Mathod and system for metadata analysis and collection with privacy

Description of equivalent WO 2015123347 A1

METHOD AND SYSTEM FOR METADATA ANALYSIS AND COLLECTION WITH

PRIVACY

CROSS REFERENCES

[0001] This application claims the benefit of and priority to U.S. Provisional Application No.

61/938,685, filed on February 1 1 , 2014, entitled "Method and System for Metadata Analysis and

Collection with Privacy," the disclosure of which is hereby incorporated by reference in its entirety.

FIELD

[0002] The field of the present disclosure generally relates to secure network communications, more particularly, to a system and method for providing metadata analysis and collection with privacy.

BACKGROUND

[0003] Recent news reports exposed that government agencies (GA) perform the analysis of network communications to uncover terrorist and criminal organizations through the

communications and relationships among members of those organizations. Privacy advocates have raised concerns that the government agencies should not collect data from their citizens without probable cause, due process, and court authorization. They argue that private data collections suppress the freedom of speech, the freedom of the press, the freedom of religion, and other basic human rights through possible intimidation by government agencies.

[0004] Communications service providers (CSPs) may collect and retain communications data, billing records, and other business records that are related to user accounts in a normal course of providing services. Government agencies may ask the CSPs to preserve data to enable forensic analysis related to terrorist and criminal activities. [0005] While the public generally trusts the CSPs to protect personal data, the public do not want personal data to be turned over to government agencies. The government agencies attempt to build a graph of activities by target organizations but they are hindered if they have to perform the analysis of personal data that is resident across hundreds to thousands of CSPs. The analysis of data at such a large scale would require a query on every new user identity/number, resulting in a massive amount of queries and round-trip-delays for each query.

[0006] The scaling problem for queries involving a large number of CSPs is further complicated because multiple agencies in multiple nations may request such queries. The number of links and the number of queries required in addition to the CSP's scaling problem burdens both the government agencies and the CSPs.

[0007] One of the available solutions to the CSP's scaling problem is to use a trusted third party (TTP) system. Depending on laws or policies of a country, TTP functions may be implemented in a GA system. The TTP system provides added visibility, auditability, and oversight to the overall data analysis and collection processes. However, centralizing the data at the TTP moves the privacy concerns from the GA to the TTP. There remains a challenge to centralize data analysis and collection at the TTP while making the metadata invisible to the TTP for privacy issues.

SUMMARY

[0008] A system and method for metadata analysis and collection with privacy is disclosed. According to one embodiment, a trusted third party (TTP) system generates and transmits authorization keys to a government agency (GA) system and a communication service provider (CSP) system. The TTP system receives index records referencing records of subscribers from the CSP system and ingests the index records received from the CSP system. The TTP system receives a target index request from the GA system and sends a metadata record request to the CSP system based on the target index request. The CSP system sends metadata records to the TTP system, and the TTP system delivers the metadata records to the GA system. The metadata records are encrypted with encryption keys shared between the GA system and the CSP system such that the TTP system cannot decrypt the metadata records.

[0009] The above and other preferred features, including various novel details of implementation and combination of elements, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular methods and apparatuses are shown by way of illustration only and not as limitations. As will be understood by those skilled in the art, the principles and features explained herein may be employed in various and numerous embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The accompanying drawings, which are included as part of the present specification, illustrate the various embodiments of the present disclosed system and method and together with the general description given above and the detailed description of the preferred embodiment given below serve to explain and teach the principles of the present disclosure.

[0011] FIG. 1 illustrates a schematic diagram of an exemplary system for providing metadata analysis and collection with privacy, according to one embodiment;

[0012] FIG. 2 illustrates communication flows between a GA system and a TTP system, according to one embodiment;

[0013] FIG. 3 illustrates communication flows between a TTP system and a CSP system, according to one embodiment;

[0014] FIG. 4 illustrates communication flows within a TTP system, according to one embodiment;

[0015] FIG. 5 illustrates an exemplary process flowchart for metadata analysis and collection, according to one embodiment; and

[0016] FIG. 6 illustrates an exemplary computer architecture that may be used for the present system, according to one embodiment.

[0017] It should be noted that the figures are not necessarily drawn to scale and that elements of structures or functions are generally represented by reference numerals for illustrative purposes throughout the figures. It also should be noted that the figures are only intended to facilitate the description of the various embodiments described herein. The figures do not describe every aspect of the teachings described herein and do not limit the scope of the claims. DETAILED DESCRIPTION

[0018] A system and method for metadata analysis and collection with privacy is disclosed.

According to one embodiment, a trusted third party (TTP) system generates and transmits authorization keys to a government agency (GA) system and a communication service provider

(CSP) system. The TTP system receives index records referencing records of subscribers from the CSP system and ingests the index records received from the CSP system. The TTP system receives a target index request from the GA system and sends a metadata record request to the

CSP system based on the target index request. The CSP system sends metadata records to the

TTP system, and the TTP system delivers the metadata records to the GA system. The metadata records are encrypted with encryption keys shared between the GA system and the CSP system such that the TTP system cannot decrypt the metadata records.

[0019] In the following description, for purposes of clarity and conciseness of the description, not all of the numerous components shown in the schematic are described. The numerous components are shown in the drawings to provide a person of ordinary skill in the art a thorough enabling disclosure of the present system and method. The operation of many of the components would be understood to one skilled in the art.

[0020] Each of the additional features and teachings disclosed herein can be utilized separately or in conjunction with other features and teachings to provide a detachable frame for a mobile computer. Representative examples utilizing many of these additional features and teachings, both separately and in combination, are described in further detail with reference to the attached drawings. This detailed description is merely intended to teach a person of skill in the art further details for practicing preferred aspects of the present teachings and is not intended to limit the scope of the present disclosure. Therefore, combinations of features disclosed in the following detailed description may not be necessary to practice the teachings in the broadest sense and are instead taught merely to describe particularly representative examples of the present teachings.

[0021] Moreover, various features of the representative examples and the dependent claims may be combined in ways that are not specifically and explicitly enumerated in order to provide additional useful embodiments of the present teachings. In addition, it is expressly noted that all features disclosed in the description and/or the claims are intended to be disclosed separately and independently from each other for the purpose of original disclosure, as well as for the purpose of restricting the claimed subject matter independent of the compositions of the features in the embodiments and/or the claims. It is also expressly noted that all value ranges or indications of groups of entities disclose every possible intermediate value or intermediate entity for the purpose of original disclosure, as well as for the purpose of restricting the claimed subject matter. It is also expressly noted that the dimensions and the shapes of the components shown in the figures are designed to help understand how the present teachings are practiced but are not intended to limit the dimensions and the shapes shown in the examples.

[0022] The present disclosure addresses both the privacy and scaling issues associated with centralizing data at a trusted third party (TTP). The present disclosure minimizes metadata shared between communications service providers (CSPs) and government agencies (GAs) and preserves the confidentiality of the shared metadata.

[0023] FIG. 1 illustrates a schematic diagram of an exemplary system for providing metadata analysis and collection with privacy, according to one embodiment. The system 100 includes a government agency (GA) system 110, a communications service provider (CSP) system 120, and a trusted third party (TTP) system 130. The system 100 may include a plurality of GA systems, a plurality of CSP systems, and a plurality of TTP systems. The GA system 110, the CSP system 120, and the TTP system 130 shown in FIGS. 1-4 may represent one or more GA systems, CSP systems, and TTP systems, respectively. For example, the TTP systems may include different types of TTP instances, for example, telephony, email, Internet service provider (ISP), social media services, and other internet applications. Those instances might be operated by the same or different organizations or different parties.

[0024] According to one embodiment, a GA operates the GA system 1 10, a TTP operates the TTP system 130, and a CSP operates the CSP system 120. According to another embodiment, a GA operates the GA system 110 and the TTP system 130, while a CSP operates the CSP system 120 depending on laws or policies of a country. In this case, the GA operates the TTP instances implemented by the TTP system 130 and directly communicates with the CSP system 120. According to another embodiment, a GA operates the GA system 1 10, and a CSP operates the CSP system 120 and the TTP system 130. In this case, the CSP operates the TTP instances implemented by the TTP system 130 and directly communicates with the GA system 110.

According to yet another embodiment, a GA operates all of the GA system 110, the TTP system 130, and the CSP system 120.

[0025] More than one GA system 110 may request information from multiple CSP systems 120. The TTP system 130 provides a scalable and privacy supporting model and reduces the amount of transported data from the CSP system 120 to the requesting GA system 110. The system 100 as a whole performs metadata analysis and collection, and requests and responses are transported among the GA system 110, the CSP system 120, and the TTP system 130 via communications flows. The communications flows include transport crypto key 140, index record delivery 150, target index request 160, metadata record request 170, metadata record delivery 180a and 180b, and metadata record encryption key 190. The transport crypto key 140 herein may refer to any cryptological material including, but not limited to, credentials used to generate or share keys to secure communication flows and storage at any level. The cryptological material may provide security at link, IP, transport, or application levels as possible alternatives.

[0026] To establish secure communications for analyzing and collecting metadata records between the GA system 120 and the CSP system 130, the TTP system 130 generates transport crypto keys and sends the keys to the GA system 1 10 and the CSP system 120 via the transport crypto key 140. The transport crypto key 140 manages credentials and keys for metadata analysis and collection between the TTP system 130 and the GA system 1 10, and between the TTP system 130 and the CSP system 120. The transport crypto key 140 may be an asymmetric key or a symmetric key. The communication flows among the GA system 1 10, the CSP system 120, and the TTP system 130 are encrypted such that no other parties can gain access to private information of subscribers of the CSP system 120. Examples of data in the communication flow of the transport crypto key 140 include, but are not limited to, certificates and keys used to secure the subsequent communication flows 150- 180 such as layer 2 secure links, layer 3 Internet protocol security (IPsec) tunnels, TLS connection, or a message or an application payer payload encryption.

[0027] Separately from the transport crypto key 140, the CSP system 120 directly delivers the metadata record encryption key 190 to the GA system 1 10 without going through the TTP system 130. The metadata record encryption key 190 is established outside of the TTP system 130 and used for the GA system 1 10 to decrypt the encrypted metadata record received from the CSP system 120. The communication flows are opaque to the TTP system 130, and the TTP system 130 cannot decrypt the metadata records exchanged between the GA system 1 10 and the CSP system 120 because it does not have the metadata record encrypting key 190. [0028] The CSP system 120 delivers index records to the TTP system 130. The index records references records of subscribers of the CSP system 120. The index records of the CSP system 120 may be stored in a data center. According to one embodiment, the index record delivery 150 is a continuous process including a constant flow of data packets. The TTP system 130 stores the index records in a storage device. The GA system 1 10 sends a target index request 160 to the TTP system 130 for identifying activities and records of a target ID. In response to the target index request 160, the TTP system 130 performs analysis on the stored index records. After performing the analysis on the stored index records, the TTP system 130 sends a metadata record request 170 to the CSP system 120 that stores records of the target identity. In response, the CSP system 120 delivers a collection of minimized and encrypted metadata records to the TTP system 130 via the communication flow 180a, and the TTP system 130 passes the metadata records to the GA system 1 10 via the communication flow 180b.

[0029] According to one embodiment, the TTP system 130 acts on behalf of the GA system 110 to send the target index request 160 to other TTP system and aggregate a response back to the original GA system 110. In this case, the TTP system 130 acting as the GA system 110 may through crypto relationships need to re-encrypt before sending the response from other TTP systems to the GA system 110. Otherwise, the crypto relationship of the secondary TTP systems and the GA system 110 remains intact and the primary TTP system 130 simply aggregates the metadata delivery records 180. In another embodiment, the TTP functionality is operated by a selected central CSP 120 that issues the metadata record request 170 to other CSP systems and aggregates encrypted records for delivery to the GA system 110.

[0030] FIG. 2 illustrates communication flows between the GA system 1 10 and the TTP system 130, according to one embodiment. The GA system 110 includes various processes including an index transform process 21 1 , a metadata analysis process 212, an index request process 213, and a metadata collection process 214. The metadata analysis process 212 represents law

enforcement or intelligence investigative operations and forensics to determine a target ID 215 of a target (e.g., an individual, a group, an organization) of interest. The metadata analysis process 212 launches queries for the target ID 215 and consumes the query results received from the TTP system 130 via metadata record delivery flow 180b. The target ID 215 may be a telephone number, or a unique ID for the target of interest including, but not limited to, an IP address, an email address, an alias, a media access control (MAC) address, an international mobile subscriber identity (IMSI), an international mobile station equipment identity (IMEI), a credit card number, or a user name. The index transform process 21 1 receives the target ID 215 from the metadata analysis process 212 and encrypts the target ID 215 into a target index 216.

According to one embodiment, the target index 216 is created using a cryptographic one-way hash function generated with an initialization vector input. Therefore, the target ID value is hidden to the TTP system 130 by the cryptographic transform function. The index request process 213 receives the target index 216 from the index transform process 21 1 , packages a target index request 261 including the target index 216, and sends the target index request 261 to the TTP system 130 via the target index request 160.

[0031] The TTP system 130 delivers the metadata records 281 for the target index 216 to the metadata record collection process 214 via the metadata record delivery 180b. The metadata records 281 are encrypted by the CSP system 120 using the metadata record encryption key 190 as discussed in the example shown in FIG. 1. The metadata collection process 214 decrypts the encrypted metadata records 281 and sends the decrypted metadata records 217 to the metadata analysis process 212. The metadata collection process 214 may send the decrypted metadata records 217 to the metadata analysis process 212 in a batch or a stream of data packets.

[0032] FIG. 3 illustrates communication flows between the TTP system 130 and the CSP system 120, according to one embodiment. The CSP system 120 includes an index transform process 321 , a metadata record process 322, an index delivery process 323, a record retrieval process 324, and a metadata delivery process 325. The metadata record process 322 sends an index record request 326 to the index transform process 321. Using the index record request 326 received from the metadata record process 322, the index transform process 321 produces index records 327 and sends the index records 327 to the index delivery process 323. The index delivery process 323 delivers the index records 351 to the TTP system 130 via the index record delivery 150. The index records 351 include indexed records of the subscribers of the CSP system 120. The index records 351 may also include identifiers of multiple parties, for example, telephone numbers involved in a 2-way, 3 -way or a conference call. Each of such multiple party index records may have multiple indexes. In one embodiment, the index records 351 include a reference to a full record that can be later retrieved by the record retrieval process 324.

[0033] The records retrieval process 324 receives a metadata record request 170 including metadata record ID 371 from the TTP system 130 and pulls metadata records 328 from the metadata record process 322. For example, the metadata record request 170 may include several metadata record IDs 371. The record retrieval process 324 compiles the associated metadata records 328 as indicated by the metadata record IDs 371 and pushes the metadata record report 329 to the metadata delivery process 325. It is noted that the metadata record request 170 is a single request but can include a list of metadata record IDs 371. The metadata delivery process 325 encrypts the metadata records 329 to produce encrypted metadata records 381, and sends the metadata record 381 to the TTP system 130 via metadata record delivery 180a. The responses from the CSP system 120 for the metadata records may be broken into a series of messages or compiled in a single file. The delivery of the metadata records 381 from the CSP system 120 to the TTP system 130 may depend on the data transmission mechanism and the mutually agreed delivery process (e.g., a batch delivery, streamed delivery) between the TTP system 130 and the CSP system 120.

[0034] FIG. 4 illustrates communication flows within the TTP system 130, according to one embodiment. The TTP system 130 includes a crypto credential process 431 , an index ingest process 432, an index storage process 433, an index request graphing process 434, a record retrieval process 435, and a metadata delivery process 436. The crypto credential process 431 supports secure authenticated transmissions of credentials 441 to an authorized GA system 1 10 and the participating CSP system(s) 120. According to one embodiment, the crypto credential process 431 receives the credentials 441 from another certificate authority and sends the received credentials 441 to the GA system 1 10 and the CSP systems 120. The index ingest process 432 manages the receipt and organization of a sequence of index records 451 received from the CSP system 120. The index storage process 433 keeps the index record 437 for a predetermined retention time. The retention time may be proscribed by law and enforced by the government.

[0035] The index request graphing process 434 searches on a target index 450 received from the GA system 1 10 via target index request 160, compiles matching index records 438 to create metadata record list 439, and sends the metadata record list 439 to the record retrieval process 435. For example, the index request graphing process 434 creates a relational graph of the target(s) identified by the target index 450. The relational graph shows the relationships of a target with other targets that are within a predetermined number of hops. The index request graphing process 434 searches for the appearance of the target(s) in the index store 437 and pulls the matching records 438 from the index storage process 433. In the case of telephony TTP, the target index may be an originator (i. e. , caller), a destination (i.e. , callee) in a call, or may forward a call or play a role associated with the call. Other parties of an initial match hit are used as target indexes for a subsequent search. The index search may be performed in several iterations, and the number of iterations may vary depending on the national regulatory limits. For example, in a first iteration, the index request graphing process 434 pulls indexes of the target index 450. In a second iteration, the index request graphing process 434 pulls indexes of the target indexes that are one hop away from the target index 450. In subsequent iterations, more target indexes that are within a predetermined number of hops from the initial target index are pulled. The record retrieval process 435 may also indicate to the CSP system 120 to include as yet unindexed records associated with the target index 450 and associates, and sends a metadata record request 471 to the CSP system 120. Each of the CSP system 120 that includes the metadata records for the target ID receives the metadata record request 170. The metadata delivery process 436 receives and aggregates encrypted metadata records 481 from the CSP system 120. The aggregation of encrypted metadata records 481 may occur in a batch or in streams. The metadata delivery process 436 ensures that the encrypted metadata records 481 from the CSP system 120 are returned to the GA system 1 10. If a response received from a CSP system 120 is partial or incomplete, the metadata delivery process 436 may request that the record retrieval process 435 re-generates the metadata record request 170 and provide it to the CSP system 120.

[0036] The communication flows 140-180 further include a coordination flow between each GA system 1 10 and each CSP system 120 for delivering encryption keys to protect the metadata records that are tunneled through the TTP system 130. While it is possible to use a full-mesh model (i.e. , allowing each GA system 1 10 to communicate with each CSP system 120) for the delivery of metadata records 481 from a CSP system 120 to a GA system 1 10, the present system may adopt a hub and spoke model to allow the TTP system 130 to correlate and audit the correlation between target index requests, metadata record requests, and metadata record delivery. The delivery of metadata records 481 through the TTP system 130 provides assurance to auditors. It is noted that the present system minimizes the number of requests from the GA system 1 10 to the CSP system 120 by correlating and auditing the requests for and delivery of metadata using the TTP system 130. In a full-mesh model, each request by a GA system 1 10 may have to send a series of requests to multiple CSP systems 120 to be able to retrieve metadata records for a target of interest. The present system allows a GA system 1 10 to receive a single response from each CSP system 120 instead of exchanging multiple requests and responses.

[0037] FIG. 5 illustrates an exemplary process flowchart for metadata analysis and collection, according to one embodiment. The analysis and collection of requested metadata by a GA 120 is performed in four phases, security setup 501 , indexing of metadata 502, targeting by index 503, and metadata record delivery 504.

[0038] In the security setup phase 501 , credentials (e.g. , transport crypto key 140 shown in FIG. 1) are passed between the TTP system 130 and the GA system 1 10, and between the TTP system 130 and the CSP system 120 to establish credentials for secure delivery of data requests and responses. The transport crypto key 140 may represent a series of messages going back and forth to build and issue a certificate between two parties (e.g. , between the TTP system 130 and the GA system 1 10 and between the TTP system 130 and the CSP system 120). The established credentials allow for secure transport of legally authorized and retained data from the TTP system 130 to the requesting GA system 1 10. Separately, the GA system 1 10 and the CSP system 120 directly exchange credentials (e.g. , metadata record encryption keys 190 shown in FIG. 1) to secure delivery of metadata records end-to-end from the CSP system 120 to the GA system 1 10 without going through the TTP system 130. In one embodiment, public key infrastructure (PKI)-based certificates and mechanisms are used for authentication and authorization. For example, the present system uses symmetric keys and delivers a high volume of index and metadata records to the CSP system 120, the TTP system 130, and the GA system 1 10.

[0039] The CSP system 120 determines which business records to keep as metadata records (e.g., call detail records, emails, messages). Depending on the regulation and requests by the GAs 1 10, the CSP system 120 may add/delete/modify/retain metadata records. During the indexing of metadata phase 502, the CSP system 120 prepares the metadata records including records required by the GA system 1 10. For example, the CSP system 120 generates index records that contain hashes of the target IDs along with a globally unique record number (e.g., universally unique identifier (UUID)) and a timestamp to help manage the data retention duration. The CSP system 120 delivers the index records to the TTP system 130. It is noted that the delivery of the index records may not occur in a batch. Instead, the delivery of the index record may occur in a continuous process as business records are created in the CSP system 120. The TTP system 130 ingests a stream of index records received from multiple CSP systems 120 and stores the ingested stream of records in a high-volume data center for later search and retrieval.

[0040] During the targeting by index phase 503, the GA system 1 10 transforms requests for records related to target IDs into requests for target indexes using a hash function or indexing keys of the CSP system 120. Both the CSP system 120 and the GA system 1 10 perform the same transformation: hash using defined inputs (e.g., identity, initial vector), output index value, etc. From the index value, the TTP system 130 cannot discover a particular target identity, but can compare index values to determine whether they are the same or different. The GA system 1 10 delivers the target index to the TTP system 130 along with a request authorization document that is stored and managed by the GA system 1 10 for request handling and auditing purposes. Using the target index received from the GA system 1 10, the TTP system 130 performs searches for the target index across the index information provided by multiple CSP system 120. The TTP system 130 also performs additional searches on the hashed identity of associates (e.g., other parties found in the searches) found in the index records that contain the target-hashed identity. If permitted or requested by the GA system 1 10, the associates may be searched in an iterative process beyond the initial search. The TTP system 130 produces a list of UUIDs that map back to the metadata records of each CSP system 120. The TTP system 130 sends metadata record requests to the CSP system 120 that keeps the requested records for the UUIDs of interest. The CSP system 120 sends the metadata records to the GA system 1 10 along with the request authorization document.

[0041] During the metadata record delivery phase 504, the CSP system 120 encrypts the metadata records using symmetric keys shared with the requesting GA system 1 10 and delivers the metadata records encapsulated with the request authorization information to the TTP system 130. The TTP system 130 forwards the metadata record to the GA system 1 10. The TTP system 130 does not have visibility into the content of the metadata records because the TTP system 130 does not have the symmetric keys to decrypt the encrypted metadata records. However, the TTP system 130 can document the volume of metadata records that are needed to fulfill the request by the GA system 1 10. [0042] FIG. 6 illustrates an exemplary computer architecture that may be used for the present system, according to one embodiment. The exemplary computer architecture may be used for implementing one or more components described in the present disclosure including, but not limited to, the present content curation system. One embodiment of architecture 600 includes a system bus 601 for communicating information, and a processor 602 coupled to bus 601 for processing information. Architecture 600 further includes a random access memory (RAM) or other dynamic storage device 603 (referred to herein as main memory), coupled to bus 601 for storing information and instructions to be executed by processor 602. Main memory 603 also may be used for storing temporary variables or other intermediate information during execution of instructions by processor 602. Architecture 600 may also include a read only memory (ROM) and/or other static storage device 604 coupled to bus 601 for storing static information and instructions used by processor 602.

[0043] A data storage device 605 such as a magnetic disk or optical disc and its corresponding drive may also be coupled to architecture 600 for storing information and instructions.

Architecture 600 can also be coupled to a second I/O bus 606 via an I/O interface 607. A plurality of I/O devices may be coupled to I/O bus 606, including a display device 608, an input device (e.g., an alphanumeric input device 609 and/or a cursor control device 610).

[0044] The communication device 61 1 allows for access to other computers (e.g., servers or clients) via a network. The communication device 61 1 may include one or more modems, network interface cards, wireless network interfaces or other interface devices, such as those used for coupling to Ethernet, token ring, or other types of networks.

[0045] While some specific embodiments of the present disclosure have been shown, the present disclosure should not be interpreted to limit the scope of the present disclosure to these embodiments. For example, most functions performed by electronic hardware components may be duplicated by software emulation. Thus, a software program written to accomplish those same functions may emulate the functionality of the hardware components in input-output circuitry. The present disclosure is to be understood as not limited by the specific embodiments described herein, but only by scope of the appended claims.

[0046] Embodiments as described herein have significant advantages over previously developed implementations. As will be apparent to one of ordinary skill in the art, other similar apparatus arrangements are possible within the general scope. The embodiments described above are intended to be exemplary rather than limiting, and the bounds should be determined from the claims.