Patent Publication Number: US-2022229928-A1

Title: Multi-Tenant Data Protection Using Tenant-Based Token Validation and Data Encryption

Description:
FIELD 
     The field relates generally to information processing systems and more particularly, to the protection of data in such information processing systems. 
     BACKGROUND 
     Data protection techniques are often employed to secure data. A multi-tenant storage environment provides storage for multiple customers or “tenants” of a storage service provider. Many organizations do not trust a multi-tenant storage environment for the storage of sensitive information. Such organizations fear threats, for example, from another tenant of a given multi-tenant storage environment. 
     A need exists for improved techniques for protecting data in a multi-tenant storage environment. 
     SUMMARY 
     In one embodiment, a method comprises obtaining, from a user, (i) at least one data record to be stored in a multi-tenant storage environment, and (ii) a token associated with the user, wherein each data record identifies a tenant associated with the respective data record and wherein the user is authorized to access tenant data of at least one tenant identified in the token; obtaining an encryption key of the tenant associated with the at least one data record; encrypting the at least one data record using the obtained encryption key; and storing the encrypted at least one data record. 
     In some embodiments, a given data record is read by obtaining a decryption key of the tenant associated with the given data record and decrypting the given data record using the decryption key. The token may be used to evaluate whether the user is authorized to access the tenant data of the tenant associated with the given data record. 
     Other illustrative embodiments include, without limitation, apparatus, systems, methods and computer program products comprising processor-readable storage media. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an information processing system configured for multi-tenant data protection using tenant-based token validation and data encryption in accordance with an illustrative embodiment; 
         FIG. 2A  is a flow diagram illustrating an exemplary implementation of a multi-tenant data storage process that uses tenant-based token validation and data encryption, according to one embodiment; 
         FIG. 2B  illustrates an exemplary set of data records to be stored using the multi-tenant data storage process of  FIG. 2A , according to some embodiments of the disclosure; 
         FIG. 2C  illustrates an exemplary access token for use in a multi-tenant storage environment, according to one or more embodiments of the disclosure; 
         FIG. 3A  is a flow diagram illustrating an exemplary implementation of a multi-tenant data read process that uses tenant-based token validation and data decryption, according to at least one embodiment; 
         FIG. 3B  illustrates an access token received from another exemplary user in a multi-tenant storage environment in conjunction with the read process of  FIG. 3A , according to one or more embodiments of the disclosure; 
         FIG. 3C  illustrates an exemplary set of data records stored in a multi-tenant storage environment, according to some embodiments; 
         FIGS. 3D and 3E  illustrate exemplary sets of data records returned from the data records of  FIG. 3C  in response to various read requests using the read process of  FIG. 3A , according to some embodiments; 
         FIG. 4  is a flow diagram illustrating an exemplary implementation of a multi-tenant data storage process using tenant-based token validation and data encryption, according to at least some embodiments; 
         FIG. 5  illustrates an exemplary processing platform that may be used to implement at least a portion of one or more embodiments of the disclosure comprising a cloud infrastructure; and 
         FIG. 6  illustrates another exemplary processing platform that may be used to implement at least a portion of one or more embodiments of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Illustrative embodiments of the present disclosure will be described herein with reference to exemplary communication, storage and processing devices. It is to be appreciated, however, that the disclosure is not restricted to use with the particular illustrative configurations shown. One or more embodiments of the disclosure provide methods, apparatus and computer program products for multi-tenant data protection using tenant-based token validation and data encryption. 
     In one or more embodiments, techniques are provided for the protection of data in a multi-tenant storage environment by employing a token that identifies one or more tenants for which a user is authorized to access the data of the identified tenants. It is to be appreciated that the term “tenant” as used herein is intended to be broadly construed so as to encompass any group of users, such as a customer of a storage service provider, users of a business entity (e.g., users in a department of a company or an academic institution), users of an organization (e.g., users in a particular company, enterprise or non-profit entity), users of a given role, as well as various combinations of such entities. 
     A token comprises an object representing that a given user has been authenticated and is typically generated upon a successful authentication of the given user. In some embodiments, a new token is generated for each session of the given user, indicating the current tenant access authorizations of the given user. It is noted that in one or more embodiments a given user may inherit the authorizations or privileges of one or more user groups to which the given user belongs. 
     In at least some embodiments, the disclosed tenant-based token validation techniques can evaluate a token, for example, in conjunction with a read or write request, to determine whether a given user is authorized to access the data of a given tenant associated with the read or write request. In addition, the disclosed tenant-based data encryption techniques are employed to encrypt data being stored using an encryption key of the tenant associated with the data being stored. Likewise, a given stored data record can be read (for example, by a user with the appropriate tenant-based token credentials) by decrypting the given stored data record using a decryption key of the tenant associated with the given stored data record. 
     Data in transit comprises data being moved between locations, such as over a network. Data protection measures for data in transit are important, as data is typically considered to be exposed to attackers while the data is in motion. Data at rest comprises data that is not actively moving, such as stored data. Data protection measures for data at rest are also important as data at rest may also be considered a valuable target to an attacker. 
     Role-based access control (RBAC) assigns various permissions to users based on the role of each user within an organization. Users can be grouped into roles, for example, based on common responsibilities and needs. Users are assigned one or more roles and each role can be assigned one or more permissions or privileges. RBAC mechanisms are often implemented using tokens. For example, a request to access information by a given user can be verified using a token that identifies the permissions of the given user. 
       FIG. 1  shows a computer network (also referred to herein as an information processing system)  100  configured in accordance with an illustrative embodiment. The computer network  100  comprises a plurality of user devices  102 - 1  through  102 -P, collectively referred to herein as user devices  102 . The user devices  102  are coupled to a network  104 , where the network  104  in this embodiment is assumed to represent a sub-network or other related portion of the larger computer network  100 . Accordingly, elements  100  and  104  are both referred to herein as examples of “networks” but the latter is assumed to be a component of the former in the context of the  FIG. 1  embodiment. Also coupled to network  104  is a private cloud platform  105  and one or more public cloud platforms  120 - 1  through  120 -N (hereinafter, collectively referred to as cloud platforms  120 ). 
     The user devices  102  may comprise, for example, host devices and/or devices such as mobile telephones, laptop computers, tablet computers, desktop computers or other types of computing devices. Such devices are examples of what are more generally referred to herein as “processing devices.” Some of these processing devices are also generally referred to herein as “computers.” The user devices  102  may comprise a network client that includes networking capabilities such as ethernet, Wi-Fi, etc. When the user devices  102  are implemented as host devices, the host devices may illustratively comprise servers or other types of computers of an enterprise computer system, cloud-based computer system or other arrangement of multiple compute nodes associated with respective users. 
     For example, the host devices in some embodiments illustratively provide compute services such as execution of one or more applications on behalf of each of one or more users associated with respective ones of the host devices. Such applications illustratively generate input-output (IO) operations that are processed by a storage system. The term “input-output” as used herein refers to at least one of input and output. For example, IO operations may comprise write requests and/or read requests directed to logical addresses of a particular logical storage volume of the storage system. These and other types of IO operations are also generally referred to herein as IO requests. 
     The user devices  102  in some embodiments comprise respective processing devices associated with a particular company, organization or other enterprise or group of users. In addition, at least portions of the computer network  100  may also be referred to herein as collectively comprising an “enterprise network.” Numerous other operating scenarios involving a wide variety of different types and arrangements of processing devices and networks are possible, as will be appreciated by those skilled in the art. 
     Also, it is to be appreciated that the term “user” in this context and elsewhere herein is intended to be broadly construed so as to encompass, for example, human, hardware, software or firmware entities, as well as various combinations of such entities. Compute and/or storage services may be provided for users under a Platform-as-a-Service (PaaS) model, an Infrastructure-as-a-Service (IaaS) model and/or a Function-as-a-Service (FaaS) model, although it is to be appreciated that numerous other cloud infrastructure arrangements could be used. Also, illustrative embodiments can be implemented outside of the cloud infrastructure context, as in the case of a stand-alone computing and storage system implemented within a given enterprise. 
     In at least some embodiments, the private cloud platform  105  further comprises a tenant-based data storage module  112 , a tenant-based data access module  114 , and a user interface  116 . The tenant-based data storage module  112  and the tenant-based data access module  114  can be used by a given tenant, for example, to write data of the given tenant to, and read data of the given tenant from, respectively, one or more public cloud platforms  120  using the disclosed tenant-based techniques. In one variation, the functionality of the tenant-based data storage module  112  and/or the tenant-based data access module  114 , or portions thereof, can be provided by a given user device  102  attempting to write tenant data to, and/or read tenant data from, one or more storage devices  130  on the public cloud platforms  120 , as discussed below. 
     It is to be appreciated that this particular arrangement of modules  112  and  114  illustrated in the private cloud platform  105  of the  FIG. 1  embodiment is presented by way of example only, and alternative arrangements can be used in other embodiments. For example, the functionality associated with modules  112  and  114  in other embodiments can be combined into a single module, or separated across a larger number of modules. As another example, multiple distinct processors can be used to implement different ones of modules  112  and  114  or portions thereof. 
     At least portions of modules  112  and  114  may be implemented at least in part in the form of software that is stored in memory and executed by a processor. An exemplary process utilizing modules  112  and  114  of an example private cloud platform  105  in computer network  100  will be described in more detail with reference to the flow diagrams of, for example,  FIGS. 2A, 3A and 4 . 
     The user devices  102  and the private cloud platform  105  may be implemented on a common processing platform, or on separate processing platforms. 
     The public cloud platforms  120  illustratively comprise processing devices of one or more processing platforms. For example, the public cloud platforms  120  can comprise one or more processing devices each having a processor and a memory, possibly implementing virtual machines and/or containers, although numerous other configurations are possible. 
     The public cloud platforms  120  can be part of cloud infrastructure such as an Amazon Web Services (AWS) system. Other examples of cloud-based systems that can be used to provide at least portions of the public cloud platforms  120  include Google Cloud Platform (GCP), Microsoft Azure, Dell Technologies Cloud, IBM Cloud, Alibaba Cloud and HPe (Hewlett Packard Enterprise) Cloud. 
     The public cloud platforms  120  each comprise one or more storage devices  130 - 1  through  130 -N. The storage devices  130  store data of a plurality of storage volumes, such as respective logical units (LUNs) or other types of logical storage volumes. The term “storage volume” as used herein is intended to be broadly construed, and should not be viewed as being limited to any particular format or configuration. 
     In the example of  FIG. 1 , each public cloud platform  120  further comprises a tenant-based data protection storage module  122  and a tenant-based data protection access module  124 . The tenant-based data protection storage module  122  and the tenant-based data protection access module  124  can be used by a given public cloud platform  120 , for example, to process requests from a given tenant to write data to, and process requests from a given tenant to read data from, respectively, the respective public cloud platform  120  using the disclosed tenant-based techniques. 
     It is to be appreciated that this particular arrangement of modules  122  and  124  illustrated in the public cloud platform  120  of the  FIG. 1  embodiment is presented by way of example only, and alternative arrangements can be used in other embodiments. For example, the functionality associated with modules  122  and  124  in other embodiments can be combined into a single module, or separated across a larger number of modules. As another example, multiple distinct processors can be used to implement different ones of modules  122  and  124  or portions thereof. 
     At least portions of modules  122  and  124  may be implemented at least in part in the form of software that is stored in memory and executed by a processor. An exemplary process utilizing modules  122  and  124  of an example public cloud platform  120  in computer network  100  will be described in more detail with reference to the flow diagrams of, for example,  FIGS. 2A, 3A and 4 . 
     The storage devices  130  of the public cloud platforms  120  illustratively comprise solid state drives (SSDs). Such SSDs are implemented using non-volatile memory (NVM) devices such as flash memory. Other types of NVM devices that can be used to implement at least a portion of the storage devices  130  include non-volatile RAM (NVRAM), phase-change RAM (PC-RAM), magnetic RAM (MRAM), resistive RAM, spin torque transfer magneto-resistive RAM (STT-MRAM), and Intel Optane™ devices based on 3D XPoint™ memory. These and various combinations of multiple different types of NVM devices may also be used. For example, hard disk drives (HDDs) can be used in combination with or in place of SSDs or other types of NVM devices in the public cloud platforms  120 . 
     It is therefore to be appreciated that numerous different types of storage devices  130  can be used in public cloud platforms  120  in other embodiments. For example, a given public cloud platform  120  as the term is broadly used herein can include a combination of different types of storage devices, as in the case of a multi-tier storage system comprising a flash-based fast tier and a disk-based capacity tier. In such an embodiment, each of the fast tier and the capacity tier of the multi-tier storage system comprises a plurality of storage devices with different types of storage devices being used in different ones of the storage tiers. For example, the fast tier may comprise flash drives while the capacity tier comprises HDDs. The particular storage devices used in a given storage tier may be varied in other embodiments, and multiple distinct storage device types may be used within a single storage tier. The term “storage device” as used herein is intended to be broadly construed, so as to encompass, for example, SSDs, HDDs, flash drives, hybrid drives or other types of storage devices. 
     The term “storage system” as used herein is therefore intended to be broadly construed, and should not be viewed as being limited to particular storage system types, such as, for example, CAS systems, distributed storage systems, or storage systems based on flash memory or other types of NVM storage devices. A given storage system as the term is broadly used herein can comprise, for example, any type of system comprising multiple storage devices, such as network-attached storage (NAS), storage area networks (SANs), direct-attached storage (DAS) and distributed DAS, as well as combinations of these and other storage types, including software-defined storage. 
     The user devices  102  are configured to interact over the network  104  with one or more of the public cloud platforms  120 . Such interaction illustratively includes generating IO operations, such as write and read requests, and sending such requests over the network  104  for processing by one or more of the public cloud platforms  120 . In some embodiments, each of the user devices  102  comprises a driver configured to control delivery of IO operations from the host device to one or more of the public cloud platforms  120  over one or more paths through the network  104 . 
     The public cloud platforms  120  may further include one or more additional modules and other components typically found in conventional implementations of public cloud storage systems, although such additional modules and other components are omitted from the figure for clarity and simplicity of illustration. 
     The public cloud platforms  120  in the  FIG. 1  embodiment are assumed to be implemented using at least one processing platform, with each such processing platform comprising one or more processing devices, and each such processing device comprising a processor coupled to a memory. Such processing devices can illustratively include particular arrangements of compute, storage and network resources. As indicated previously, the user devices  102  (for example, when implemented as host devices) may be implemented in whole or in part on the same processing platform as the public cloud platforms  120  or on a separate processing platform. 
     The term “processing platform” as used herein is intended to be broadly construed so as to encompass, by way of illustration and without limitation, multiple sets of processing devices and associated storage systems that are configured to communicate over one or more networks. For example, distributed implementations of the system  100  are possible, in which certain components of the system reside in one data center in a first geographic location while other components of the system reside in one or more other data centers in one or more other geographic locations that are potentially remote from the first geographic location. Thus, it is possible in some implementations of the system  100  for the host devices  102  and the public cloud platforms  120  to reside in different data centers. Numerous other distributed implementations of the host devices and the public cloud platforms  120  are possible. 
     The network  104  is assumed to comprise a portion of a global computer network such as the Internet, although other types of networks can be part of the computer network  100 , including a wide area network (WAN), a local area network (LAN), a satellite network, a telephone or cable network, a cellular network, a wireless network such as a Wi-Fi or WiMAX network, or various portions or combinations of these and other types of networks. The computer network  100  in some embodiments therefore comprises combinations of multiple different types of networks, each comprising processing devices configured to communicate using internet protocol (IP) or other related communication protocols. 
     In some embodiments, the private cloud platform  105  can be implemented on the premises of a respective organization, such as part of a data center. For example, at least some of the sensitive data of an organization that is protected using the disclosed multi-tenant data protection techniques can be stored in a traditional data center that is not part of a public or private cloud. Likewise, one or more disclosed functions of the module  112  and/or the module  114  of the private cloud platform  105  can be implemented in a public cloud platform  120 , and/or by a server device. 
     The private cloud platform  105  can further comprise one or more input-output devices (not shown), which illustratively comprise keyboards, displays or other types of input-output devices in any combination. Such input-output devices can be used, for example, to support one or more user interfaces  116  to the private cloud platform  105 , as well as to support communication between the private cloud platform  105  and other related systems and devices not explicitly shown. 
     The user devices  102  and the private cloud platform  105  in the  FIG. 1  embodiment are assumed to be implemented using at least one processing device. Each such processing device generally comprises at least one processor and an associated memory, and implements one or more functional modules for controlling certain features of the private cloud platform  105 . 
     More particularly, user devices  102  and private cloud platform  105  in this embodiment each can comprise a processor coupled to a memory and a network interface. 
     The processor illustratively comprises a microprocessor, a microcontroller, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other type of processing circuitry, as well as portions or combinations of such circuitry elements. 
     The memory illustratively comprises random access memory (RAM), read-only memory (ROM) or other types of memory, in any combination. The memory and other memories disclosed herein may be viewed as examples of what are more generally referred to as “processor-readable storage media” storing executable computer program code or other types of software programs. 
     One or more embodiments include articles of manufacture, such as computer-readable storage media. Examples of an article of manufacture include, without limitation, a storage device such as a storage disk, a storage array or an integrated circuit containing memory, as well as a wide variety of other types of computer program products. The term “article of manufacture” as used herein should be understood to exclude transitory, propagating signals. These and other references to “disks” herein are intended to refer generally to storage devices, including SSDs, and should therefore not be viewed as limited in any way to spinning magnetic media. 
     A network interface may allow the user devices  102 , the private cloud platform  105 , and/or one or more of the public cloud platforms  120  to communicate over the network  104  with each other (as well as one or more other networked devices), and illustratively comprises one or more conventional transceivers. 
     It is to be understood that the particular set of elements shown in  FIG. 1  for multi-tenant data protection using tenant-based token validation and data encryption is presented by way of illustrative example only, and in other embodiments additional or alternative elements may be used. Thus, another embodiment includes additional or alternative systems, devices and other network entities, as well as different arrangements of modules and other components. 
     For example, while one or more embodiments of the disclosure are illustrated using multiple clouds environments for the storage of protected multi-tenant data using tenant-based token validation and tenant-based data encryption, any cloud environment may be employed to store the encrypted multi-tenant data. For example, in other embodiments, a given public cloud platform  120  may comprise storage devices  130 - 1  through  130 -N. In addition, one or more of public cloud platforms  120 - 1  through  120 -N may be implemented using one or more private cloud platforms  105 . Further, the disclosed techniques for multi-tenant data protection using tenant-based token validation and data encryption, as implemented in the example of  FIG. 1  by the private cloud platform  105  and/or one or more public cloud platforms  120 , could be implemented in other embodiments by a user device  102  and/or a traditional data center. Thus, the term “cloud environment,” as used herein, shall be broadly construed to encompass public clouds, private clouds, data centers, portions thereof and/or combinations thereof, as those terms are understood by a person of ordinary skill in the art. 
       FIG. 2A  is a flow diagram illustrating an exemplary implementation of a multi-tenant data storage process  200  that uses tenant-based token validation and data encryption, according to one embodiment. In the example of  FIG. 2A , each data record (e.g., a document or a row in results of a Structured Query Language (SQL) query) is encrypted using a tenant-specific encryption key, provided that the user is authorized to access (e.g., write) the data of the tenant associated with the data record, as discussed further below. 
     In step  202 , data  240  to be stored, as discussed further below in conjunction with  FIG. 2B , is obtained, as well as an associated access token  280 , as discussed further below in conjunction with  FIG. 2C . In step  204 , a loop is then entered for each data record in the obtained data  240  from step  202 . A test is performed in step  206  to determine if the tenant associated with the current data record is identified in the tenant property of the access token  280  (e.g., a tenant-based token validation). If it is determined in step  206  that the tenant associated with the current data record is not identified in the tenant property of the access token  280 , then program control proceeds to step  214 , discussed below. 
     If, however, it is determined in step  206  that the tenant associated with the current data record is identified in the tenant property of the access token  280 , then an encryption key of the tenant is obtained in step  208 . The data record is then encrypted in step  210  using the obtained encryption key (e.g., a tenant-based data encryption) and the encrypted data record is stored in step  212 . 
     A test is performed in step  214  to determine if there is an additional data record to process. If it is determined in step  214  that there is an additional data record to process, then program control returns back to step  206  to process the additional data record. Otherwise, program control ends in step  216 . 
       FIG. 2B  illustrates an exemplary data record set  240  to be stored using the multi-tenant data storage process  200  of  FIG. 2A , according to some embodiments of the disclosure. In the example of  FIG. 2B , each data record to be stored is identified by a record identifier and comprises a tenant identifier and a data value. 
       FIG. 2C  illustrates an exemplary access token  280  for use in a multi-tenant storage environment, according to one or more embodiments of the disclosure. In some embodiments, the exemplary access token  280  extends a JSON Web Token (JWT), for example, that is based on an open standard (RFC 7519) and uses a JSON (JavaScript Object Notation) object. 
     In one or more embodiments, the exemplary access token  280  of  FIG. 2C  comprises a user identifier, a user name, an administrator field and a tenant field. The administrator field can be used to indicate whether the respective user has administrative privileges. The tenant field can be used to indicate that the associated user is authorized to access (e.g., read and/or write) the data of any tenants identified in the tenant field (property) of the token  280 . In addition, in some embodiments, the tenant field may alternatively indicate that the associated user has limited access (e.g., read only or write only access) to the data of one or more tenants identified in the tenant field of the token  280 . 
     When the user associated with token  280  of  FIG. 2C  attempts to store the exemplary data records  240  of  FIG. 2B , data record  242  will be rejected in step  206 , since token  280  does not indicate that the user is authorized to access (e.g., read and/or write) the data of tenant  2 . 
       FIG. 3A  is a flow diagram illustrating an exemplary implementation of a multi-tenant data read process  300  that uses tenant-based token validation and data decryption, according to at least one embodiment. In the example of  FIG. 3A , each data record that satisfies a user-specified input parameter is decrypted using a tenant-specific decryption key and provided as part of the returned data, provided that the user is authorized to access (e.g., read) the data of the tenant associated with the respective data record according to the token of the user. 
     In step  302 , the multi-tenant data read process  300  receives (i) a request to access data from stored data records, as discussed further below in conjunction with  FIG. 3C , according to a user-specified input parameter, and (ii) an access token  340 , as discussed further below in conjunction with  FIG. 3B , associated with the requesting user. Exemplary requests to obtain data according to exemplary user-specified input parameters are discussed further below in conjunction with  FIGS. 3D and 3E . 
     In step  304 , data satisfying the user-specified input parameter is obtained, and then the obtained data is grouped by tenant in step  306 . In step  308 , a loop is then entered for each tenant in the obtained data from step  304 . A test is performed in step  310  to determine if the current tenant is identified in the tenant property of the access token  340 . 
     If it is determined in step  310  that the current tenant is not identified in the tenant property of the access token  340 , then program control proceeds to step  318 , discussed below. If, however, it is determined in step  310  that the current tenant is identified in the tenant property of the access token  340 , then the decryption key of the current tenant is obtained in step  312 . The obtained data for the current tenant is then decrypted in step  314  using the obtained decryption key of the current tenant. The decrypted obtained data for the current tenant is then added in step  316  to a return object. 
     A test is performed in step  318  to determine if there is an additional tenant to process. If it is determined in step  318  that there is an additional tenant to process, then program control returns to step  310  to process the additional tenant. Otherwise, the return object (as discussed further below in conjunction with  FIGS. 3D and 3E ) is provided in step  320 . 
       FIG. 3B  illustrates an access token  340  received from another exemplary user in a multi-tenant storage environment, according to one or more embodiments of the disclosure. In at least some embodiments, the exemplary access token  340  of  FIG. 3B  has similar fields as the exemplary access token  280  of  FIG. 2C . 
       FIG. 3C  illustrates an exemplary data record set  370  that has been stored in a multi-tenant storage environment, according to some embodiments. In at least some embodiments, the exemplary data record set  370  of  FIG. 3C  has similar fields as the exemplary data record set  240  of  FIG. 2B . 
       FIGS. 3D and 3E  illustrate exemplary data record sets  380 ,  390 , respectively, returned in response to particular read requests from the user associated with the token  340  of  FIG. 3B  from the stored data record set  370  of  FIG. 3C , according to some embodiments. In the example of  FIG. 3D , the user-specified input parameter for a read request comprises a location specific input parameter that requests all data having a data location of Israel. For example, a user-specified input parameter may specify “Return all records having a data location of Israel.” The data record  372  of  FIG. 3C  is not returned because the location of data record  372  does not satisfy the user-specified location parameter. In addition, data record  374  of  FIG. 3C  is not returned because the user is not authorized to access the data of tenant  343  in the token  340 . 
     In the example of  FIG. 3E , the user-specified input parameter for a read request comprises a tenant specific input parameter that requests all data having a tenant identifier of Tenant  341 . For example, a user-specified input parameter may specify “Return all records of tenant Tenant  341 .” The data record  373  of  FIG. 3C  is not returned because the tenant of data record  373  does not satisfy the user-specified tenant parameter. Likewise, data record  374  of  FIG. 3C  is also not returned because the tenant of data record  374  does not satisfy the user-specified tenant parameter. 
       FIG. 4  is a flow diagram illustrating an exemplary implementation of a multi-tenant data storage process  400  that uses tenant-based token validation and data encryption, according to at least some embodiments. In the example of  FIG. 4 , a data record to be stored and a token associated with the requesting user are obtained in step  402 . As discussed above, for example, in conjunction with  FIG. 2B , each data record comprises a tenant identifier identifying a tenant associated with the respective data record. In addition, as discussed above, for example, in conjunction with  FIG. 2C , the received token comprises a tenant field indicating that the associated user is authorized to access (e.g., read and/or write) the data of any tenants identified in the tenant field (property) of the token. 
     In step  404 , an encryption key of the tenant associated with the data record is obtained, and the data record is encrypted in step  406  using the obtained encryption key. Finally, the encrypted data record is stored in step  408 . 
     In at least some embodiments, an evaluation can also be performed of whether the tenant associated with the data record is identified in the received token. A given data record can be read by obtaining a decryption key of the tenant associated with the given data record and decrypting the given data record using the decryption key. In addition, a read operation may also evaluate, using the token, whether the user is authorized to access the data of the tenant associated with the given data record. The decrypted given data record can be appended to a return object in one or more embodiments. 
     The particular processing operations and other network functionality described in conjunction with the flow diagrams of  FIGS. 2A, 3A and 4  are presented by way of illustrative example only, and should not be construed as limiting the scope of the disclosure in any way. Alternative embodiments can use other types of processing operations for multi-tenant data protection using tenant-based token validation and data encryption. For example, the ordering of the process steps may be varied in other embodiments, or certain steps may be performed concurrently with one another rather than serially. In one aspect, the process can skip one or more of the actions. In other aspects, one or more of the actions are performed simultaneously. In some aspects, additional actions can be performed. 
     One or more embodiments of the disclosure provide improved methods, apparatus and computer program products for multi-tenant data protection using tenant-based token validation and data encryption. The foregoing applications and associated embodiments should be considered as illustrative only, and numerous other embodiments can be configured using the techniques disclosed herein, in a wide variety of different applications. 
     Among other benefits, the disclosed techniques for multi-tenant data protection using tenant-based token validation and data encryption waste the time of a potential attacker, without their knowledge, as an attacker is not aware of the inherent data protection. In addition, the disclosed techniques for multi-tenant data protection protect against data leakage and other security threats. 
     In one or more embodiments, the disclosed multi-tenant data protection techniques are resilient to data theft and protect “data at rest,” since each data record is encrypted with an encryption key that is specific to the associated tenant. Data isolation is also provided since an attacker can obtain the credentials of one tenant, but a request to obtain data for another tenant will be unsuccessful due to the tenant-based token validation (required verification per tenant, for example in step  206  of  FIG. 2A , prevents the attacker from seeing the data of other tenants), as well as the tenant-based data encryption. In addition, the disclosed multi-tenant data protection techniques protect “data in transit,” since even if an attacker can read the data (for example, in transit from a database (e.g., by the vulnerability of SSL)), the data is encrypted using the tenant-based data encryption. The encrypted data is useless for the attacker until the encrypted data is decrypted using the tenant-based decryption. 
     It should also be understood that the disclosed multi-tenant data protection techniques, as described herein, can be implemented at least in part in the form of one or more software programs stored in memory and executed by a processor of a processing device such as a computer. As mentioned previously, a memory or other storage device having such program code embodied therein is an example of what is more generally referred to herein as a “computer program product.” 
     The disclosed techniques for multi-tenant data protection may be implemented using one or more processing platforms. One or more of the processing modules or other components may therefore each run on a computer, storage device or other processing platform element. A given such element may be viewed as an example of what is more generally referred to herein as a “processing device.” 
     As noted above, illustrative embodiments disclosed herein can provide a number of significant advantages relative to conventional arrangements. It is to be appreciated that the particular advantages described above and elsewhere herein are associated with particular illustrative embodiments and need not be present in other embodiments. Also, the particular types of information processing system features and functionality as illustrated and described herein are exemplary only, and numerous other arrangements may be used in other embodiments. 
     In these and other embodiments, compute services can be offered to cloud infrastructure tenants or other system users as a PaaS offering, although numerous alternative arrangements are possible. 
     Some illustrative embodiments of a processing platform that may be used to implement at least a portion of an information processing system comprise cloud infrastructure including virtual machines implemented using a hypervisor that runs on physical infrastructure. The cloud infrastructure further comprises sets of applications running on respective ones of the virtual machines under the control of the hypervisor. It is also possible to use multiple hypervisors each providing a set of virtual machines using at least one underlying physical machine. Different sets of virtual machines provided by one or more hypervisors may be utilized in configuring multiple instances of various components of the system. 
     These and other types of cloud infrastructure can be used to provide what is also referred to herein as a multi-tenant environment. One or more system components such as a cloud-based multi-tenant data protection engine, or portions thereof, are illustratively implemented for use by tenants of such a multi-tenant environment. 
     Cloud infrastructure as disclosed herein can include cloud-based systems such as AWS, GCP and Microsoft Azure. Virtual machines provided in such systems can be used to implement at least portions of a cloud-based multi-tenant data protection platform in illustrative embodiments. The cloud-based systems can include object stores such as Amazon S3, GCP Cloud Storage, and Microsoft Azure Blob Storage. 
     In some embodiments, the cloud infrastructure additionally or alternatively comprises a plurality of containers implemented using container host devices. For example, a given container of cloud infrastructure illustratively comprises a Docker container or other type of Linux Container (LXC). The containers may run on virtual machines in a multi-tenant environment, although other arrangements are possible. The containers may be utilized to implement a variety of different types of functionality within the storage devices. For example, containers can be used to implement respective processing devices providing compute services of a cloud-based system. Again, containers may be used in combination with other virtualization infrastructure such as virtual machines implemented using a hypervisor. 
     Illustrative embodiments of processing platforms will now be described in greater detail with reference to  FIGS. 5 and 6 . These platforms may also be used to implement at least portions of other information processing systems in other embodiments. 
       FIG. 5  shows an example processing platform comprising cloud infrastructure  500 . The cloud infrastructure  500  comprises a combination of physical and virtual processing resources that may be utilized to implement at least a portion of the information processing system  100 . The cloud infrastructure  500  comprises multiple virtual machines (VMs) and/or container sets  502 - 1 ,  502 - 2 , . . .  502 -L implemented using virtualization infrastructure  504 . The virtualization infrastructure  504  runs on physical infrastructure  505 , and illustratively comprises one or more hypervisors and/or operating system level virtualization infrastructure. The operating system level virtualization infrastructure illustratively comprises kernel control groups of a Linux operating system or other type of operating system. 
     The cloud infrastructure  500  further comprises sets of applications  510 - 1 ,  510 - 2 , . . .  510 -L running on respective ones of the VMs/container sets  502 - 1 ,  502 - 2 , . . .  502 -L under the control of the virtualization infrastructure  504 . The VMs/container sets  502  may comprise respective VMs, respective sets of one or more containers, or respective sets of one or more containers running in VMs. 
     In some implementations of the  FIG. 5  embodiment, the VMs/container sets  502  comprise respective VMs implemented using virtualization infrastructure  504  that comprises at least one hypervisor. Such implementations can provide multi-tenant data protection functionality of the type described above for one or more processes running on a given one of the VMs. For example, each of the VMs can implement multi-tenant data protection control logic and associated token verification functionality for one or more processes running on that particular VM. 
     An example of a hypervisor platform that may be used to implement a hypervisor within the virtualization infrastructure  504  is the VMware® vSphere® which may have an associated virtual infrastructure management system such as the VMware® vCenter™. The underlying physical machines may comprise one or more distributed processing platforms that include one or more storage systems. 
     In other implementations of the  FIG. 5  embodiment, the VMs/container sets  502  comprise respective containers implemented using virtualization infrastructure  504  that provides operating system level virtualization functionality, such as support for Docker containers running on bare metal hosts, or Docker containers running on VMs. The containers are illustratively implemented using respective kernel control groups of the operating system. Such implementations can provide multi-tenant data protection functionality of the type described above for one or more processes running on different ones of the containers. For example, a container host device supporting multiple containers of one or more container sets can implement one or more instances of multi-tenant data protection control logic and associated token verification functionality. 
     As is apparent from the above, one or more of the processing modules or other components of system  100  may each run on a computer, server, storage device or other processing platform element. A given such element may be viewed as an example of what is more generally referred to herein as a “processing device.” The cloud infrastructure  500  shown in  FIG. 5  may represent at least a portion of one processing platform. Another example of such a processing platform is processing platform  600  shown in  FIG. 6 . 
     The processing platform  600  in this embodiment comprises at least a portion of the given system and includes a plurality of processing devices, denoted  602 - 1 ,  602 - 2 ,  602 - 3 , . . .  602 -K, which communicate with one another over a network  604 . The network  604  may comprise any type of network, such as a WAN, a LAN, a satellite network, a telephone or cable network, a cellular network, a wireless network such as WiFi or WiMAX, or various portions or combinations of these and other types of networks. 
     The processing device  602 - 1  in the processing platform  600  comprises a processor  610  coupled to a memory  612 . The processor  610  may comprise a microprocessor, a microcontroller, an ASIC, an FPGA or other type of processing circuitry, as well as portions or combinations of such circuitry elements, and the memory  612 , which may be viewed as an example of a “processor-readable storage media” storing executable program code of one or more software programs. 
     Articles of manufacture comprising such processor-readable storage media are considered illustrative embodiments. A given such article of manufacture may comprise, for example, a storage array, a storage disk or an integrated circuit containing RAM, ROM or other electronic memory, or any of a wide variety of other types of computer program products. The term “article of manufacture” as used herein should be understood to exclude transitory, propagating signals. Numerous other types of computer program products comprising processor-readable storage media can be used. 
     Also included in the processing device  602 - 1  is network interface circuitry  614 , which is used to interface the processing device with the network  604  and other system components, and may comprise conventional transceivers. 
     The other processing devices  602  of the processing platform  600  are assumed to be configured in a manner similar to that shown for processing device  602 - 1  in the figure. 
     Again, the particular processing platform  600  shown in the figure is presented by way of example only, and the given system may include additional or alternative processing platforms, as well as numerous distinct processing platforms in any combination, with each such platform comprising one or more computers, storage devices or other processing devices. 
     Multiple elements of an information processing system may be collectively implemented on a common processing platform of the type shown in  FIG. 5 or 6 , or each such element may be implemented on a separate processing platform. 
     For example, other processing platforms used to implement illustrative embodiments can comprise different types of virtualization infrastructure, in place of or in addition to virtualization infrastructure comprising virtual machines. Such virtualization infrastructure illustratively includes container-based virtualization infrastructure configured to provide Docker containers or other types of LXCs. 
     As another example, portions of a given processing platform in some embodiments can comprise converged infrastructure such as VxRail™, VxRack™, VxBlock™, or Vblock® converged infrastructure commercially available from Dell Technologies. 
     It should therefore be understood that in other embodiments different arrangements of additional or alternative elements may be used. At least a subset of these elements may be collectively implemented on a common processing platform, or each such element may be implemented on a separate processing platform. 
     Also, numerous other arrangements of computers, servers, storage devices or other components are possible in the information processing system. Such components can communicate with other elements of the information processing system over any type of network or other communication media. 
     As indicated previously, components of an information processing system as disclosed herein can be implemented at least in part in the form of one or more software programs stored in memory and executed by a processor of a processing device. For example, at least portions of the functionality shown in one or more of the figures are illustratively implemented in the form of software running on one or more processing devices. 
     It should again be emphasized that the above-described embodiments are presented for purposes of illustration only. Many variations and other alternative embodiments may be used. For example, the disclosed techniques are applicable to a wide variety of other types of information processing systems. Also, the particular configurations of system and device elements and associated processing operations illustratively shown in the drawings can be varied in other embodiments. Moreover, the various assumptions made above in the course of describing the illustrative embodiments should also be viewed as exemplary rather than as requirements or limitations of the disclosure. Numerous other alternative embodiments within the scope of the appended claims will be readily apparent to those skilled in the art.