This Technical Report continues the convention adopted in . Terms beginning with a capital letter have the meaning defined in Table 1 that updates and extends the terms defined in . Terms beginning with a small letter have the meaning commonly defined for the context in which they are used. For instance, Table 1 defines User and Object but does not define human and object.
A dash “-” preceding a Term in Table 1 means the following:
- If the font is normal, the Term in the table without a dash and preceding the one with a dash should be placed before that Term. The notation is used to concentrate in one place all the Terms that are composed of, e.g., the word Decentralised followed by one of the words Application, Autonomous Organisation, Finance, System, and User Identifier, or definitions belonging to the same class, e.g., Action and Items.
- If the font is italic, the Term in the table without a dash and preceding the one with a dash should be placed after that Term. The notation is used to concentrate in one place all the Terms that are composed of, e.g., the word Interface preceded by one of the words Brain-Computer, Haptic, Speech, and Visual.
|Account||An Item that uniquely references a human who has Registered.|
|Action||An operation affecting an Item.|
|– Authenticate||The Action of requesting confirmation that an Entity MM-Embedded at an M-Location is what it claims to be.|
|– Author||The Action of calling a Service to obtain an Entity with associated OutRights to Act on the Entity.|
|– Change||The Action of requesting that a Service modify the Rights of a User whose Persona is Embedded at an M-Location and provide OutRights, e.g., to further Change the Rights.|
|– Discover||The Action of requesting that a Service provide a DiscoveryOut Item containing the IDs of the Items relevant to the DiscoverIn Item with the OutRights to Act on the DiscoveryOut Item.|
|– Hide||The Action of requesting that a Service make the ID of an Item unavailable and provide OutRights, e.g., to make the ID available again.|
|– Identify||The Action of requesting that a Service produce an Item from MM-Sent or UM-Sent Data and Metadata or update an Item with the OutRights to Act on the Item.|
|– UM-Import||The Action of a User requesting that a Service read Data & Metadata stored at an Address.|
|– Inform||The Action of requesting that a Service provide an InformOut Item containing information about an InItem, such as the Metadata of the InItem, with the OutRights to Act on the InformOut Item.|
|– Interpret||The Action of requesting that a Service provide an InterpretOut Item containing interpretation of an InItem, such as translation or extraction of Personal Status, with the OutRights to Act on the InterpretOut Item.|
|– MM-Add||The Action of requesting that a Service add an Entity at an M-Location with a Spatial Attitude and provide OutRights to Act on the MM-Added Entity.|
|– MM-Animate||The Action of requesting that a Service change the features of an Entity MM-Embedded at an M-Location with a Stream and provide the OutRights to Act on the MM-Added Entity.|
|– MM-Capture||The Action of requesting that a Service MM-Send selected Entities MM-Embedded at an M-Location to a User.|
|– MM-Disable||The Action of requesting that a Service stop MM-Enabling selected Entities Embedded at an M-Location and provide OutRights to Act on the MM-Disabled Entities.|
|– MM-Embed||The Composite Action of requesting that a Service MM-Add and MM-Enable an Entity either located at a Service or at an M-Location at a destination M-Location with a Spatial Attitude and provide OutRights to Act on the MM-Embedded Entity.|
|– MM-Enable||The Action of enabling a User to MM-Capture an Entity MM-Added at an M-Location.|
|– MM-Send||The Action of requesting that a Process forward to another Process:
1. An Item with OutRights to Act on the Item, or
|– MU-Actuate||The Action of requesting that a Device present at a U-Location as Media with a Spatial Attitude an Entity MM-Embedded at an M-Location.|
|– MU-Export||The Action of requesting that a Process store an Item at an Address.|
|– MU-Render||The Composite Action of requesting that:
1. A Service MM-Send selected Entities Embedded at an M-Location to a Device.
2. The Device MU-Actuate at a U-Location with a Spatial Attitude the Entity received.
|– Post||The Action of requesting that a Marketplace include an Asset.|
|– Register||The Action of a human requesting that an M-Instance/Environment grant their Users the Rights to perform Actions in the M-Instance/Environment.|
|– Track||The Composite Action of requesting:
1. A Service to MM-Add a Persona at an M-Location with a Spatial Attitude.
2. A Service to UM-Animate the Persona MM-Added at an M-Location.
3. A Service to MU-Render specified Entities at the M-Location to a U-Location.
|– Transact||The Action of a User1 requesting that a Service:
1. Assign Rights on an Asset to User2.
2.1. Wallet1 of User1 to be increased by Value1.
2.2. Wallet2 of User2 to be decreased by Value2.
2.3. Wallet3 of the Service enabling/facilitating the Transaction to be increased by Value3 (optionally).
|– UM-Animate||The Composite Action of requesting:
1. To UM-Capture an animation stream extracted from a scene at a U-Location.
2. To UM-Send the animation stream and Metadata to a User.
3. To Identify the Animation Stream.
4. To MM-Animate the Model MM-Embedded at the M-Location using the Animation Stream.
|– UM-Capture||The Action of requesting that a Device acquire Media from a scene at a U-Location.|
|– UM Import||The Action of a User requesting that a Service make available Data & Metadata, or an Item stored at an Address.|
|– UM-Render||The Composite Action of requesting:
1. A Device to UM-Capture a scene at U-Location.
2. The Device to MM-Send Data and Device-provided Metadata to a User.
3. A Service to Identify an Entity from UM-Sent Data and Metadata.
4. A Service to MM-Embed the Entity at an M-Location with a Spatial Attitude.
|Avatar||A rendered Digital Human.|
|Blockchain||A shared immutable ledger stored on a peer-to-peer network of computers.|
|Common Metaverse Specifications||(CMS) The collection of standards specifying the technologies and recognised Technology Profiles enabling Metaverse Interoperability including.|
|Connected Autonomous Vehicle||(CAV) A vehicle able to autonomously reach a U-Location by using its own sensing and processing capabilities to generate an M-Instance, sharing the M-Instance with other CAVs and issuing actuation commands.|
|Data||Information represented in digital form.|
|– Format||The syntax and semantics of Data.|
|– Type||Data characterised by its specific Format.|
|Data Type||Data used in Actions and Items.|
|– Address||A URL.|
|– Amount||A number expressing a Value in a Currency.|
|– Cognitive State||The representation of a User’s Personal Status that reflects the way they understand the Environment, such as “Confused”, “Dubious”, “Convinced”.|
|– Coordinates||A set of numbers representing a Position in a Metaverse Environment using a coordinate system.|
|– Currency||A medium of exchange enabling Transactions in a Metaverse Instance.|
|– Emotion||The representation of a User’s Personal Status that results from their interaction with an Environment, such as “Angry”, “Sad”, “Determined”.|
|– Orientation||The set of the 3 roll, pitch, yaw angles indicating the rotation around the principal axis (x) of an Object, its y axis having an angle of 90˚ counterclockwise (right-to-left) with the x axis and its z axis (pointing up toward the viewer viewing from above).|
|– Personal Status||The representation of the information internal to a User characterising their behaviour.|
|– Point||A point in an M-Environment identified by the set of local Coordinates.|
|– Point of View||The Spatial Attitude of a Digital Human watching the Environment.|
|– Position||The coordinates of an Object with respect to a set of coordinates in a Metaverse Environment.|
|– Social Attitude||The representation of a User’s Personal Status related to the way the User intends to position vis-à-vis a Metaverse Environment, e.g., “Respectful”, “Confrontational”, “Soothing”.|
|– Spatial Attitude||The Position and Orientation of an Entity, and their velocities and accelerations.|
|– Time||A measure of time.|
|– Application||(dApp) A Process that runs on a decentralised computing system.|
|– Autonomous Organisation||(DAO) An organisation without centralised leadership, where the main governing rules are typically encoded by means of a Smart Contract.|
|– Finance||(DeFi) A financial technology based on a secure infrastructure of distributed ledgers like those used by crypto currencies.|
|– System||A set of dApps enabling a group of Users to make decisions without a centralised entity.|
– A U-Environment to interact with an M-Instance and/or
– An M-Instance to interact with a U-Environment.
|Duty||A moral or legal obligation to act or behave.|
|Entitlement||The state of a User having certain Rights in an M-Instance.|
|Functionality||An attribute of an M-Instance expected to be enabled by a Common Metaverse Specifications Tool.|
|– Digital||Either a Digitised or a Virtual Human.|
|– Digitised||The digital representation of a human.|
|– Virtual||A computer-created Object that has a human appearance when rendered but is not a Digitised Human.|
|Governance||The action or manner of directing and controlling actors of the Metaverse Ecosystem.|
|Information and Communication Technologies||(ICT) Technologies that enable the processing and distribution of information via the network.|
|Interface||A communication pathway enabling systems to interact.|
|– Brain-Computer||(BCI) A communication pathway that allows a human to interact with an M-Instance by sensing and processing the electrical activity of the brain.|
|– Haptic||A communication pathway that allows a human to interact with an M-Instance through bodily movements and sensations.|
|– Speech||A communication pathway that allows a human to interact with an M-Instance using spoken language.|
|– Visual||A communication pathway that allows a human to interact with an M-Instance through bodily movements and visual messages.|
|Item||Data and Metadata recognised and identified by an M-Instance.|
|– Account||An Item that uniquely references a human who has Registered. A User may have more than one Account with one or more Services.|
|– Activity Data||An Item containing the record of the Actions of a User.|
|– Asset||An Item Embedded at an M-Location or Posted to a Service that may be the object of a Transaction.|
|– DiscoverIn||An Item containing a description of the Items to be Discovered.|
|– DiscoverOut||An Item containing the description of the Items Discovered.|
|– Entity||Any of the following Items that can be MU-Rendered: Object, Model, Scene, Event, and Experience.|
|– Event||An Entity corresponding to an M-Location, its Entities and their Animations starting from Start Time until End Time.|
|– Experience||An Entity comprising an Event as MM-Captured by a User and the User Interactions with the Entities of the Event.|
|– Identifier||An Item that uniquely references an Item. The Item can have more than one Identifier.|
|– InformIn||An Item containing a description of the Item on which information is requested.|
|– InformOut||An Item containing the description of the Item object of an InformIn.|
|– Interaction||An Item containing the list of Actions made by a User on the Entities at an M-Locations and the corresponding Times.|
|– InterpretIn||An Item containing a description of the Item to be Interpreted.|
|– InterpretOut||An Item containing the description of the Item object of an InterpretIn.|
|– Ledger||An Item containing a list of Transactions involving Assets.|
|– Map||An Item containing a structure establishing a correspondence between U-Locations with M-Locations.|
|– M-Environment||An identifiable portion of an M-Instance covered by an Account.|
|– Message||An Item containing application-specific Data MM-Sent by a Source to a Destination.|
|– M-Instance||A Metaverse implementation.|
|– M-Location||An identifiable delimited portion of an M-Environment.|
|– Model||An Object representing an object with its features ready to be UM-Animated by a Stream or MM-Animated.|
|– Object||An Entity representing an object. Currently, the following types of Objects are supported: Audio, Visual, and Haptic.|
|– Persona||A Model of a human ready.|
|– Personal Profile||An Item containing the Data about the human represented by User.|
|– Provenance||The Ledger associated with a specific Asset.|
|– Request-Action||An Item containing the request to a Service to perform an Action. This definition applies to all Actions of this Technical Report.|
|– Response-Action||An Item containing the response of a Service to a Request-Action. This definition applies to all Actions of this Technical Report.|
|– Rights||An Item expressing the ability of a User to perform an Action on an Item until a Time.|
|– Rules||An Item expressing the terms and conditions under which a User operates in an M-Instance/Environment.|
|– Scene||A possibly hierarchical Composition of Objects each having a Spatial Attitude.|
|– Social Graph||A representation of a User’s network of connections with Items, Processes, and Services.|
|– Stream||An Item made by a continuous flow of Data.|
|– Transaction||Item representing the changed state of the Accounts and the Rights of a seller User and a buyer User on an Asset and optionally of the Service facilitating/enabling the Transaction:
1. The Value moving into the Wallet of User 1 (seller).
2. The Value moved from the Wallet of User2 (buyer).
3. The Value moved into the Wallet of User 3 (service) – optional.
4. The Time the Values were moved.
5. The Rights to Act owned by User1 before Time.
The Rights to Act owned by User2 after Time.
|– U-Environment||A portion of the Universe.|
|– U-Location||An identifiable delimited portion of a U-Environment.|
|– User Data||An Item containing Activity Data, Personae, Social Graph, and User Profile of a User.|
|– Value||An Amount and the Currency with which the Amount is expressed.|
|– Wallet||A container of Currency units. In general, a Wallet is implemented outside of the Environment.|
|Level||A subdivision of a Profile indicating the completeness of the user experience provided by the Profile.|
|Metadata||An attribute of Data, e.g., of a User, an Environment, an Object, or a Service.|
|Metaverse||A set of services and devices implementing a subset of the following functions: 1) sense data from real environments, 2) process sensed data 3) create one or more digital environments populated by digitised and/or virtual objects, and 4) process the objects to 5) produce effects on real and/or virtual environments that 6) are consistent with the goal set to the metaverse, and achieved 7) with the capabilities of 8) and within the rules set to the metaverse.|
|– Action||An operation affecting an Item.|
|– Actuator||A component of a Device able to MU-Render an Entity and environment Data to a U-Environment.|
|– Asset||An Item Embedded at an M-Location or Posted to a Service that may be the object of a Transaction.|
|– Ecosystem||The ensemble of entities and rules ensuring that Metaverse Instances operate in the interest of Metaverse Stakeholders.|
|– Enabling Service Layer||The set of Services such as payment, security, identity, privacy, etc. that enable operation of an M-Instance.|
|– Entity||Any of the following Items that can be MU-Rendered: Scene, Object, Model, Event, and Experience.|
|– Environment||(M-Environment) A portion of an M-Instance run by a Registration system.|
|– Experience Layer||The set of functions, such as Devices, that generate Experiences.|
|– Functionality||The ability of an M-Instance to perform Actions that further the goals set by the Metaverse Manager for the M-Instance.|
|– Industry||The collection of players that support the design, development, deployment, operation, and content and service provisioning to Metaverse Instances.|
|– Instance||(M-Instance) An implementation providing all or a subset of the Metaverse Functionalities.|
|– Interoperability||The ability of M-Instance #1 to use data from and as intended by M-Instance #2. Interoperability can be Direct or Mediated by a conversion service.|
|– Infrastructure Layer||The set of functions such as network, transport, storage, and (cloud, edge) processing that enable an M-Instance to operate.|
|– Item||Metaverse-specific Data that may include Metadata that may include Rights.|
|– Level||A subdivision of a Profile that indicates the degree of completeness of the user experience provided by that Level.|
|– Location||(M-Location) An identifiable delimited portion of the Metaverse.|
|– Manager||The entity overseeing the operation of an M-Instance.|
|– Operator||The entity overseeing the operation of an M-Environment.|
|– Partner||A User participating in activities of a Metaverse Operator (i.e., a business customer of an Operator)|
|– Platform Layer||The set of Services, such as content creation, content discovery, and content access functions that enable an M-Instance to operate.|
|– Process||The instance of a program being executed.|
|– Profile||A recognised subset of the Functionalities (Functionality Profile) or Technologies (Technology Profile) specified by the Common Metaverse Specifications.|
|– Sensor||A Device able to UM-Capture a scene and other environment information as Data.|
|– Specifications||(CMS) A collection of standards specifying the technologies enabling Metaverse Interoperability.|
|– Stakeholder||An entity performing a function aimed at achieving a goal in an M-Instance.|
|– State||The set of values and stored data of an M-Instance at a given time.|
|– Tool||A Technology or group of Technologies enabling an M-Instance to provide a Functionality.|
|– Technology||A structured application of scientific and/or technical methods that supports a Functionality.|
|– User||One or a set of Processes representing a human.|
|– Audio||The digital representation of an object or a computer-generated Object that can be rendered to and perceived by a human ear.|
|– Autonomous||A Virtual Object animated by a Process giving it the ability to act (e.g., move, speak, respond, execute) with a degree of autonomy.|
|– Composite||An Object that includes more than one Object Type.|
|– Digital||A Digitised or a Virtual Object.|
|– Digitised||The digital representation of an object.|
|– Haptic||An Object with the haptic features of an object able to be rendered to provide haptic sensations in a human.|
|– Human||An Object representing a human.|
|– Speech||The digital representation of a sound emitted by the vocal tract of a human or generated by a computer with similar audio characteristics.|
|– Type||One of Audio, Visual, Haptic, Olfaction, and Gustation.|
|– Virtual||A computer-generated Object that is not a Digitised Object.|
|– Visual||The digital representation of an object captured by an electromagnetic or high-frequency audio signal or computer-generated that can be rendered to and perceived by a human eye.|
|Oracle||A Service providing information from a U-Environment to a Blockchain.|
|Privacy||The Rights of a User to keep their Personal Data secret.|
|– App||An application-specific Program executed on a Device.|
|– Device||A Process able to:
1. UM-Capture Data from a U-Location
2. UM-Send Data and Metadata to a User.
1. MM-Send an Entity from an M-Location to the Device.
2. MU-Render an Entity at a U-Location.
|– Service||A Process that can be called to provide Functionalities.|
|– User||A Process representing a UM-Captured human as a Persona that are either UM-Animated by a Stream or MM-Animated by an autonomous agent.|
|Profile||Set of base standards and/or their subsets.|
|– Functionality||The grouping of Functionalities offered by a Metaverse Profile.|
|– Technology||The grouping of Technologies offered by a Metaverse Profile.|
|Registration||The provisioning by a human of a subset of User Data to an M-Instance/Environment to obtain an Account.|
|Representation||Data that represent an entity of a U-Environment in an M-Instance.|
|– Agency||The subjective awareness of being able to decide, execute, and control one’s own actions in an M-Environment.|
|– Embodiment||The engagement of senses to form a complete Environment Experience.|
|– Presence||The feeling of being in an M-Environment with other Digital Humans for real.|
|Smart Contract||A Program stored on a Blockchain that runs when activated by an external entity, e.g., a User or another Smart Contract.|
|– Fungible||A representation of an Asset that is interchangeable with other Assets of the same type.|
|– Non-Fungible||(NFT) A unique digital identifier of an Asset that:
– Cannot be copied (i.e., a copy is known to be a copy), substituted, or subdivided.
– Is recorded in a digital ledger.
– Is used to certify Object authenticity and ownership.
|Trust-less system||A system allowing a User to make reliable Transactions without trusting or knowing the parties the User makes Transactions with.|
|Universe||The physical world.|
|– Environment||(U-Environment) A delimited portion of the Universe.|
|– Location||(U-Location) An identifiable delimited portion of the Universe.|
|Use Case||An example of how an application domain can be supported by an M-Instance/Environment.|
|User Keys||The pair of public and private keys where the public key is used to encrypt, and the private key is used to both encrypt and decrypt Data.|
|– Decentralised||An Identifier that enables the verifiable association with a User without requiring a centralised registry.|
|– Self-Sovereign||A Decentralised Identifier derived from the User’s Public Key owned and managed directly by the User based on the knowledge of their own Private Key, e.g., stored in the Crypto Wallet enabled by the Blockchain underpinning the Metaverse Instance.|
|– Crypto||Software or hardware holding the Public and Private Keys of a User to enable them to make Transactions by accessing their Account on a Blockchain.|