases, it will actually be an identity hub associated with the third party <NUM> that communicates with the identity hub <NUM>. However, it a device of the third party <NUM> that does the communication.

Advantageously, the above-described process allows the identity hub <NUM> and the third party <NUM> to communicate and to share the data without the need for the third party to access the identity hub <NUM> in a conventional manner. Rather, the communication is provisioned in a decentralized manner using the DID <NUM> and the DID document <NUM>. This advantageously allows the DID owner to be in full control of the process.

As briefly discussed above, the identity hub <NUM> is hosted in a cloud service. The service provider has access to the data stored in each user's identity hub <NUM>. Furthermore, the service provider also has access to certain activities of the DID owner. For example, the entities with whom the DID owner has shared his/her data is stored in the identity hub <NUM>. As another example, a user has multiple DIDs and has shared data amongst the multiple DIDs, alternatively, the user has used different DID management modules to access the same data. Based on the data sharing activities, the service provider of the identity hub <NUM> correlate the relationships of different DIDs and find out that two DIDs is related or owned by the same owner. Thus, the user's privacy is compromised.

The principles described herein will solve these potential privacy concerns of DID owners by encrypting the personal data stored in the identity hub <NUM>. The encryption/decryption keys are not stored or accessible by the identity hub <NUM>, so that the DID owners not only have great control over their data from other DID owners or users, but also have their privacy protected from the service providers.

There are many different objects stored in the identity hub <NUM>. A data object is a file, a folder, or any portion of data stored in the identity hub <NUM>. The whole identity hub <NUM> is encrypted with one encryption/decryption key as one object. Alternatively, a different portion of the data stored in the identity hub <NUM> is encrypted with different encryption/decryption keys.

In another example embodiment, verifiable claims are issued and stored at the identity hub <NUM>. For example, a verifiable claim that is associated with a DID owner <NUM> is issued by a claim issuing entity, and the issued verifiable claim is stored at the identity hub <NUM> that is associated with the DID owner <NUM>. The DID owner <NUM> send the verifiable claim to another entity when the other entity requires to verify the credential of the DID owner. For example, the DID owner <NUM> is a person holding a driver's license, and the claim issuing entity is a DMV that has issued the DID owner's driver's license. The DMV issue a verifiable claim that verifies that the DID owner <NUM> is holding a valid driver's license. The DID owner <NUM> stores the verifiable claim in the identity hub <NUM>. Another entity is a rental car company, which requires the DID owner <NUM> to show that he/she has a valid driver's license. The DID owner then sends the verifiable claim stored at the identity hub <NUM> to the rental car company.

As briefly discussed above, when a DID owner uses one DID to communicate with many different entities, the DID owner's personally identifiable information may be reconstructed based on the correlation of the communications amongst these many different entities. To further protect a DID owner's privacy, pairwise DIDs can be employed. A pair of pairwise DIDs are a pair of DIDs that are used by two DID owners only to communicate with each other. Each DID owner can generate many pairwise DIDs, each of which is only used to communicate with another entity. As such, even though the same DID owner is communicating with many different entities, each of these entities does not know the communications involving the same DID owner using other pairwise DIDs. Thus, the DID owner's privacy is further protected.

<FIG> illustrates an example environment <NUM>, in which Alice <NUM>, Bob <NUM>, and a service provider <NUM> are using pairwise DIDs to communicate with each other. Each of Alice <NUM>, Bob <NUM>, and the service provider <NUM> corresponds to a DID owner <NUM> of <FIG>. For example, Alice <NUM> owns multiple pairwise DIDs, including DID A <NUM>, DID B <NUM>, and DID C <NUM>. The ellipsis <NUM> represents that Alice may own any number of pairwise DIDs or any number of non-pairwise DIDs. Similarly, Bob <NUM> also owns multiple pairwise DIDs, including DID E <NUM>, DID F <NUM>, and DID G <NUM>. The ellipsis <NUM> represents that Bob may own any number of pairwise DIDs or any number of non-pairwise DIDs. The service provider <NUM> also owns multiple pairwise DIDs, including DID H <NUM>, DID F <NUM>, and DID J <NUM>. The ellipsis <NUM> represents that the service provider <NUM> may own any number of pairwise DIDs or any number of non-pairwise DIDs. As illustrated in <FIG>, DID A <NUM> owned by Alice <NUM> and DID E <NUM> owned by Bob <NUM> are a pair of pairwise DIDs. As such, Alice <NUM> and Bob <NUM> use only DID A <NUM> and DID E <NUM> to communicate with each other, which is represented by arrow <NUM>. Similarly, DID B <NUM> owned by Alice <NUM> and DID H <NUM> owned by the service provider <NUM> are a pair of pairwise DIDs. As such, Alice <NUM> and service provider <NUM> use only DID B <NUM> and DID H <NUM> to communicate with each other, which is represented by arrow <NUM>. Again, similarly, DID F <NUM> owned by Bob <NUM> and DID I <NUM> owned by service provider <NUM> are a pair of pairwise DIDs, which are only used for communicating between Bob <NUM> and service provider <NUM> (represented by arrow <NUM>).

Since each pair of the pairwise DIDs is only used to communicate between two DID owners, in many cases, a relationship between the two DID owners can be clearly defined. In some embodiments, the relationship between a pair of pairwise DIDs are recorded in the management module of the DID owners. In some embodiments, such relationship data is stored with each pairwise DID (e.g., DID documents) or recorded in a distributed ledger. Alternatively, or in addition, the relationship of each pair of pairwise DIDs are recorded in one data structure (e.g., a table).

<FIG> illustrates an example data structure 600A that records relationships of pairwise DIDs owned by Alice <NUM>. For example, Alice's DID A <NUM> is used to communicate with Bob's DID <NUM>, and the relationship between Alice and Bob is child-parent, i.e., Alice is Bob's child. As another example, Alice's DID B <NUM> is used to communicate with service provider <NUM>, and the relationship between Alice <NUM> and service provider <NUM> is the employee-employer relationship, i.e., Alice <NUM> is an employee of the service provider <NUM>. The ellipsis 611A, 612A, 533A represent that there may be any number of pairs of pairwise DIDs, whose relationships are recorded in the table 600A.

In some embodiments, based on the relationships between each pair of pairwise DIDs, Alice's DID management module, user agent, and/or ID hub is configured to determine a scope of permission that is to be delegated from Alice's pairwise DID to the corresponding pairwise DID. In some embodiments, multiple relationships and multiple scopes of permission are mapped to each other. The mapping data is recorded in a storage at Alice's DID management module, user agent, and/or ID hub. <FIG> illustrates an example data structure storing mapping data 600B. As illustrated in <FIG>, the child-parent relationship 621B is mapped to delegation scope X 631B; the employee-employer relationship 622B is mapped to delegation scope Y 532B; and the customer-service relationship 623B is mapped to delegation scope Z 633B. The ellipsis 624B and 634B represent that there may be any number of mapped pairs of relationship and delegation scope.

In some cases, the computing system (e.g., Alice's management module or wallet app, user agent, or ID hub) is configured to compile the data structure 600A and/or 600B automatically based on the data recorded in DID documents or some other Alice's personal data. Alternatively, or in addition, at least a portion of the data structure 600A and/or 600B is generated based on user (e.g., Alice's) input(s). <FIG> merely illustrate a simple example of how the relationship data and delegation data may be stored. Various other data structures may be implemented to achieve similar purposes. For example, in some cases, the data structures 600A and 600B may be relationally stored. Alternatively, or in addition, the data structures 600A and 600B may be stored in a same data structure.

As briefly mentioned above, in some cases, the DID owners are allowed to define the relationships between their pairwise DIDs and the scope of permission that is to be granted. <FIG> illustrates an example user interface 600C of a management module. The user interface 600C includes a selection list 610C that allows a user (e.g., DID owner) to select one or more particular pairs of the pairwise DIDs. The user interface 600C also includes a selection list 620C that allows the user to select one or more relationships that apply to the selected pairs of pairwise DIDs. The user interface 600C also includes a menu 630C that allows the user to select or manually define a scope of permission that is to be granted to the corresponding DID. Once the user presses the confirm button 640C, the user inputs are recorded in a data structure (e.g., the data structures 600A and/or 600B) that the computing system has access to.

Based on the data structures 600A and 600B, the computing system is configured to automatically determine a relationship between two DID owners and/or automatically delegate a scope of permission to a pairwise DID. For example, the computing system accesses the relationship data 600A to determine the relationship between a particular pairwise DID (e.g., DID A <NUM>) and its corresponding pairwise DID (e.g., DID E <NUM> owned by Bob <NUM>). Based on the determined relationship (e.g., child-parent relationship), the computing system then accesses the delegation data 600B to determine a scope of permission (e.g., scope X <NUM>) that is to be delegated to the corresponding pairwise DID (e.g., DID E <NUM> owned by Bob <NUM>). In response to a determination, the computing system delegates the scope of permission (e.g., scope X <NUM>) to the corresponding pairwise DID (e.g., DID E <NUM> owned by Bob <NUM>).

There are many various mechanisms that may be implemented to delegate a scope of permission from one DID to another DID. <FIG> and <FIG> illustrate some embodiments that can be implemented in delegator's DID owners' management module, user agent, and/or the ID hub. In some embodiments, when Alice's DID <NUM> is to delegate a scope of permission to Bob's DID <NUM>, the Alice's computing system (e.g., Alice's management module, user agent, or ID hub) updates the DID document of Alice's DID <NUM> or the DID document of Bob's DID <NUM> to record the delegation of the scope of permission. In some embodiments, a new DID is generated, and delegation of the scope of permission is recorded in the DID document of the new DID. A portion of the data related to the delegation is then propagated onto the distributed ledger.

<FIG> illustrates an example delegation proof <NUM> for delegating a scope of permission from Alice <NUM> to Bob <NUM>. The delegation proof <NUM> includes data <NUM> that is related to the type of the record. Here, the type of record is "delegation" <NUM>. The record <NUM> also includes data related to the delegator <NUM>. Here, the delegator is "Alice's DID" <NUM>. The record <NUM> also includes data related to "granted key". Here, the granted key is a key associated with Bob's DID.

The record <NUM> also needs to define the scope of permission that is granted. In some embodiments, the definition of the scope of permission includes one or more restrictions. As illustrated in <FIG>, the record <NUM> includes data <NUM> that is related to one or more restrictions. The one or more restrictions include, but are not limited to, (<NUM>) an expiration time of the delegation, (<NUM>) a predetermined number of times that the delegatee is allowed to access a portion of data or service, or (<NUM>) a restriction that restricts the access to a portion of data, such as (i) a read permission, (ii) a write permission, (iii) a delete permission, or (iv) a delegation permission. In some embodiments, the one or more restrictions include one or more conditions, which are required to be satisfied each time the delegatee requests for accessing to the delegated permission. The one or more conditions include, but are not limited to, (i) requiring the delegatee DID to pay a predetermined amount of cryptocurrency, (ii) requiring the delegatee DID to provide one or more verifiable claims, or (iii) requiring the delegatee DID to provide particular personal data, such as (a) an email address, (b) a phone number, (c) a location, (d) a name of the delegatee, (e) an IP address, or (f) a device identifier. As illustrated in <FIG>, the one or more restrictions <NUM> indicate that Bob's DID is restricted to only read a portion of Alice's personal data (i.e., Bob's DID cannot modify Alice's personal data).

Finally, the delegation data <NUM>-<NUM> is signed by a private key <NUM> associated with Alice's DID. The signature <NUM> includes the type of the signature <NUM>, the time the signature is created <NUM>, the creator <NUM>, and the signature value <NUM>. Here, the type of signature is Rsa Signature, the creator is Alice's DID <NUM>, and the signature <NUM> is generated by a private key associated with Alice's DID <NUM>. In some embodiments, the delegation proof is stored with the DID document of Alice DID and/or the DID document of Bob's DID. In some embodiments, a new DID is generated, and the delegation data is associated and stored with the DID document of the new DID. At least a portion of data related to the delegation proof is propagated onto the distributed ledger. In some embodiments, the complete delegation proof is propagated onto the distributed ledger. Alternatively, a transformed record (e.g., a hash, a URL, or an identifier of the delegation proof) is propagated onto the distributed ledger.

<FIG> further illustrates an example communication pattern <NUM> that occurs when a delegatee (e.g., Bob <NUM>) requests for access to a delegated scope of permission (e.g., Alice's data). As illustrated in <FIG>, Bob's device (e.g., Bob's management module, user agent, and/or ID hub) first requests for accessing to Alice's data, which is represented by arrow <NUM>. The request is sent to Alice's device <NUM> (e.g., Alice's management module, user agent, and/or ID hub). Receiving the request, Alice's device <NUM> then requests Bob's device <NUM> for proving that Bob <NUM> is delegated the scope of permission for accessing the requested Alice's data, which is represented by arrow <NUM>. Bob's device <NUM>, in turn, generates proof data, which is represented by arrow <NUM>. The proof data includes at least the signature signed by Alice's private key (e.g., signature <NUM> of <FIG>). The proof data is then packaged in a response and sent to Alice's device <NUM>, which is represented by arrow <NUM>.

Receiving the proof data, Alice's device <NUM> then validates the response using its key and/or a portion of data related to the delegation proof propagated onto the distributed ledger <NUM>, which is represented by arrow <NUM>. For example, when the signature signed by Alice's private key is received, Alice's device <NUM> tries to decrypt the signature by a corresponding public key. The decryption result (and/or transformed decryption result) is then used to compare to the data propagated on the distributed ledger <NUM> to determine whether the proof data is valid. When the scope of permission includes one or more restrictions or conditions, Alice's device <NUM> will also verify whether the requested scope of permission falls within the one or more restrictions and/or whether the one or more conditions are satisfied. For example, if a condition requires Bob to pay a predetermined amount of cryptocurrency, the proof data is required to show a proof of payment. As another example, if a condition requires Bob to provide his email address, the proof data is required to include Bob's email address. If the proof data is valid, Alice's device <NUM> approves the Bob's request, otherwise, Alice's device <NUM> denies the Bob's request, which is represented by arrow <NUM>.

<FIG> illustrates a flowchart of an example method <NUM> for delegating a scope of permission between two pairwise DIDs. The DID that delegates the scope of permission is called a delegator DID or simply delegator, and the DID that receives the delegation is called a delegatee DID or simply delegatee. The method <NUM> is performed by a computing system associated with a delegator DID (e.g., a management module, a user agent, and/or an ID hub). The method <NUM> includes determining a relationship of owners of a pairwise DID (<NUM>). Based on the determined relationship, a scope of permission is delegated from the delegator to the delegatee (<NUM>).

In some embodiments, the delegation includes defining the scope of permission (<NUM>). For example, in some cases, the definition of the scope of permission includes one or more restrictions related to the scope of permission (<NUM>). The one or more restrictions include, but are not limited to, (<NUM>) an expiration time of the delegation, (<NUM>) a predetermined number of times that the delegatee is allowed to access a portion of data or service, or (<NUM>) a restriction that restricts the access to a portion of data, such as (i) a read permission, (ii) a write permission, (iii) a delete permission, or (iv) a delegation permission. In some embodiments, the one or more restrictions include one or more conditions, which are required to be satisfied each time the delegatee requests for accessing to the delegated permission. The one or more conditions include, but are not limited to, (i) requiring the delegatee DID to pay a predetermined amount of cryptocurrency, (ii) requiring the delegatee DID to provide one or more verifiable claims, or (iii) requiring the delegatee DID to provide particular personal data, such as (a) an email address, (b) a phone number (c) a location, (d) a name of the delegatee, (e) an IP address, or (f) a device identifier.

In some embodiments, the delegation includes granting a delegatee's key the scope of permission (<NUM>). The delegation also includes generating a signature by a delegator's private key (<NUM>) and recording data related to the delegation in a DID document (e.g., the delegator's DID document, the delegatee's DID document, and/or a DID document of a new DID) (<NUM>). Finally, at least a portion of data related to the delegation is propagated onto the distributed ledger (<NUM>). In some embodiments, the complete delegation proof is propagated onto the distributed ledger. In some embodiments, a transformed delegation proof, such as a hash, a URL of the DID document, or an identifier of the delegation proof, is propagated onto the distributed ledger.

<FIG> further illustrates a flowchart of an example method <NUM> for determining a relationship between DID owners of a pair of pairwise DIDs, which corresponds to the step <NUM> of <FIG>. The method <NUM> includes accessing mapping data that maps a plurality of relationships to a plurality of scope of permissions for delegation (<NUM>). An example of mapping data is illustrated in <FIG> above.

In some embodiments, the mapping data is entered by users manually (<NUM>, <NUM>). In some embodiments, the mapping data is generated based on the delegator's personal data, data recorded in the DID documents and/or data propagated onto the distributed ledger. In some embodiments, the automatically generated mapping data is also allowed to be manually updated by users (e.g., DID owners). For example, in some cases, a user is not only allowed to update the mapping data (<NUM>), the user is also allowed to update the relationship between the owners of the pairwise DIDs (<NUM>). Based on the mapping data (<NUM>) and/or the user's inputs(<NUM>, <NUM>), the computing system then determines a particular scope of permission corresponding to a particular relationship (<NUM>).

After the delegatee receives the delegation of the scope of permission, the delegatee will be allowed to access the delegated scope of permission. <FIG> illustrates a flowchart of an example method <NUM> for allowing a delegatee to access a delegated scope of permission in response to proving that the delegation is valid. The method <NUM> is also likely implemented in a computing system that is associated with the delegator's DID. The method <NUM> includes receiving a request from a delegatee DID for accessing a scope of permission (<NUM>). In response to the request, the computing system requests the delegatee for proof of the delegation (<NUM>). Once the proof code from the delegatee is received (<NUM>), the computing system validates the proof code (<NUM>).

In some embodiments, when the proof code includes a signature signed by a delegator's private key, the validation of the proof code includes decrypting the signature by a public key of delegator (<NUM>). In some embodiments, the validation of the proof code also includes retrieving data related to the delegation in a distributed ledger (<NUM>). The computing system then analyzes the decrypted signature and the retrieved delegation data from the distributed ledger to determine whether the proof data is valid (<NUM>). The validation of the proof code also includes verifying the requested scope of permission is within the delegated scope (<NUM>).

For example, when the delegated scope of permission includes one or more restrictions, the computing system verifies that the requested scope of permission does not fall within the restrictions. In some embodiments, when the restrictions include one or more conditions for accessing the scope of permission, the validation of the proof code also includes verifying that the one or more conditions are satisfied (<NUM>). For example, when a condition requires the delegatee to pay a predetermined amount of cryptocurrency, the delegatee will need to further show a proof of the payment in the proof code. As another example, when a condition requires the delegatee to provide an email address, the proof code needs to include the email address. Finally, in response to a determination that the proof data is valid, the computing system grants the delegatee's request; otherwise, the computing system denies the delegatee's request (<NUM>).

Claim 1:
A computing system (<NUM>) comprising:
one or more processors (<NUM>); and
one or more computer-readable media (<NUM>) having thereon computer-executable instructions (<NUM>) that are structured such that, when executed by the one or more processors (<NUM>), cause the computing system (<NUM>) to perform the following:
determine (<NUM>) a relationship (630A) between a first decentralized identifier, DID, owner (<NUM>) of a first DID (<NUM>) and a second DID owner (<NUM>) of a second DID (<NUM>), the first DID (<NUM>) and the second DID (<NUM>) being pairwise DIDs (<NUM>, <NUM>); and
based on the relationship (630A), delegate (<NUM>) a scope of permission (630C) owned by the first DID (<NUM>) to the second DID (<NUM>), comprising:
define (<NUM>) the scope of permission (<NUM>);
grant (<NUM>) a public key of (<NUM>) the second DID (<NUM>) the defined scope of permission (<NUM>);
generate (<NUM>) a signature (<NUM>) by a private key (<NUM>) of the first DID (<NUM>), proving the delegation of the defined scope of permission (<NUM>) to the public key (<NUM>) of the second DID (<NUM>); and
propagate (<NUM>) a portion of data related to the delegation (<NUM>) onto a distributed ledger (<NUM>, <NUM>).