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| − | The call data (known as Intercept Related Information or [[IRI]] in Europe and Call Data or CD in the US) consists of information about the targeted communications, including destination of a voice call (e.g., called party’s telephone number), source of a call (caller’s phone number), time of the call, duration, etc.
| + | #REDIRECT [[Lawful Interception]] |
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| − | ==IRI records==
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| − | * Lawful Interception, a feature as provided by service providers, requires law enforcement agency to first meet Lawful Interception Requirements by providing:
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| − | ** A list of targets
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| − | *** Type of intercepted targets can be from: PSTN, ISDN, GSM (CS), TETRA, GPRS (PD), UMTS (CS)
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| − | ** LIID (unique identifier) for the target
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| − | ** Phone number (calling or called number) of the target
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| − | ** Start/end date and time for the interception
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| − | * Service provider updates targets list in it’s equipments
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| − | * The equipments detect a matching calling or called number, and activates the interception
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| − | * Lawful Interception, then allows law enforcement agencies to intercept calls
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| − | ** By receiving a copy of the audio of both parties, through CC link (forked call) which is a call toward the agency, carrying intercepted audio
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| − | ** By receiving call information records (or IRI records)
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| − | * Intercept Related Information record (IRI record) is a CDR-style record that contain IRI information on an intercepted call
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| − | ==IRI records generating==
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| − | [[Image:Lawful-intercept-details.png|thumb|360px|Schematic showing interception of a call already routed with a Tmedia]]
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| − | * IRI records are generated at various states of the interception
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| − | * They provide information on the interception, and call state
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| − | * In a call, each call leg can be an interception target
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| − | * When a leg is an interception target, it’s intercepted:
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| − | ** Audio «from» this leg is forked to a new outgoing call toward the agency
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| − | ** Audio «to» this leg is forked to a new outgoing call toward the agency
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| − | ** IRI records are generated for this interception
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| − | * Both legs may be independently and simultaneously intercepted
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| − | ** 2 pairs of forked audio outgoing calls
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| − | ** 2 sets of IRI records
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| − | ==Types of IRI records==
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| − | * Start: Indicate that the interception is starting at first event of the communication attempt
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| − | * Continue: Indicate call state change at any time during the communication (attempt)
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| − | * End: Indicate the end of the interception at the end of the communication (attempt)
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| − | * Report: For any non-communication related events
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| − | ===Typical information found in an IRI record===
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| − | * Record type (Start, Continue, End, Report)
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| − | * LIID (unique identifier of the intercepted target assigned by an agency)
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| − | * CIN (communication identity number)
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| − | * Operator identifier
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| − | * Direction (target is originating, or terminating)
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| − | * Call state (idle, setup, connected)
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| − | * Duration of ring and conversation states
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| − | * Calling / called party numbers
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| − | * Release reason
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| − | * CC link state (setup, active, released, lack of resources)
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| − | * CC link release reason
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| − | ==IRI records encoding==
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| − | * IRI records are encoded in ASN.1 format
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| − | * ASN.1 IDs and objects hierarchy for encoding IRI records is provided by ETSI specifications
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| − | ==IRI records values and files specification==
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| − | * IRI records values can be
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| − | ** Mandatory in each record
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| − | ** In one record only for the whole call
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| − | ** optional (in some records only, or none at all)
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| − | * IRI record files can
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| − | ** Contain only one IRI record (one file per record)
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| − | ** Contain multiple IRI records (grouped)
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| − | ==IRI records uploading to the agency==
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| − | * As files, using the FTP protocol
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| − | * Telcobridges supports SFTP as file transfer method as well
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| − | == References ==
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| − | [http://en.wikipedia.org/wiki/Lawful_interception Wikipedia lawful intercept article]
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| − | [[category:Tmedia_Features]]
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| − | [[category:Needs revising]]
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