# Patent

## Title
Method and system for secure data collection and distribution

## Abstract

A data provider generates a data encryption key and an identifier, uses the data encryption key to encrypt data, sends the encrypted data and the identifier to a data requestor, and sends the data encryption key and the identifier to a crypto information server. The data requestor sends the identifier to the crypto information server to request the encryption key. The crypto information server authenticates the data requestor and, contingent on that authentication, sends the data encryption key to the data requestor. If a plurality of data instances are captured, then for each instance, a respective data encryption key and identifier are generated.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation application of U.S. patent application Ser. No. 11/519,971, filed Sep. 13, 2006, entitled “METHOD AND SYSTEM FOR SECURE DATA COLLECTION AND DISTRIBUTION”, which is incorporated in its entirety herein by reference.


FIELD AND BACKGROUND OF THE INVENTION
The present invention relates to a method and system for collecting data at a source and distributing the data to one or more destinations and, more particularly, to such a method and system in which the data are protected from eavesdropping and from unauthorized changes from when the data leave the source until the data arrive at their ultimate destination(s).
The efficient storage and retrieval of multi-channel data communications, and especially of voice data, are critically important in many modern business and government applications. For example, financial institutions record instructions from clients as a protection against fraud and as evidence in legal proceedings about the content of telephone conversations; public safety agencies record emergency calls for event reconstruction and future investigations; commercial entities monitor transactions over the phone to evaluate salespersons' efficiency, to ensure customer satisfaction and to develop training programs.
Data logging and retrieval systems for capturing, recording and retrieving data transmitted over multiple communication lines are known in the art. See for example Henits, U.S. Pat. No. 6,775,372, which patent is incorporated by reference for all purposes as if fully set forth herein, and the references cited therein. FIG. 1 is a high-level schematic block diagram of an exemplary prior art system 10 for capturing, storing and retrieving telephone conversations. System 10 is based on a Local Area Network (LAN) 12 that uses the IP protocol to transfer digital data, borne by IP packets, among the other components of system 10. System 10 includes several loggers 14, as described for example in the Henits patent, for capturing digital data that represent telephone conversations. Digital records of the telephone conversations are stored in an archive 18. A controller 16 manages LAN 12.
LAN 12 is connected to the outside world, specifically to a Wide Area Network (WAN) 22 such as the worldwide Internet, by a Web server 20. User terminals 24, represented as personal computers, also are connected to WAN 22. A user of a terminal 24 uses a standard Web browser to access data stored in archive 18 via Web server 20.
System 10 is vulnerable to eavesdropping. Even if, as is usually the case, data captured by loggers 14 is encrypted and is stored in an encrypted form in archive 14, Web server 20 typically decrypts data requested by a user of a terminal 24 before exporting the data to WAN 22. There are many ways in which eavesdroppers can intercept the data on WAN 22, especially if WAN 22 is the worldwide Internet.
System 10 also is vulnerable to unauthorized modification of the data. This is true even if access to data in archive 18 were to be limited to terminals connected to LAN 12. For example, if archive 14 is responsible for encryption, data can be tampered with in transit from loggers 14 to archive 18.
There is thus a widely recognized need for, and it would be highly advantageous to have, a data collection and distribution system in which the data are continuously protected from eavesdropping and unauthorized modification, from when the data leave their original source until the data arrive at their ultimate destination.
SUMMARY OF THE INVENTION
The present invention defends data against eavesdropping by encrypting the data as soon as the data are collected or generated and then keeping the data encrypted at all times until the data actually are displayed to an authorized user.
According to the present invention there is provided a method of distributing data, including the steps of (a) encrypting the data, using a data encryption key, thereby providing encrypted data; (b) requesting the data, by a data requestor; (c) in response to the request, sending the encrypted data to the data requestor; (d) authenticating the data requestor, by a crypto information server; and (e) contingent on the authenticating, sending the data encryption key to the data requestor, by the crypto information server.
According to the present invention there is provided a system for secure distribution of data, including: (a) a data requestor; (b) a data provider operative: (i) to encrypt the data using a data encryption key, thereby providing encrypted data, and (ii) to send the encrypted data to the data requestor; and (c) a crypto information server operative: (i) to authenticate the data requestor, and (ii) contingent on the authentication, to send the data encryption key to the data requestor.
According to the present invention there is provided a method of collecting and distributing a plurality of instances of data, including the steps of: (a) for each instance: (i) generating a respective data encryption key, and (ii) encrypting the each instance, using the respective data encryption key, thereby providing respective encrypted data; (b) requesting at least a portion of one of the instances, by a data requestor; and (c) in response to the request, sending a corresponding portion of the respective encrypted data of the one instance to the data requestor.
According to the present invention there is provided a system for secure collection and distribution of a plurality of instances of data, including: (a) a set, of at least one data provider, operative: (i) to capture the instances, and (ii) for each instance: (A) to generate a respective data encryption key, and (B) to encrypt the each instance, using the respective data encryption key, thereby providing respective encrypted data; (b) a data requestor operative: (i) to request at least a portion of one of the instances; and (c) an archive operative: (i) to store the encrypted data; and (ii) in response to the request of the at least portion of the one instance by the data requestor: to send a corresponding portion of the respective encrypted data of the one instance to the data requestor.
The first method of the present invention is a method of distributing data such as voice data, voice over IP (VoIP) data, video data and screen data, among others. According to the basic embodiment of the first method, the data are encrypted, using a data encryption key, to provide encrypted data. When a data requestor requests the data, the encrypted data are sent to the data requestor. A crypto information server authenticates the data requestor. Contingent on the authenticating, i.e., if the crypto information server determines that the data requestor is authorized to receive the data, the crypto information server sends the data encryption key to the data requestor. Preferably, the data encryption key is a symmetric key, to enable the data requestor to decrypt the encrypted data. In the preferred embodiments below, user terminals 34 and 112 are the data requestors.
Preferably, the data encryption key is sent to the data requestor in encrypted form.
Preferably, the data requestor requests the data encryption key, and the authentication of the data requestor is in response to that request.
Preferably, the method includes generating the data encryption key and associating the data encryption key with a respective identifier. Most preferably, the data encryption keys are generated according to a predefined key granularity.
More preferably, the identifier is sent to the data requestor along with the encrypted data; and the data requestor sends the identifier to the crypto information server to request the data encryption key. The authentication of the data requestor is in response to receipt of the identifier from the data requestor by the crypto information server.
Also more preferably, the crypto information server stores the data encryption key and the identifier in a database. Most preferably, the data encryption key is stored in the database in encrypted form, to prevent unauthorized access of the data encryption key.
Preferably, the data are encrypted by a data provider, and the encrypted data also are stored in an archive that is separate from the data provider. When the data requestor requests the data, the encrypted data are sent to the data requestor from the archive. In the preferred embodiments below, loggers 32 are the data providers.
Preferably, a message authentication code is attached to the data prior to encrypting the data, so that the message authentication code becomes part of the data and is encrypted along with the data. The attaching of the message authentication code to the data may be, for example, by appending the message authentication code to the data, by prepending the message authentication code to the data or by inserting the message authentication code in the data. Contingent on the authenticating, the crypto information server sends a message authentication code key of the message authentication code to the data requestor.
More preferably, the method includes the steps of generating the data encryption key and the message authentication code key and associating the data encryption key and the message authentication code key with a common respective identifier. The identifier is sent to the data requestor along with the encrypted data; and the data requestor sends the identifier to the crypto information server to request the data encryption key and the message authentication code key. The authentication of the data requestor is in response to receipt of the identifier from the data requestor by the crypto information server. Most preferably, the data encryption key and the message authentication code key are generated according to a predefined key granularity.
Also more preferably, the crypto information server stores the data encryption key, the message authentication code key and the identifier in a database. Most preferably, the data encryption key and the message authentication code key are stored in the database in encrypted form, to prevent unauthorized access of the data encryption key and the message authentication code key.
A first basic system of the present invention, for secure distribution of data, includes a data requestor, a data provider and a crypto information server. The data provider encrypts the data using a data encryption key, thereby providing encrypted data, and sends the encrypted data to the data requestor. The crypto information server authenticates the data requestor. Contingent on that authentication, i.e., if the crypto information server determines that the data requestor is authorized to receive the data, the crypto information server sends the data encryption key to the data requestor. Preferably, the crypto information server sends the data encryption key to the data requestor in encrypted form.
Preferably, the data provider also generates the data encryption key and associates the data encryption key with a respective identifier. Most preferably, the data provider generates the data encryption key according to a predefined key granularity. More preferably, the data provider also sends the identifier to the data requestor along with the encrypted data and also sends the data encryption key to the crypto information server along with the identifier. The data requestor requests the data encryption key from the crypto information server by sending the identifier to the crypto information server. The authentication of the data requestor by the crypto information server then is in response to receipt of the identifier from the data requestor by the crypto information server.
Most preferably, both the data provider and the data requestor include respective instances of a crypto information client that is operative to generate the data encryption key and its respective identifier, to send the data encryption key and its identifier to the crypto information server, and to request the data encryption key from the crypto information server by sending the identifier to the crypto information server.
Even more preferably, the system also includes a database wherein the crypto information server stores the data encryption key and the identifier. Most preferably, the data encryption key is stored in the database in encrypted form.
Preferably, the system also includes an archive, separate from the data provider, for storing the encrypted data. The sending of the encrypted data from the data provider to the data requestor may be either direct or via the archive: most preferably, the archive is operative to send the encrypted data to the data requestor.
Preferably, the data provider also attaches a message authentication code to the data prior to encrypting the data, and, contingent on the authenticating, the crypto information server sends a message authentication code key to the data requestor.
More preferably, the data provider also generates the data encryption key and the message authentication code key, and associates the data encryption key and the message authentication code key with a common respective identifier. Even more preferably, the data provider also sends the identifier to the data requestor along with the encrypted data and also sends the data encryption key and the message authentication code key to the crypto information server along with the identifier. The data requestor requests the data encryption key and the message authentication code key from the crypto information server by sending the identifier to the crypto information server. The authentication of the data requestor by the crypto information server then is in response to receipt of the identifier from the data requestor by the crypto information server. Most preferably, the data provider generates the data encryption key and the message authentication code key according to a predefined key granularity.
Most preferably, both the data provider and the data requestor include respective instances of a crypto information client that is operative to generate the data encryption key, the message authentication code key and their respective common identifier, to send the data encryption key, the message authentication code key and their identifier to the crypto information server, and to request the data encryption key and the message authentication code key from the crypto information server by sending the identifier to the crypto information server.
Even more preferably, the system also includes a database wherein the crypto information server stores the data encryption key, the message authentication code key and the identifier. Most preferably, the data encryption key and the message authentication code key are stored in the database in encrypted form.
A second method of the present invention is a method of collecting and distributing a plurality of instances of data What constitutes an “instance” of data is implementation dependent. For example, in the first preferred embodiment discussed below, the data instances are files of audio data, and in the second preferred embodiment discussed below, the data instances are all the data captured in different external channels and all the data captured as a result of different initializations of screen agents 118. According to the basic embodiment of the second method, for each data instance, a corresponding respective data encryption key is generated and the data instance is encrypted using that data encryption key, thereby providing respective encrypted data. When a data requestor requests at least a portion of one of the data instances, a corresponding portion of the requested data instance's respective encrypted data is sent to the data requestor.
Preferably, the requested data instance includes voice data, VoIP data, video data and/or screen capture data.
Preferably, the data encryption keys are symmetric keys, to enable the data requestor to decrypt the encrypted data.
Preferably, the data encryption keys are generated according to a predefined key granularity.
Preferably, each data instance is captured by a respective data provider that then generates the respective data encryption key and uses that data encryption key to encrypt the data instance.
Most preferably, the respective encrypted data of each data instance are stored in an archive separate from the data provider that captured the data instance. Encrypted data are sent to the data requestor from the archive rather than from the data provider that captured the corresponding data instance.
Preferably, the data requestor is authenticated by a crypto information server. Contingent on the authenticating, i.e., if the crypto information server determines that the data requestor is authorized to receive the data, the crypto information server sends the respective data encryption key of the requested data instance portion to the data requestor, most preferably in encrypted form. More preferably, the authenticating is in response to the data requestor requesting the respective data encryption key of the requested data instance portion. Most preferably, each data encryption key is associated with a respective identifier that is sent to the data requestor along with the requested data instance portion, and the data requestor requests the respective data encryption key of the requested data instance portion by sending the associated identifier to the crypto information server. Also even more preferably, the crypto information server stores the data encryption keys and the identifiers in a database, most preferably in encrypted form.
Preferably, a respective message authentication code is attached to each data instance prior to encrypting the data instance, so that the message authentication code becomes part of the data instance and is encrypted along with the data instance. More preferably, a respective message authentication code key is generated and is used to generate the respective message authentication code. Most preferably, the message authentication code keys are generated according to a predefined key granularity. The attaching of the message authentication code to the data instance may be, for example, by appending the message authentication code to the data instance, by prepending the message authentication code to the data instance or by inserting the message authentication code in the data instance. The data requestor is authenticated by a crypto information server. Contingent on the authenticating, i.e., if the crypto information server determines that the data requestor is authorized to receive the data, the crypto information server sends the respective data encryption key of the requested data instance portion, along with a message authentication code key of the requested data instance portion, to the data requestor, most preferably in encrypted form. More preferably, the authenticating is in response to the data requestor requesting the respective data encryption key and the respective message authentication code key of the requested data instance portion. Most preferably, each data-encryption-key-message-authentication-code-key pair is associated with a respective identifier that is sent to the data requestor along with the requested data instance portion, and the data requestor requests the respective data encryption key and the respective message authentication code key of the requested data instance portion by sending the associated identifier to the crypto information server. Also even more preferably, the crypto information server stores the data encryption keys, the message authentication code keys and the identifiers in a database, most preferably in encrypted form.
A second basic system of the present invention, for secure collection and distribution of a plurality of instances of data, includes a set of one or more data providers, a data requestor and an archive. The set of data providers capturers the data instances and, for each captured data instance, generates a respective data encryption key and uses that data encryption key to encrypt the data instance, thereby providing respective encrypted data. The data requestor requests at least a portion of one of the data instances. The encrypted data are stored in the archive. In response to the request for the data instance portion, the archive sends the data requestor a corresponding portion of the respective encrypted data of the requested data instance portion.
Although the set of data providers could serve to archive their own encrypted data, especially in an embodiment with only one data provider, it is preferable that the archive be separate from the set of data providers.
Preferably, the set of data providers generates the data encryption keys according to a predefined key granularity.
Preferably, the system also includes a crypto information server that authenticates the data requestor and that, contingent on the authentication (i.e., if the crypto information server determines that the data requestor is authorized to receive the data), sends the respective data encryption key of the requested data instance portion to the data requestor, most preferably in encrypted form.
More preferably, the data requestor also requests the respective data encryption key of the requested data instance portion from the crypto information server, and the authenticating is in response to that request. Even more preferably, the set of data providers associates each data encryption key with a respective identifier, and the archive, in response to the request of the data instance portion by the data requestor, sends the respective identifier of the requested data instance portion to the data requestor along with the requested data instance portion. The data requestor then requests the respective data encryption key of the requested data instance portion from the crypto information server by sending the identifier of the requested data instance portion to the crypto information server.
Most preferably, each data provider, as well as the data requestor, includes a respective instance of a crypto information client that is operative to generate the data encryption keys and the identifiers, to send the data encryption keys and the identifiers to the crypto information server, and to request the data encryption keys from the crypto information server by steps including, for each requested data encryption key, sending the identifier of the requested data encryption key to the crypto information server.
More preferably still, the system also includes a database wherein the crypto information server stores the data encryption keys and the identifiers, most preferably in encrypted form.
Preferably, the set of data providers also generates a respective message authentication code key for each data instance, uses that message authentication code key to generate a respective message authentication code, and attaches the respective message authentication code key thus generated to the data instance prior to encrypting the data instance. Most preferably, the set of data providers generates the message authentication code keys according to a predefined key granularity. The system also includes a crypto information server that authenticates the data requestor and that, contingent on that authentication, sends the respective data encryption key and the respective message authentication code key of the requested data instance portion to the data requestor, most preferably in encrypted form.
Even more preferably, the set of data providers associates each data-encryption-key-message-authentication-code-key pair with a respective identifier, and the archive, in response to the request of the data instance portion by the data requestor, sends the respective identifier of the requested data instance portion to the data requestor along with the requested data instance portion. The data requestor then requests the respective data encryption key and the respective message authentication code key of the requested data instance portion from the crypto information server by sending the identifier of the requested data instance portion to the crypto information server.
Most preferably, each data provider, as well as the data requestor, includes a respective instance of a crypto information client that is operative to generate the data encryption keys, the message authentication code keys and the identifiers, to send the data encryption keys, the message authentication code keys and the identifiers to the crypto information server, and to request the data encryption keys and the message authentication code keys from the crypto information server by steps including, for each requested data-encryption-key-message-authentication-code-key pair, sending the identifier of the requested data-encryption-key-message-authentication-code-key pair to the crypto information server.
More preferably still, the system also includes a database wherein the crypto information server stores the data encryption keys, the message authentication code keys and the identifiers, most preferably in encrypted form.
Blair et al., in US Patent Application Publication No. 2006/0123106, teach a wiretapping device that is intended to be used by law enforcement officials to secretly record conversations legally even before such recording has been authorized by a judge. The device encrypts the conversations immediately upon intercept, using a password that is available to the law enforcement officials only from the judge, and stores the encrypted conversations. Without receiving the password from the judge, the recorded conversations are unintelligible to the law enforcement officials. Unlike the present invention, the device of Blair et al. lacks mandatory end-to-end encryption: having obtained the password, the law enforcement officials are free to decrypt the conversations in-place.
Coordinated Systems, Inc. of East Hartford Conn., USA, offers a data logging and retrieval system called Virtual Observer that is similar to the logging system of the present system, insofar as Virtual Observer encrypts the data immediately on capture and conditions playback of archived data on authentication of the party requesting the playback. However, as far as the present inventors are aware, Virtual Observer sends unencrypted data to authenticated requesting parties and so lacks the end-to-end authentication of the present invention.



BRIEF DESCRIPTION OF THE DRAWINGS
The invention is herein described, by way of example only, with reference to the accompanying drawings, wherein:
FIG. 1 is a high-level schematic block diagram of a prior art system for capturing, storing and retrieving telephone conversations;
FIG. 2 is a high-level schematic block diagram of the system of FIG. 1 as modified according to the present invention;
FIG. 3 is a high-level schematic block diagram of a logger of the system of FIG. 2;
FIG. 4 is a high-level schematic block diagram of a user terminal of the system of FIG. 2;
FIG. 5 illustrates the data flow in the system of FIG. 2;
FIG. 6 is a high-level schematic block diagram of a second system of the present invention;
FIGS. 7A through 7T, 8A-1 through 8A-28 and 9A through 9N are vendor descriptions of the prior art NICE Perform® system of which the preferred systems of the present invention described herein are improvements.



DESCRIPTION OF THE PREFERRED EMBODIMENTS
The principles and operation of a data collection and distribution system according to the present invention may be better understood with reference to the drawings and the accompanying description.
Referring again to the drawings, FIG. 2 is a high-level schematic block diagram of a first system 30 of the present invention. Specifically, system 30 is system 10 of FIG. 1 modified according to the principles of the present invention. System 30 inherits LAN 12, archive 18, Web server 20 and WAN 22 from system 10 substantially unchanged. The new components of system 30 include modified loggers 32, modified user terminals 34, a modified controller 36 and a key database 38.
FIG. 3 is a high-level schematic block diagram of a logger 32 of the system 30, for logging multichannel audio input. Logger 32 includes an input interface 44 to the audio input, a digital signal processor (DSP) 48, a controller 50, a non-volatile memory 52 and an output interface 54 to LAN 12. Depending on how interface 44 is configured, the audio input could be, for example, analog input, digital extension input, E1/T1 trunk input or VoIP input. Controller 50 is responsible for overall operation of logger 32. One of the features of controller 50 that is relevant to the present invention is that controller 50, with the help of an instance 56 of a crypto information client, as described below, attaches a message authentication code (MAC) to the compressed data that controller 50 receives from DSP 48 and then encrypts the compressed data together with the MAC. Controller 50 stores the encrypted data in non-volatile memory 52 and retrieves the stored encrypted data from non-volatile memory 52. Controller 50 also exchanges data with LAN 12 via interface 54.
FIG. 4 is a high-level schematic block diagram of a user terminal 34 of the present invention. Terminal 34 includes an interface 58 to LAN 12, a controller 60, a set of user output devices represented by a display block 62 and a set of user input devices represented by an input block 64. The user input devices represented by input block 64 include standard input devices such as a keyboard and a mouse. The user output devices represented by display block 62 include standard output devices such as a video display screen, a speaker and a printer. Controller 60 is responsible for overall operation of terminal 34. A user of terminal 34 uses input devices 64 to request data for display from web server 20. The data are received via interface 58 and are displayed at one or more of output devices 62. The data are exported in encrypted fault, as described below; and one of the features of controller 60 that is relevant to the present invention is that controller 60, with the help of an instance 66 of a crypto information client, as described below, decrypts the data for display and verifies that the data have not been altered subsequent to their encryption by their source logger 32. Note that in the present context, “displaying” data means presenting the data to a user in a perceptible form: visually at a display screen, audibly via a speaker, etc.
The crypto information client of the present invention has several functions. One of these functions is the generation of the MAC keys that are used by controller 50 to generate MACs and of the data encryption keys that are used by controller 50 to encrypt data. Any conventional real-time symmetric encryption algorithm may be used, but the preferred algorithm is the AES algorithm. Preferably, each MAC key is 128 bits long and each data encryption key is 256 bits long. The data encryption keys and the MAC keys are generated according to a predefined key granularity, for example, per telephone conversation or periodically (e.g. daily or monthly), rather than according to a master key. For each file that controller 50 needs to encrypt, instance 56 of the crypto information client generates an associated MAC key, an associated symmetric data encryption key and a corresponding Global Unique Identifier (GUID). Periodically, for example at the end of a telephone conversation, controller 50 sends the accumulated files and the corresponding GUIDs from non-volatile memory 52 to archive 18 via LAN 12. At the same time, controller 50 sends the associated MAC keys, the associated data encryption keys and the corresponding GUIDs to controller 36 via LAN 12. Crypto information server 40 of controller 36 encrypts the MAC keys and the data encryption keys for storage, along with the corresponding GUIDs, in database 38.
The data that terminal 34 receives from Web server 20 are encrypted and so are useless unless terminal 34 can decrypt the data. Terminal 34 also needs to verify the authenticity of the data, to make sure that the data have not been modified subsequent to their encryption by logger 32. Therefore, another function of the crypto information client of the present invention is fetching MAC keys and data encryption keys from database 38. Terminal 34 receives data files from Web server 20 along with the corresponding GUIDs. For each data file that terminal 34 receives from Web server 20, instance 56 of the crypto information client sends the corresponding GUID to controller 36 with a request for the associated MAC key and the associated data encryption key. Crypto information server 40 negotiates with instance 56 of the crypto information client to authorize the sending of the MAC key and the data encryption key to terminal 34. If terminal 34 is authorized to receive the MAC key and the data encryption key, crypto information server 40 fetches the MAC key and the data encryption key from database 38 according to the GUID received from terminal 34, decrypts the MAC key and the data encryption key and sends the MAC key and the data encryption key to the requesting terminal 34.
Authentication methods suitable for use by crypto information server 40 and instance 56 of the crypto information client are well-known in the art and need not be elaborated herein. For example, in an Active Directory® environment, a protocol such as Kerberos or Integrated Windows Authentication (IWA) is used. In a non-Active-Directory environment, crypto information server 40 and instance 56 of the crypto information client authenticate each other by exchanging public key certificates. In either case, if the authentication is successful, crypto information server 40 sends the requested keys to terminal 34 in encrypted form, albeit encrypted differently than how the keys are stored in database 38. For example, in a non-Active-Directory environment, crypto information server 40 uses a public key algorithm to encrypt the requested keys. After all, if a data encryption key were to be sent to terminal 34 in unencrypted faun, an eavesdropper could use the data encryption key to decrypt the associated data file, thereby circumventing the present invention.
Note that the functionality of the crypto information client is different in terminal 34 than in logger 32. In logger 32, the crypto information client generates the keys and the GUIDs. In terminal 34, the crypto information client uses the GUIDs to fetch the keys. It follows that loggers 32 and terminals 34 could be equipped with different clients. Preferably, however, loggers 32 and terminals 34 use instances of the same crypto information client. This simplifies the design of the present system.
FIG. 5 illustrates the data flow among crypto information server 40 and instances 56 and 66 of the crypto information client according to the present invention. Given a data file to encrypt, instance 56 generates a data encryption key 70 and a corresponding GUID 72. Instance 56 also generates a MAC key 78 that is used to generate a MAC 76 that is embedded in the data file. Data encryption key 70 is used to encrypt the data, including embedded MAC 76, thereby producing an encrypted data file 74. File 74 and GUID 72 are stored in archive 18. Data encryption key 70, MAC key 78 and GUID 72 are sent to crypto information server 40 that stores data encryption key 70, MAC key 78 and QUID 72 in database 38. Upon receipt of encrypted data file 74 and GUID 72 from archive 18, instance 66 sends QUID 72 to crypto information server 40 as part of a request for data encryption key 70. If the request receives authorization, crypto information server 40 fetches data encryption key 70 and MAC key 78 from database 38 according to GUID 72 and sends data encryption key 66 and MAC 78 to instance 66.
The description above of the operation of system 30 is in terms of a single logger 32 and a single user terminal 34. As illustrated in FIG. 2, system 30 almost always includes many loggers 32 and many user terminals 34; but these loggers 32 and user terminals 34 typically operate independently of each other. Crypto information server 40 stores all the encryption keys 70 and all the associated GUIDs 72 in database 38 and sends encryption keys 70 to all terminals 34 contingent on those terminals 34 being authorized to receive encryption keys 70.
FIG. 6 is a high-level schematic block diagram of a second system 100 of the present invention. System 100 is based on the NICE Perform® system available from NICE Systems Ltd. of Raanana, Israel. Specifically, system 100 is a NICE Perform® system modified according to the principles of the present invention. Like a NICE Perform® system, system 100 includes several multimedia loggers 104, several user terminals 112, a controller 106, a storage center 108 and external storage 110, all communicating with each other via a LAN 102.
Loggers 104 capture whatever kind of multichannel data they are configured to capture: voice, VoIP, video and/or screen capture data. The captured data are stored in storage center 108 that functions in a manner similar to archive 18 of systems 10 and 30. Each user terminal includes a screen agent 118 that sends screen capture data to an associated logger 104 and a player application 120 for playing (i.e., displaying) data fetched from storage center 108. Overall control of system 100 is provided by controller 106 that includes a playback media server 114 that mediates between terminals 112 and their potential data sources (loggers 104 and storage center 108) and an audio analysis server 116 that provides audio analysis capabilities such as speech recognition, excitement detection and talk analysis. Optionally, for efficient operation of storage center 108, captured data also are archived in external storage 110. The functionality listed in this paragraph is standard in NICE Perform® systems. More details may be found in the following three documents that are accessible to authorized distributors and customers of NICE Systems Ltd. at http://www.extranice.com:
NICE PerformTM Architecture Overview
NICE PerformTM Solution Overview
NICE PerformTM Solution Brief
To ensure that these three documents remain available for the full life of the patent that is expected to issue from the present patent application, all three documents are reproduced herein in their entirety, as FIGS. 7A through 7T, 8A-1 through 8A-28 and 9A through 9N, respectively.
In addition, loggers 104 include respective instances 124 of a crypto information client of the present invention, user terminals 112 include respective instances 126 of a crypto information client of the present invention and controller 106 includes a crypto information server 122 of the present invention. Crypto information client instances 124 generate data encryption keys and MAC keys for their respective loggers 104. The data encryption keys are generated according to a predefined key granularity. A separate data encryption key and a separate MAC key, with the associated GUID, is generated for each external channel from which data are captured, as well as for each initialization of a screen agent 118. Loggers 104 packetize the captured data, insert respective MACs in the media headers and encrypt the packets to provide encrypted data that are stored in storage center 108 along with associated GUIDs. Controller 106 stores the data encryption keys, the MAC keys and the associated GUIDs in a key database 128. When a user of a user terminal 112 wants to play back stored data, the user fetches the data and its GUID from storage center 108. The user then sends the GUID to controller 106 to request the associated keys. Crypto information client instance 126 of that user terminal 112 negotiates with crypto information server 122 as described above to authorize the sending of the keys to user terminal 112.
While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made. For example, the data logging and data storing functionality of logger 32 can be partitioned between a telcom stage and a recorder stage, as taught in the Henits patent.

## Claims

1. A method for secure recording of screen data, the method comprising the steps of:
generating, at a logger, a data encryption key for each initialization of a screen agent on a terminal, wherein the logger is separate from the terminal and associated with the screen agent on the terminal and receives screen data captured by the screen agent, wherein the data encryption key is used to encrypt according to a predefined granularity the screen data captured as a result of the initialization of the screen agent on the terminal;
using the encryption key to encrypt the screen data to produce encrypted screen data;
associating an identifier with the encryption key and the encrypted screen data;
sending the identifier and the encrypted screen data to an archive; and
sending the identifier and the data encryption key to a crypto information server.

2. The method of claim 1, comprising:
receiving from the archive the encrypted screen data and the identifier;
sending the identifier to the crypto information server;
receiving from the crypto information server the data encryption key; and
decrypting and displaying the screen data.

3. The method of claim 1, comprising, at the crypto information server, authenticating a terminal sending the identifier to the crypto information server.

4. The method of claim 1, comprising receiving the data encryption key in encrypted form.

5. The method of claim 1, comprising:
generating a message authentication code (MAC) key;
using the MAC key to produce a MAC related to the screen data;
attaching the MAC to the screen data prior to encrypting the screen data; and
sending the MAC key to the crypto information server.

6. A method for secure recording of audio data, the method comprising the steps of:
generating a data encryption key for each audio recording channel of a logger, wherein the data encryption key is used to encrypt audio data according to a predefined granularity for the audio recording channel of the logger;
using the encryption key to encrypt the audio data to produce encrypted audio data;
associating an identifier with the encryption key and the encrypted audio data;
sending the identifier and the encrypted audio data to an archive; and
sending the identifier and the data encryption key to a crypto information server.

7. The method of claim 6, comprising:
receiving from the archive the encrypted audio data and the identifier;
sending the identifier to the crypto information server;
receiving from the crypto information server the data encryption key; and
decrypting and audibly presenting the audio data.

8. The method of claim 6, comprising, at the crypto information server, authenticating a terminal sending the identifier to the crypto information server.

9. The method of claim 6, comprising receiving the data encryption key in encrypted form.

10. The method of claim 6, comprising:
generating a message authentication code (MAC) key;
using the MAC key to produce a MAC related to the audio data;
attaching the MAC to the audio data prior to encrypting the audio data; and
sending the MAC key to the crypto information server.

11. A system for secure recording of screen data, the system comprising:
an archive;
a crypto information server;
a data terminal; and
a logger to:
generate a data encryption key for encrypting the screen data captured as a result of each initialization of a screen agent on a terminal, wherein the logger is separate from the terminal and associated with the screen agent on the terminal and receives screen data captured by the screen agent and wherein the data encryption key is used to encrypt according to a predefined granularity the screen data captured as a result of the initialization of the screen agent on the terminal;
use the encryption key to encrypt the screen data to produce encrypted screen data;
associate an identifier with the encryption key and the encrypted screen data;
send the identifier and the encrypted screen data to the archive; and
send the identifier and the data encryption key to the crypto information server.

12. The system of claim 11, wherein the data terminal is to:
receive from the archive the encrypted screen data and the identifier;
send the identifier to the crypto information server;
receive from the crypto information server the data encryption key; and
decrypt and display the screen data.

13. The system of claim 11, wherein the crypto information server is to authenticate the terminal after the terminal sends the data encryption key to the crypto information server.

14. The system of claim 11, wherein the terminal is to receive the data encryption key in encrypted form.

15. The system of claim 11, wherein the logger is to:
generate a message authentication code key;
generate a message authentication code, using the respective message authentication code key; and
attach the message authentication code to the screen data prior to encrypting the screen data;

and wherein the system comprises:
a crypto information server, operative:
to authenticate the terminal; and
contingent on the authentication, to send the respective data encryption key and the respective message authentication code key to the terminal.

16. A system for secure recording audio data, the system comprising:
an archive;
a crypto information server;
a data terminal; and
a logger to:
generate a data encryption key for each audio recording channel of a logger, wherein the data encryption key is used to encrypt audio data according to a predefined granularity for the audio recording channel of the logger;
use the encryption key to encrypt the audio data to produce encrypted audio data;
associate an identifier with the encryption key and the encrypted audio data;
send the identifier and the encrypted audio data to the archive; and
send the identifier and the data encryption key to the crypto information server.

17. The system of claim 16, wherein the data terminal is to:
receive from the archive the encrypted audio data and the identifier;
send the identifier to the crypto information server;
receive from the crypto information server the data encryption key; and
decrypt and audibly present the audio data.

18. The system of claim 16, wherein the crypto information server is to authenticate the terminal after the terminal sends the identifier to the crypto information server.

19. The system of claim 16, wherein the terminal is to receive the data encryption key in encrypted form.

20. The method of claim 1, wherein the granularity is predefined for generating a data encryption key for screen data captured periodically.

21. The method of claim 6, wherein the granularity is predefined for generating a data encryption key for audio data recorded per telephone conversation.

22. The method of claim 6, wherein the granularity is predefined for generating a data encryption key for audio data recorded periodically.

23. A method for secure recording of screen data, the method comprising the steps of:
generating a separate data encryption key for each initialization of a screen agent on each of a plurality of terminals, wherein the data encryption key is used to encrypt according to a predefined granularity the screen data captured as a result of the initialization of the screen agent on the terminal;
using the encryption key to encrypt the screen data to produce encrypted screen data;
associating an identifier with the encryption key and the encrypted screen data;
sending the identifier and the encrypted screen data to an archive; and
sending the identifier and the data encryption key to a crypto information server.