Patent Description:
Identity and access management (IAM) is a framework of processes, policies, and technologies that facilitates the management of digital identities. An IAM framework can control user access to protected resources (e.g., data, documents, files, software, hardware, services, and the like) corresponding to an entity, such as, for example, an enterprise, business, company, organization, institution, agency, or the like. IAM systems can be deployed on premises, provided by a third-party vendor through a cloud-based subscription model, or deployed in a hybrid model. Typical systems used for IAM include single sign-on systems, two-factor authentication, multifactor authentication, privileged access management, and token-based authorization.

Token-based authentication (e.g., OAuth <NUM>) is a protocol which allows end users and services to verify their identity and in return receive a unique access token. During the lifetime of an access token (i.e., a defined period of time), end users and services can access a protected resource, such as a cloud service, which the access token has been issued for. First, an end user or service requests access to the protected resource. That may involve a login with credentials, such as username and password. The authorization server determines whether the end user or service should have access by, for example, comparing the received credentials with stored credentials corresponding to the end user or service. After credential authentication or verification, the authorization server issues the access token and refresh token to the end user or service. The authorization server signs the access token using either a private secret or a public/private key.

Before a particular client web application of the end user or service can access a particular protected resource using an application programming interface, the client web application must obtain the access token that grants access to that particular application programming interface. The access token contains an end user or service identifier for the network session and identifies protected resource access privileges using scopes. A scope is a space-separated list of resource access permissions that the client web application is given permission to access. In other words, a scope determines the type of access that the access token does and does not permit. For example, if the client web application tries to make an application programming interface request for a protected resource with an access token that does not have the right scope (i.e., correct permission), then the application programming interface will deny the protected resource access request. After the client web application obtains the access token, the client web application sends the access token to the application programming interface corresponding to the protected resource. The access token is valid only for the set of operations and the protected resource described in the scopes field of the access token. For example, if the access token is issued for a calendar application programming interface, then the access token only permits access to the calendar application programming interface and does not permit access to a contacts application programming interface, for example, or any other type of application programming interface.

There is no limit to the number of scopes that can be added to an application programming interface definition of an authorization server. For example, an entity can have hundreds or thousands of scopes for accessing its protected resources. However, the number of scopes that can be included in an access token may be bound by the size of the access token when used in an authorization header (e.g., HTTP protocol). Further, most authorization servers enforce an access token size limit (e.g., <NUM>-<NUM> KB). As a result, access tokens with large scopes fields can be rejected by authentication servers. Furthermore, large access tokens can increase network latency and decrease system performance.

According to one illustrative embodiment, a computer-implemented method for access token scope limiting is provided. A computer presents an access token of a client containing a list of scopes to an authorization application programming interface of the computer. Each scope in the list of scopes defines a permission to access a particular protected resource hosted by a resource server. The computer returns a new access token to the client containing a decreased number of scopes using a scope alias in response to the authorization application programming interface requesting a decrease in a number of scopes in the list of scopes. The scope alias representing a plurality of specific scopes from the list of scopes contained in the presented access token. According to other illustrative embodiments, a computer system and computer program product for access token scope limiting are provided.

In addition, the illustrative embodiments also receive an access token request with an authorization code and a client identifier from the client via a network, determine whether scopes are specified in the access token request based on an analysis of the access token request, identify a set of scopes specified in the access token request to form a set of specified scopes in response to determining that scopes are specified in the access token request based on the analysis, expand each scope alias included in the set of specified scopes to form an expanded set of specified scopes, expand all scope aliases included in authorized scopes corresponding to the client identifier retrieved from storage to form an expanded set of authorized scopes, generate an intersection between the expanded set of specified scopes and the expanded set of authorized scopes, identify a number of valid scopes corresponding to the access token request by the client based on the intersection between the expanded set of specified scopes and the expanded set of authorized scopes, decrease the number of valid scopes corresponding to the access token request using a number of predefined scope aliases where each of the number of predefined scope aliases represents a collection of two or more client-specified individual scopes, and generate the access token for the client using the number of predefined scope aliases and any remaining valid scopes corresponding to the access token request not included in at least one of the number of predefined scope aliases.

Further, the illustrative embodiments receive a refresh token containing a list of scopes corresponding to an existing access token of the client along with a request for a new access token specifying a limited set of scopes from the client via a network where the limited set of scopes is specific to a particular set of protected resources that the client wants to access, expand each scope alias included in the list of scopes of the refresh token to form an expanded set of refresh token scopes, expand each scope alias included in the limited set of scopes specified in the request for the new access token to form an expanded set of specified scopes, generate an intersection between the expanded set of refresh token scopes and the expanded set of specified scopes, identify a number of valid scopes corresponding to the request for the new access token based on the intersection between the expanded set of refresh token scopes and the expanded set of specified scopes, decrease the number of valid scopes corresponding to the request for the new access token using one or more predefined scope aliases where each of the one or more predefined scope aliases represents a collection of two or more client-specified individual scopes, and generate the new access token for the client using the one or more predefined scope aliases and any remaining valid scopes corresponding to the request for the new access token that were not included in the one or more predefined scope aliases.

As a result, the illustrative embodiments provide a technical effect and practical application in the field of protected resource access management by decreasing a size of scopes fields in access tokens using a scope alias to represent a plurality of scopes while maintaining a same level of protected resource access permissions for the access tokens as the plurality of individual scopes that the scope alias represents. The reduced size of access tokens generated by the illustrative embodiments increases network response times, which enables faster protected resource access and increased system performance.

With reference now to the figures, and in particular, with reference to <FIG> and <FIG>, diagrams of data processing environments are provided in which illustrative embodiments may be implemented. It should be appreciated that <FIG> and <FIG> are only meant as examples and are not intended to assert or imply any limitation with regard to the environments in which different embodiments may be implemented. Many modifications to the depicted environments may be made.

<FIG> depicts a pictorial representation of a network of data processing systems in which illustrative embodiments may be implemented. Network data processing system <NUM> is a network of computers, data processing systems, and other devices in which the illustrative embodiments may be implemented. Network data processing system <NUM> contains network <NUM>, which is the medium used to provide communications links between the computers, data processing systems, and other devices connected together within network data processing system <NUM>. Network <NUM> may include connections, such as, for example, wire communication links, wireless communication links, fiber optic cables, and the like.

In the depicted example, resource server <NUM>, authorization server <NUM>, and authorization policy decision point server <NUM> connect to network <NUM>, along with storage <NUM>. Resource server <NUM>, authorization server <NUM>, and authorization policy decision point server <NUM> may be, for example, server computers with high-speed connections to network <NUM>. Also, it should be noted that resource server <NUM>, authorization server <NUM>, and authorization policy decision point server <NUM> may each represent multiple computing nodes in one or more cloud environments managed by one or more entities. Alternatively, resource server <NUM>, authorization server <NUM>, and authorization policy decision point server <NUM> may each represent one or more clusters of servers in one or more data centers.

Resource server <NUM> hosts a set of protected resources. The set of protected resources may include, for example, one or more of data, documents, files, software, hardware, services, and the like. Resource server <NUM> is capable of accepting and responding to protected resource access requests from client devices using access tokens. Access tokens contain end user or service identifiers for network sessions and identify protected resource access privileges using scopes. Scopes are space-separated lists of permissions for accessing specific protected resources. A resource owner is an entity capable of granting access to a protected resource. When the resource owner is a person, that person is referred to as an end user.

Authorization server <NUM> issues the access tokens to the client devices after successfully authenticating resource owners corresponding to the client devices. Furthermore, authorization server <NUM> limits the number of scopes in an access token by utilizing a set of scope aliases, each scope alias representing a plurality of individual scopes. A scope alias maintains the same level of access permissions for the access token as the plurality of individual scopes that the scope alias represents.

Authorization policy decision point server <NUM> stores all authorization policies. To support resource server <NUM> in protecting hosted resources, authorization policy decision point server <NUM> includes an authorization application programming interface to evaluate authorization policies corresponding to each protected resource hosted by resource server <NUM> and provide an authorization decision. It should be noted that even though authorization policy decision point server <NUM> is shown as a separate server computer in this example, in an alternative illustrative embodiment authorization policy decision point server <NUM> can be included in, or combined with, authorization server <NUM>.

Client <NUM>, client <NUM>, and client <NUM> also connect to network <NUM>. Clients <NUM>, <NUM>, and <NUM> are clients of resource server <NUM>. In this example, clients <NUM>, <NUM>, and <NUM> are shown as desktop or personal computers with wire communication links to network <NUM>. However, it should be noted that clients <NUM>, <NUM>, and <NUM> are examples only and may represent other types of data processing systems, such as, for example, network computers, laptop computers, handheld computers, smart phones, smart watches, smart televisions, smart vehicles, smart glasses, smart appliances, gaming devices, kiosks, and the like, with wire or wireless communication links to network <NUM>. Users of clients <NUM>, <NUM>, and <NUM> may utilize specific web applications loaded on clients <NUM>, <NUM>, and <NUM> to access corresponding protected resources hosted by resource server <NUM> using access tokens with appropriate scopes received from authorization server <NUM>.

Storage <NUM> is a network storage device capable of storing any type of data in a structured format or an unstructured format. In addition, storage <NUM> may represent a plurality of network storage devices. Further, storage <NUM> may store identifiers and network addresses for a plurality of resource servers, identifiers and network addresses for a plurality of different client devices, identifiers for a plurality of different users, and the like. Furthermore, storage <NUM> may store other types of data, such as authentication or credential data that may include usernames, passwords, and biometric data associated with the different users, for example.

In addition, it should be noted that network data processing system <NUM> may include any number of additional servers, clients, storage devices, and other devices not shown. Program code located in network data processing system <NUM> may be stored on a computer readable storage medium or a set of computer readable storage media and downloaded to a computer or other data processing device for use. For example, program code may be stored on a computer readable storage medium on resource server <NUM> and downloaded to client <NUM> over network <NUM> for use on client <NUM>.

In the depicted example, network data processing system <NUM> may be implemented as a number of different types of communication networks, such as, for example, an internet, an intranet, a wide area network (WAN), a local area network (LAN), a telecommunications network, or any combination thereof. <FIG> is intended as an example only, and not as an architectural limitation for the different illustrative embodiments.

As used herein, when used with reference to items, "a number of" means one or more of the items. For example, "a number of different types of communication networks" is one or more different types of communication networks. Similarly, "a set of," when used with reference to items, means one or more of the items.

Further, the term "at least one of," when used with a list of items, means different combinations of one or more of the listed items may be used, and only one of each item in the list may be needed. In other words, "at least one of" means any combination of items and number of items may be used from the list, but not all of the items in the list are required. The item may be a particular object, a thing, or a category.

This example may also include item A, item B, and item C or item B and item C. Of course, any combinations of these items may be present. In some illustrative examples, "at least one of" may be, for example, without limitation, two of item A; one of item B; and ten of item C; four of item B and seven of item C; or other suitable combinations.

With reference now to <FIG>, a diagram of a data processing system is depicted in accordance with an illustrative embodiment. Data processing system <NUM> is an example of a computer, such as authorization server <NUM> or authorization policy decision point server <NUM> in <FIG>, in which computer readable program code or instructions implementing the access management processes of illustrative embodiments may be located. In this example, data processing system <NUM> includes communications fabric <NUM>, which provides communications between processor unit <NUM>, memory <NUM>, persistent storage <NUM>, communications unit <NUM>, input/output unit <NUM>, and display <NUM>.

Processor unit <NUM> serves to execute instructions for software applications and programs that may be loaded into memory <NUM>. Processor unit <NUM> may be a set of one or more hardware processor devices or may be a multi-core processor, depending on the particular implementation.

Memory <NUM> and persistent storage <NUM> are examples of storage devices <NUM>. As used herein, a computer readable storage device or a computer readable storage medium is any piece of hardware that is capable of storing information, such as, for example, without limitation, data, computer readable program code in functional form, and/or other suitable information either on a transient basis or a persistent basis. Further, a computer readable storage device or a computer readable storage medium excludes a propagation medium, such as transitory signals. Furthermore, a computer readable storage device or a computer readable storage medium may represent a set of computer readable storage devices or a set of computer readable storage media. Memory <NUM>, in these examples, may be, for example, a random-access memory (RAM), or any other suitable volatile or non-volatile storage device, such as a flash memory. Persistent storage <NUM> may take various forms, depending on the particular implementation. For example, persistent storage <NUM> may contain one or more devices. For example, persistent storage <NUM> may be a disk drive, a solid-state drive, a rewritable optical disk, a rewritable magnetic tape, or some combination of the above. The media used by persistent storage <NUM> may be removable.

In this example, persistent storage <NUM> stores authorization application programming interface <NUM>. Authorization application programming interface <NUM> is an application programming interface for authorizing access to one or more protected resources hosted by a resource server, such as, for example, resource server <NUM> in <FIG>. In addition, it should be noted that authorization application programming interface <NUM> may represent a plurality of different authorization application programming interfaces. Further, authorization application programming interface <NUM> may be located in a plurality of data processing systems.

Communications unit <NUM>, in this example, provides for communication with other computers, data processing systems, and devices via a network, such as network <NUM> in <FIG>. Communications unit <NUM> may provide communications through the use of both physical and wireless communications links. The physical communications link may utilize, for example, a wire, cable, universal serial bus, or any other physical technology to establish a physical communications link for data processing system <NUM>. The wireless communications link may utilize, for example, shortwave, high frequency, ultrahigh frequency, microwave, wireless fidelity (Wi-Fi), Bluetooth® technology, global system for mobile communications (GSM), code division multiple access (CDMA), second-generation (<NUM>), third-generation (<NUM>), fourth-generation (<NUM>), <NUM> Long Term Evolution (LTE), LTE Advanced, fifth-generation (<NUM>), or any other wireless communication technology or standard to establish a wireless communications link for data processing system <NUM>.

Input/output unit <NUM> allows for the input and output of data with other devices that may be connected to data processing system <NUM>. For example, input/output unit <NUM> may provide a connection for user input through a keypad, a keyboard, a mouse, a microphone, and/or some other suitable input device. Display <NUM> provides a mechanism to display information to a user and may include touch screen capabilities to allow the user to make on-screen selections through user interfaces or input data, for example.

Instructions for the operating system, applications, and/or programs may be located in storage devices <NUM>, which are in communication with processor unit <NUM> through communications fabric <NUM>. In this illustrative example, the instructions are in a functional form on persistent storage <NUM>. These instructions may be loaded into memory <NUM> for running by processor unit <NUM>. The processes of the different embodiments may be performed by processor unit <NUM> using computer-implemented instructions, which may be located in a memory, such as memory <NUM>. These program instructions are referred to as program code, computer usable program code, or computer readable program code that may be read and run by a processor in processor unit <NUM>. The program instructions, in the different embodiments, may be embodied on different physical computer readable storage devices, such as memory <NUM> or persistent storage <NUM>.

Program code <NUM> is located in a functional form on computer readable media <NUM> that is selectively removable and may be loaded onto or transferred to data processing system <NUM> for running by processor unit <NUM>. Program code <NUM> and computer readable media <NUM> form computer program product <NUM>. In one example, computer readable media <NUM> may be computer readable storage media <NUM> or computer readable signal media <NUM>.

In these illustrative examples, computer readable storage media <NUM> is a physical or tangible storage device used to store program code <NUM> rather than a medium that propagates or transmits program code <NUM>. Computer readable storage media <NUM> may include, for example, an optical or magnetic disc that is inserted or placed into a drive or other device that is part of persistent storage <NUM> for transfer onto a storage device, such as a hard drive, that is part of persistent storage <NUM>. Computer readable storage media <NUM> also may take the form of a persistent storage, such as a hard drive, a thumb drive, or a flash memory that is connected to data processing system <NUM>.

Alternatively, program code <NUM> may be transferred to data processing system <NUM> using computer readable signal media <NUM>. Computer readable signal media <NUM> may be, for example, a propagated data signal containing program code <NUM>. For example, computer readable signal media <NUM> may be an electromagnetic signal, an optical signal, or any other suitable type of signal. These signals may be transmitted over communication links, such as wireless communication links, an optical fiber cable, a coaxial cable, a wire, or any other suitable type of communications link.

Further, as used herein, "computer readable media <NUM>" can be singular or plural. For example, program code <NUM> can be located in computer readable media <NUM> in the form of a single storage device or system. In another example, program code <NUM> can be located in computer readable media <NUM> that is distributed in multiple data processing systems. In other words, some instructions in program code <NUM> can be located in one data processing system while other instructions in program code <NUM> can be located in one or more other data processing systems. For example, a portion of program code <NUM> can be located in computer readable media <NUM> in a server computer while another portion of program code <NUM> can be located in computer readable media <NUM> located in a set of client computers.

The different components illustrated for data processing system <NUM> are not meant to provide architectural limitations to the manner in which different embodiments can be implemented. In some illustrative examples, one or more of the components may be incorporated in or otherwise form a portion of, another component. For example, memory <NUM>, or portions thereof, may be incorporated in processor unit <NUM> in some illustrative examples. The different illustrative embodiments can be implemented in a data processing system including components in addition to or in place of those illustrated for data processing system <NUM>. Other components shown in <FIG> can be varied from the illustrative examples shown. The different embodiments can be implemented using any hardware device or system capable of running program code <NUM>.

In another example, a bus system may be used to implement communications fabric <NUM> and may be comprised of one or more buses, such as a system bus or an input/output bus. Of course, the bus system may be implemented using any suitable type of architecture that provides for a transfer of data between different components or devices attached to the bus system.

It is understood that although this disclosure includes a detailed description on cloud computing, implementation of the teachings recited herein are not limited to a cloud computing environment. Rather, illustrative embodiments are capable of being implemented in conjunction with any other type of computing environment now known or later developed. Cloud computing is a model of service delivery for enabling convenient, on-demand network access to a shared pool of configurable computing resources, such as, for example, networks, network bandwidth, servers, processing, memory, storage, applications, virtual machines, and services, which can be rapidly provisioned and released with minimal management effort or interaction with a provider of the service.

The characteristics may include, for example, on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service. On-demand self-service allows a cloud consumer to unilaterally provision computing capabilities, such as server time and network storage, as needed automatically without requiring human interaction with the service's provider. Broad network access provides for capabilities that are available over a network and accessed through standard mechanisms that promote use by heterogeneous thin or thick client platforms, such as, for example, mobile phones, laptops, and personal digital assistants. Resource pooling allows the provider's computing resources to be pooled to serve multiple consumers using a multi-tenant model, with different physical and virtual resources dynamically assigned and reassigned according to demand. There is a sense of location independence in that the consumer generally has no control or knowledge over the exact location of the provided resources, but may be able to specify location at a higher level of abstraction, such as, for example, country, state, or data center. Rapid elasticity provides for capabilities that can be rapidly and elastically provisioned, in some cases automatically, to quickly scale out and rapidly released to quickly scale in. Measured service allows cloud systems to automatically control and optimize resource use by leveraging a metering capability at some level of abstraction appropriate to the type of service, such as, for example, storage, processing, bandwidth, and active user accounts. Resource usage can be monitored, controlled, and reported providing transparency for both the provider and consumer of the utilized service.

Service models may include, for example, Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Service (IaaS). Software as a Service is the capability provided to the consumer to use the provider's applications running on a cloud infrastructure. The applications are accessible from various client devices through a thin client interface, such as a web browser (e.g., web-based e-mail). Platform as a Service is the capability provided to the consumer to deploy onto the cloud infrastructure consumer-created or acquired applications created using programming languages and tools supported by the provider. Infrastructure as a Service is the capability provided to the consumer to provision processing, storage, networks, and other fundamental computing resources where the consumer is able to deploy and run arbitrary software, which can include operating systems and applications. The consumer does not manage or control the underlying cloud infrastructure, but has control over operating systems, storage, deployed applications, and possibly limited control of select networking components, such as, for example, host firewalls.

Deployment models may include, for example, a private cloud, community cloud, public cloud, and hybrid cloud. A private cloud is a cloud infrastructure operated solely for an organization. The private cloud may be managed by the organization or a third party and may exist on-premises or off-premises. A community cloud is a cloud infrastructure shared by several organizations and supports a specific community that has shared concerns, such as, for example, mission, security requirements, policy, and compliance considerations. The community cloud may be managed by the organizations or a third party and may exist on-premises or off-premises. A public cloud is a cloud infrastructure made available to the general public or a large industry group and is owned by an organization selling cloud services. A hybrid cloud is a cloud infrastructure composed of two or more clouds, such as, for example, private, community, and public clouds, which remain as unique entities, but are bound together by standardized or proprietary technology that enables data and application portability, such as, for example, cloud bursting for load-balancing between clouds.

At the heart of cloud computing is an infrastructure comprising a network of interconnected nodes.

With reference now to <FIG>, a diagram illustrating a cloud computing environment is depicted in which illustrative embodiments may be implemented. In this illustrative example, cloud computing environment <NUM> includes a set of one or more cloud computing nodes <NUM> with which local computing devices used by cloud consumers, such as, for example, personal digital assistant or smart phone 320A, desktop computer 320B, laptop computer 320C, and/or vehicle computer system 320N, may communicate. Cloud computing nodes <NUM> may be, for example, resource server <NUM>, authorization server <NUM>, and authorization policy decision point server <NUM> in <FIG>. Local computing devices 320A-320N may be, for example, clients <NUM>-<NUM> in <FIG>.

Cloud computing nodes <NUM> may communicate with one another and may be grouped physically or virtually into one or more networks, such as private, community, public, or hybrid clouds as described hereinabove, or a combination thereof. This allows cloud computing environment <NUM> to offer infrastructure, platforms, and/or software as services for which a cloud consumer does not need to maintain resources on a local computing device, such as local computing devices 320A-320N. It is understood that the types of local computing devices 320A-320N are intended to be illustrative only and that cloud computing nodes <NUM> and cloud computing environment <NUM> can communicate with any type of computerized device over any type of network and/or network addressable connection using a web browser, for example.

With reference now to <FIG>, a diagram illustrating abstraction model layers is depicted in accordance with an illustrative embodiment. The set of functional abstraction layers shown in this illustrative example may be provided by a cloud computing environment, such as cloud computing environment <NUM> in <FIG>. As depicted, the following layers and corresponding functions are provided.

Abstraction layers of a cloud computing environment <NUM> include hardware and software layer <NUM>, virtualization layer <NUM>, management layer <NUM>, and workloads layer <NUM>. Hardware and software layer <NUM> includes the hardware and software components of the cloud computing environment. The hardware components may include, for example, mainframes <NUM>, RISC (Reduced Instruction Set Computer) architecture-based servers <NUM>, servers <NUM>, blade servers <NUM>, storage devices <NUM>, and networks and networking components <NUM>. In some illustrative embodiments, software components may include, for example, network application server software <NUM> and database software <NUM>.

Resource provisioning <NUM> provides dynamic procurement of computing resources and other resources, which are utilized to perform tasks within the cloud computing environment. Metering and pricing <NUM> provide cost tracking as resources are utilized within the cloud computing environment, and billing or invoicing for consumption of these resources. In one example, these resources may comprise application software licenses. Service level agreement (SLA) planning and fulfillment <NUM> provides pre-arrangement for, and procurement of, cloud computing resources for which a future requirement is anticipated in accordance with an SLA.

Workloads layer <NUM> provides examples of functionality for which the cloud computing environment may be utilized. Example workloads and functions, which may be provided by workload layer <NUM>, may include mapping and navigation <NUM>, software development and lifecycle management <NUM>, virtual classroom education delivery <NUM>, data analytics processing <NUM>, transaction processing <NUM>, and protected resource access management <NUM>.

Token-based authorization systems (e.g., OAuth <NUM>) define authorization using scopes (i.e., an arbitrary string of characters or keywords). A scope defines access permission to a set of protected resources. Scopes are usually not standardized; each authorization system defines its own set of scopes. A typical set of scopes may be, for example, uaa. write, uaa. admin, cloud_controller. read, cloud_controller. write, and cloud_controller. The list of scopes gets longer the more authorizations that correspond to an end user or service. With the increasing size of the list of scopes, access tokens also get larger and larger making invocations (e.g., protected resource access requests) via networks slower due to increased latency. For example, each character used for a scope results in <NUM> characters in an access token. For example, the scope cloud_controller. scim clients. read includes <NUM> characters, which results in approximately <NUM> characters in the access token. An authorization server may implement token scope character limits (i.e., a character length limit on the scopes field can be assigned against generated access tokens). For example, an authorization server can return invalid_scope when the size of an access token's scopes field is greater than or equal to the set maximum size threshold limit (e.g., <NUM> KB). In other words, too many scopes included in an access token can result in an error being thrown.

Illustrative embodiments utilize scopes in a very limited way (i.e., the authorization server is implemented with a separate set of application programming interfaces). Scopes are a high-level authorization filter (i.e., for each available protected resource (e.g., service) in the cloud, there is one scope that limits the permission of an access token to one specific protected resource only). Typically, an end user that logs in via a graphical user interface or command line interface receives an access token that has the authorization to access all protected resources (e.g., services) of an entity, such as, for example, an enterprise, company, business, organization, institution, agency, or the like. An entity can have hundreds or thousands of scopes for different protected resources. As a result, each access token can contain the full list of protected resource scopes making these access tokens very large (e.g., > <NUM> KB), which decreases system performance by increasing network latency and increases access token rejection rates (i.e., errors being thrown) by authentication servers. Illustrative embodiments utilize scope aliases to decrease the size of access tokens (i.e., scopes fields), which increases system performance by decreasing network response times (i.e., decreased time to access protected resources) and decreases access token rejection rates by authentication servers, while maintaining the same level of access permissions for the access tokens. As used herein, one scope alias represents a plurality of individual scopes.

Thus, illustrative embodiments provide one or more technical solutions that overcome a technical problem with access tokens with large scopes fields (e.g., <NUM> KB or greater in size), which cause decreased network response times, decreased system performance, and increased rejection rates of protected resource access requests (e.g., errors) by network switches, routers, servers, and the like. As a result, these one or more technical solutions provide a technical effect and practical application in the field of protected resource access management by decreasing a size of scopes fields in access tokens using a scope alias to represent a plurality of scopes while maintaining a same level of protected resource access permissions for the access tokens as the plurality of individual scopes that the scope alias represents. The reduced size of access tokens generated by illustrative embodiments improves/decreases network response times, which enables faster protected resource access and increased system performance.

With reference now to <FIG>, a diagram illustrating an example of scope aliases is depicted in accordance with an illustrative embodiment. Scope aliases <NUM> are a set of scope aliases, each scope alias in the set represents a plurality or collection of specific individual scopes. For example, scope aliases <NUM> represent corresponding scopes <NUM>.

In this example, scope aliases <NUM> include scope alias "ALL" <NUM>, scope alias "GROUP1" <NUM>, and scope alias "GROUP2" <NUM>. Scope alias "ALL" <NUM> represents the individual scopes of "SERVICE1" <NUM>, "SERVICE2" <NUM>, "SERVICE3" <NUM>, "SERVICE4" <NUM>, "SERVICE5" <NUM>, and "SERVICE6" <NUM>. Scope alias "GROUP1" <NUM> represents the individual scopes of "SERVICE1" <NUM>, "SERVICE2" <NUM>, "SERVICE3" <NUM>, and "SERVICE4" <NUM>. Scope alias "GROUP2" <NUM> represents the individual scopes of "SERVICE5" <NUM> and "SERVICE6" <NUM>. It should be noted that each of the listed services above is a protected resource hosted by a resource server, such as, for example, resource server <NUM> in <FIG>.

When an authorization server, such as, for example, authorization server <NUM> in <FIG>, places scope alias "ALL" <NUM> in a scopes field of a generated access token, that particular access token has the same level of access permissions as all of the individual scopes "SERVICE1" <NUM>, "SERVICE2" <NUM>, "SERVICE3" <NUM>, "SERVICE4" <NUM>, "SERVICE5" <NUM>, and "SERVICE6" <NUM>, while decreasing the size of the scopes field. Similarly, when the authorization places scope alias "GROUP1" <NUM> in a scopes field of a generated access token, that particular access token has the same level of access permissions as individual scopes "SERVICE1" <NUM>, "SERVICE2" <NUM>, "SERVICE3" <NUM>, and "SERVICE4" <NUM>, while limiting the size of the scopes field. Also, when the authorization places scope alias "GROUP2" <NUM> in a scopes field of a generated access token, that particular access token has the same level of access permissions as individual scopes "SERVICE5" <NUM> and "SERVICE6" <NUM>.

With reference now to <FIG>, a diagram illustrating an example of client identifiers with corresponding scopes is depicted in accordance with an illustrative embodiment. In this example, client identifiers with corresponding scopes <NUM> include client identifier "CLIENT1" <NUM> and client identifier "CLIENT2" <NUM>.

Client identifier "CLIENT1" <NUM> is associated with scope alias "ALL" <NUM>, such as, for example, scope alias "ALL" <NUM> in <FIG>. Scope alias "ALL" <NUM> represents corresponding scopes <NUM>. Corresponding scopes <NUM> include "SERVICE1" <NUM>, "SERVICE2" <NUM>, "SERVICE3" <NUM>, "SERVICE4" <NUM>, "SERVICE5" <NUM>, and "SERVICE6" <NUM>, such as, for example, "SERVICE1" <NUM>, "SERVICE2" <NUM>, "SERVICE3" <NUM>, "SERVICE4" <NUM>, "SERVICE5" <NUM>, and "SERVICE6" <NUM> in <FIG>. Thus, when an authorization server, such as, for example, authorization server <NUM> in <FIG>, expands scope alias "ALL" <NUM>, which is specified in an access token request by a client or included in a scopes field of a received access token, the result of the expansion is "SERVICE1" <NUM>, "SERVICE2" <NUM>, "SERVICE3" <NUM>, "SERVICE4" <NUM>, "SERVICE5" <NUM>, and "SERVICE6" <NUM>.

Client identifier "CLIENT2" <NUM> is associated with scope "SERVICE1" <NUM> and scope alias "GROUP2" <NUM>, such as, for example, scope alias "GROUP2" <NUM> in <FIG>. Scope alias "GROUP2" <NUM> represents a portion of corresponding scopes <NUM>. Corresponding scopes <NUM> include "SERVICE1" <NUM>, "SERVICE5" <NUM>, and "SERVICE6" <NUM>. When the authorization server expands scope alias "GROUP2" <NUM>, which is specified in an access token request by a client or included in a scopes field of a received access token, the result of the expansion is "SERVICE5" <NUM> and "SERVICE6" <NUM>.

With reference now to <FIG>, a diagram illustrating an example process for obtaining an access token is depicted in accordance with an illustrative embodiment. Obtaining access token process <NUM> may be implemented in a network of data processing systems, such as, for example, network data processing system <NUM> in <FIG> or a cloud computing environment, such as, for example, cloud computing environment <NUM> in <FIG>. In this example, obtaining access token process <NUM> includes resource owner <NUM>, client <NUM>, and authorization server <NUM>. Client <NUM> may be, for example, client <NUM> in <FIG> or local computing device 320A in <FIG>. Authorization server <NUM> may be, for example, authorization server <NUM> in <FIG>, data processing system <NUM> in <FIG>, or a cloud computing node in cloud computing nodes <NUM> in <FIG>. However, it should be noted that obtaining access token process <NUM> may include any number of resource owners, clients, and authorization servers. In other words, obtaining access token process <NUM> is intended as an example only and not as a limitation on illustrative embodiments.

At <NUM>, resource owner <NUM> (e.g., an end user) starts a web application on client <NUM> for accessing a set of protected resources. The set of protected resources may be, for example, a set of one or more cloud services. At <NUM>, client <NUM> redirects to authorization server <NUM>. At <NUM>, resource owner <NUM> sends an authorization request to authorization server <NUM>. At <NUM>, authorization server <NUM> displays a login page to resource owner <NUM>. At <NUM>, resource owner <NUM> provides credentials (e.g., username and password) to authorization server <NUM> via the login page.

At <NUM>, authorization server <NUM> validates the credentials provided by resource owner <NUM>. At <NUM>, upon successful validation of the credentials, authorization server <NUM> redirects to the web application of client <NUM> with an authorization code as part of the redirect information to resource owner <NUM>. At <NUM>, resource owner <NUM> provides the authorization code to client <NUM>.

At <NUM>, client <NUM> requests an access token from authorization server <NUM> using the authorization code and optionally specifies scopes in the access token request for accessing the set of protected resources. At <NUM>, authorization server <NUM> validates the specified scopes in the access token request or, if no scopes were specified in the access token request, authorization server <NUM> retrieves authorized scopes corresponding to the client from storage.

A specific illustrative example for scope handling according to OAuth <NUM> when scope aliasing is supported is described here. The web application of client <NUM> (e.g., the web application corresponding to client identifier <NUM> in <FIG>) has the following scope alias "ALL" (e.g., scope alias <NUM> in <FIG>), which is equivalent to the specific individual scopes of SERVICE1, SERVICE2, SERVICE3, SERVICE4, SERVICE5, and SERVICE6 (e.g., scopes <NUM>-<NUM> in <FIG>). Scenario <NUM>, client <NUM> does not specify any scopes in the access token request. As a result, authorization server <NUM> retrieves all authorized scopes (i.e., SERVICE1, SERVICE2, SERVICE3, SERVICE4, SERVICE5, SERVICE6) corresponding to client <NUM> from storage. Authorization server <NUM> then limits the number of scopes for the scopes field of the access token using the scope alias "ALL" to represent the individual scopes of SERVICE1, SERVICE2, SERVICE3, SERVICE4, SERVICE5, AND SERVICE6, while maintaining the same level of permissions for the access token. Scenario <NUM>, client <NUM> does specify particular scopes, such as SERVICE1, SERVICE5, and SERVICE6 (e.g., scopes <NUM>-<NUM> in <FIG>), in the access token request. Alternatively, client <NUM> uses a combination of individual scopes with one or more scope aliases (e.g., SERVICE1, GROUP2, such as scope <NUM> and scope alias <NUM> in <FIG>) in the access token request. Authorization server <NUM> then returns all valid client scopes (e.g., SERVICE1, SERVICE5, SERVICE6) or alternatively, using a scope in combination with a scope alias (e.g., SERVICE1, GROUP2) for generating the access token.

At <NUM>, authorization server <NUM> generates the access token and a refresh token for the client with resolved (i.e., authorized or valid) scopes and sends the access token to client <NUM>. At <NUM>, client <NUM> stores the access token and refresh token in the current browser session. At <NUM>, client <NUM> displays the web application to resource owner <NUM> for accessing the set of protected resources.

With reference now to <FIG>, a diagram illustrating an example process for limiting scopes of an existing access token is depicted in accordance with an illustrative embodiment. Limiting scopes of existing access token process <NUM> may be implemented in a network of data processing systems, such as, for example, network data processing system <NUM> in <FIG> or a cloud computing environment, such as, for example, cloud computing environment <NUM> in <FIG>. In this example, limiting scopes of existing access token process <NUM> includes resource owner <NUM>, client <NUM>, and authorization server <NUM>. Client <NUM> may be, for example, client <NUM> in <FIG> or local computing device 320A in <FIG>. Authorization server <NUM> may be, for example, authorization server <NUM> in <FIG>, data processing system <NUM> in <FIG>, or a cloud computing node in cloud computing nodes <NUM> in <FIG>. However, it should be noted that limiting scopes of existing access token process <NUM> may include any number of resource owners, clients, and authorization servers. In other words, limiting scopes of existing access token process <NUM> is intended as an example only and not as a limitation on illustrative embodiments.

At <NUM>, resource owner <NUM> (e.g., an end user) requests execution of a set of actions on a protected resource. The protected resource may be, for example, a service, such as a database service. The set of actions may be, for example, one or more of create, read, update, delete, and the like. At <NUM>, client <NUM> (e.g., a web application on client <NUM>) requests a new access token with a limited set of scopes that specifically permit execution of only those actions included in the set of actions. At <NUM>, client <NUM> sends a refresh token containing a list of scopes of client <NUM>. At <NUM>, authorization server <NUM> validates the limited set of scopes specified for the new access token using the list of scopes contained in the refresh token.

A specific illustrative example for scope handling according to OAuth <NUM> when scope aliasing is supported is described here. The refresh token of client <NUM> contains a list of individual scopes of SERVICE1, SERVICE2, SERVICE3, SERVICE4, SERVICE5, and SERVICE6 (e.g., scopes <NUM>-<NUM> in <FIG>) or the equivalent scope alias "ALL" (e.g., scope alias <NUM> in <FIG>). Client <NUM> specifies a particular limited set of individual scopes, such as SERVICE1, SERVICE5, and SERVICE6 (e.g., scopes <NUM>-<NUM> in <FIG>), in the request for the new access token. Alternatively, client <NUM> specifies the limited set of scopes using a combination of an individual scope with a scope alias (e.g., SERVICE1, GROUP2, such as scope <NUM> and scope alias <NUM> in <FIG>) in the request for the new access token. Authorization server <NUM> then validates the limited set of scopes (e.g., SERVICE1, SERVICE5, SERVICE6 or SERVICE1, GROUP2) based on the list of scopes contained in the refresh token. It should be noted that if the limited set of scopes contains a scope alias (e.g., GROUP2), then authorization server <NUM> expands the scope alias to its corresponding individual scopes (e.g., SERVICE5, SERVICE6) before performing the scope validation process using the list of scopes contained in the refresh token. In response to validating the limited set of scopes specified in the request for the new access token, authorization server <NUM> returns SERVICE1, GROUP2 (i.e., SERVICE1, SERVICE5, SERVICE6) for generating the new access token and refresh token for client <NUM>. Using the combination of scope and scope alias for the new access token decreases the size of the scopes field as opposed to using all of the individual scopes specified in the limited set of scopes.

At <NUM>, authorization server <NUM> generates the new access token and a new refresh token with the limited set of scopes and sends the new access token and the new refresh token to client <NUM>. At <NUM>, client <NUM>, using the new access token with the limited set of scopes, invokes one or more application programming interfaces to execute the set of actions. At <NUM>, client <NUM> displays a result of the set of actions to resource owner <NUM> via the web application.

With reference now to <FIG>, a diagram illustrating an example process for accessing a protected resource is depicted in accordance with an illustrative embodiment. Accessing protected resource process <NUM> may be implemented in a network of data processing systems, such as, for example, network data processing system <NUM> in <FIG> or a cloud computing environment, such as, for example, cloud computing environment <NUM> in <FIG>. In this example, accessing protected resource process <NUM> includes client <NUM>, resource server <NUM>, authorization policy decision point server <NUM>, and authorization server <NUM>. Client <NUM> may be, for example, client <NUM> in <FIG> or local computing device 320A in <FIG>. Resource server <NUM> may be, for example, resource server <NUM> in <FIG> or a cloud computing node in cloud computing nodes <NUM> in <FIG>, which hosts a set of one or more protected resources. For example, resource server <NUM> may be a database containing sensitive data of a resource owner. Authorization policy decision point server <NUM> may be, for example, authorization policy decision point server <NUM> in <FIG> or another cloud computing node in cloud computing nodes <NUM> in <FIG>, which provides access authorization decisions based on authorization policies corresponding to resource server <NUM>. Authorization server <NUM> may be, for example, authorization server <NUM> in <FIG>, data processing system <NUM> in <FIG>, or yet another cloud computing node in cloud computing nodes <NUM> in <FIG>. However, it should be noted that in an alternative illustrative embodiment, authorization policy decision point server <NUM> and authorization server <NUM> may be located on the same server. Moreover, accessing protected resource process <NUM> may include any number of clients, resource servers, authorization policy decision point servers, and authorization servers. In other words, accessing protected resource process <NUM> is intended as an example only and not as a limitation on illustrative embodiments.

At <NUM>, client <NUM> (e.g., a web application on client <NUM>) calls an application programming interface on resource server <NUM> with an access token of client <NUM> requesting access to a protected resource hosted by resource server <NUM>. At <NUM>, resource server <NUM> checks with authorization policy decision point server <NUM> as to whether the application programming interface call is permitted based on the protected resource requested and scopes contained in the access token of client <NUM>. At <NUM>, authorization policy decision point server <NUM> asks authorization server <NUM> to determine whether a scope required to access the protected resource hosted by resource server <NUM> is contained in the access token of client <NUM>.

At <NUM>, authorization server <NUM> expands each scope alias contained in the access token of client <NUM> to individual scopes represented by each scope alias and checks whether the required scope is present. At <NUM>, authorization server <NUM> returns "TRUE" when the required scope to access the protected resource is present. Otherwise, authorization server <NUM> returns "FALSE" when the required scope to access the protected resource is not present. At <NUM>, when the required scope to access the protected resource is present, authorization policy decision point server <NUM>, continues evaluation of authorization policies corresponding to resource server <NUM>. Alternatively, when the required scope to access the protected resource is not present, authorization server <NUM> returns "DENY".

At <NUM>, authorization policy decision point server <NUM> sends a protected resource access decision to resource server <NUM> based on the scope evaluation and authorization policy evaluation. At <NUM>, resource server <NUM> executes the application programming interface call when the application programming interface call is permitted based on the resource access decision received from authorization policy decision point server <NUM>. Alternatively, resource server <NUM> prepares an error message when the application programming interface call is not permitted based on the resource access decision received from authorization policy decision point server <NUM>. At <NUM>, resource server <NUM> sends either the result of executing the application programming interface call or the error message to client <NUM>.

With reference now to <FIG>, a flowchart illustrating a process for generating an access token is shown in accordance with an illustrative embodiment. The process shown in <FIG> may be implemented in a computer, such as, for example, authorization server <NUM> in <FIG> or data processing system <NUM> in <FIG>.

The process begins when the computer receives an access token request with an authorization code and a client identifier from a client via a network (step <NUM>). The client identifier uniquely identifies the client sending the access token request. The computer analyzes the access token request and makes a determination as to whether scopes are specified in the access token request based on the analysis (step <NUM>). A scope defines a permission to access a particular protected resource or a particular set of protected resources. A protected resource may be, for example, a cloud service, such as a database service, a storage service, a data processing service, an application service, a platform service, an infrastructure service, or the like.

If the computer determines that scopes are not specified in the access token request based on the analysis, no output of step <NUM>, then the computer retrieves all authorized scopes corresponding to the client identifier from storage to form a set of specified scopes (step <NUM>). Thereafter, the process proceeds to step <NUM>. If the computer determines that scopes are specified in the access token request based on the analysis, yes output of step <NUM>, then the computer identifies a set of scopes specified in the access token request to form a set of specified scopes (step <NUM>).

The computer expands each scope alias included in the set of specified scopes to form an expanded set of specified scopes (step <NUM>). In other words, the expanded set of specified scopes does not contain any scope aliases, but only individual scopes. In addition, the computer expands all scope aliases included in authorized scopes corresponding to the client identifier retrieved from storage to form an expanded set of authorized scopes (step <NUM>). Similarly, the expanded set of authorized scopes does not contain any scope aliases, but only individual scopes.

The computer generates an intersection between the expanded set of specified scopes and the expanded set of authorized scopes (step <NUM>). Further, the computer identifies a number of valid scopes corresponding to the access token request by the client based on the intersection between the expanded set of specified scopes and the expanded set of authorized scopes (step <NUM>). Furthermore, the computer decreases the number of valid scopes corresponding to the access token request using a number of predefined scope aliases (step <NUM>). Each of the number of predefined scope aliases represents a collection of two or more client-specified individual scopes. In other words, the computer knows which group of individual scopes to include in a particular scope alias.

Afterward, the computer generates an access token for the client using the number of predefined scope aliases and any remaining valid scopes corresponding to the access token request not included in at least one of the number of predefined scope aliases (step <NUM>). Then, the computer sends the access token to the client via the network (step <NUM>). Thereafter, the process terminates.

With reference now to <FIG>, a flowchart illustrating a process for limiting a number of scopes of an existing access token is shown in accordance with an illustrative embodiment. The process shown in <FIG> may be implemented in a computer, such as, for example, authorization server <NUM> in <FIG> or data processing system <NUM> in <FIG>.

The process begins when the computer receives a refresh token containing a list of scopes corresponding to an existing access token of a client along with a request for a new access token specifying a limited set of scopes from the client via a network (step <NUM>). The limited set of scopes is specific to a particular set of protected resources that the client wants to access. The computer expands each scope alias included in the list of scopes of the refresh token to form an expanded set of refresh token scopes (step <NUM>). In other words, the expanded set of refresh token scopes does not include any scope aliases, but only individual scopes. In addition, the computer expands each scope alias included in the limited set of scopes specified in the request for the new access token to form an expanded set of specified scopes (step <NUM>). Similarly, the expanded set of specified scopes does not include any scope aliases, but only individual scopes.

The computer generates an intersection between the expanded set of refresh token scopes and the expanded set of specified scopes (step <NUM>). Further, the computer identifies a number of valid scopes corresponding to the request for the new access token based on the intersection between the expanded set of refresh token scopes and the expanded set of specified scopes (step <NUM>). Furthermore, the computer decreases the number of valid scopes corresponding to the request for the new access token using one or more predefined scope aliases (step <NUM>). Each of the one or more predefined scope aliases represents a collection of two or more client-specified individual scopes. In other words, the computer knows which group of individual scopes to include in a particular scope alias.

Subsequently, the computer generates the new access token for the client using the one or more predefined scope aliases and any remaining valid scopes corresponding to the request for the new access token that were not included in the one or more predefined scope aliases (step <NUM>). The computer then sends the new access token and refresh token to the client via the network (step <NUM>). Thereafter, the process terminates.

With reference now to <FIG>, a flowchart illustrating a process for determining access to a protected resource by a client is shown in accordance with an illustrative embodiment. The process shown in <FIG> may be implemented in a computer, such as, for example, authorization server <NUM> data processing system <NUM> in <FIG>.

The process begins when the computer receives a request to grant access to a protected resource hosted by a resource server along with an access token of a client that includes one or more scopes from the resource server via a network (step <NUM>). The computer expands each scope alias included in the one or more scopes of the access token to form an expanded set of access token scopes (step <NUM>). In other words, the expanded set of access token scopes does not contain any scope aliases, but only individual scopes.

The computer analyzes the expanded set of access token scopes and makes a determination as to whether the expanded set of access token scopes contains a scope that grants access to the protected resource (step <NUM>). If the computer determines that the expanded set of access token scopes does not contain a scope that grants access to the protected resource, no output of step <NUM>, then the computer sends an indication to the resource server that access to the protected resource by the client is denied (step <NUM>). Thereafter, the process terminates. If the computer determines that the expanded set of access token scopes does contain a scope that grants access to the protected resource, yes output of step <NUM>, then the computer retrieves a set of authorization policies corresponding to the protected resource hosted by the resource server (step <NUM>).

Afterward, the computer makes a determination as to whether the set of authorization policies grants access to the protected resource by the client (step <NUM>). If the computer determines that the set of authorization policies does not grant access to the protected resource by the client, no output of step <NUM>, then the process returns to step <NUM> where the computer sends an indication to the resource server that access to the protected resource by the client is denied. If the computer determines that the set of authorization policies does grant access to the protected resource by the client, yes output of step <NUM>, then the computer sends an indication to the resource server that access to the protected resource by the client is granted (step <NUM>). Thereafter, the process terminates.

With reference now to <FIG>, a flowchart illustrating a process for managing a size of an access token is shown in accordance with an illustrative embodiment. The process shown in <FIG> may be implemented in a computer, such as, for example, authorization server <NUM> in <FIG> or data processing system <NUM> in <FIG>.

The process begins when the computer presents an access token of a client containing a list of scopes to an authorization application programming interface of the computer (step <NUM>). Each scope in the list of scopes defines a permission to access a particular protected resource hosted by a resource server. The computer returns a new access token to the client containing a decreased number of scopes using a scope alias in response to the authorization application programming interface requesting a decrease in a number of scopes in the list of scopes (step <NUM>). The scope alias represents a plurality of specific scopes from the list of scopes contained in the presented access token. The authorization application programming interface knows which individual scopes to include in the scope alias for a particular set of protected resources that the client is requesting access. By the computer decreasing the number of scopes using the scope alias, the computer reduces the size of a scopes field of the access token generated by the computer, which decreases the size of the access token. Decreasing the size of the access token increases network response time causing decreased time to access the protected resources and increased system performance. Thereafter, the process terminates.

Claim 1:
A computer-implemented method for access token scope limiting, the computer-implemented method comprising:
presenting, by a computer, an access token of a client containing a list of scopes to an authorization application programming interface of the computer, each scope in the list of scopes defining a permission to access a particular protected resource hosted by a resource server; and
returning, by the computer, a new access token to the client containing a decreased number of scopes using a scope alias in response to the authorization application programming interface requesting a decrease in a number of scopes in the list of scopes, the scope alias representing a plurality of specific scopes from the list of scopes contained in the presented access token.