Default LI Support

Overview

Call content is sent from the SBC to the IS in an RTP media stream for each direction of an intercepted call. Call content will always be sent to the IP addresses and UDP ports specified by the intercept server in the Signaling Start Response message. The IS decides if it is sent to the LEA based on the configured warrant. The intercept server performs in-band tone detection and sends the appropriate call data messages to the LEA for this detection. The IS detects RFC2833 DTMF Relay RTP packets and sends the appropriate call data messages to the LEA. SBC detects out of band tones and sends the appropriate call data messages to the IS. The IS performs any gateway function of the audio signal required by the LEA before sending the call content to the LEA.

In some call scenarios, Ribbon network elements are not part of the media path. This is referred to as "direct media." When LI and "direct media" are configured on the SBC, Lawful intercept takes precedence, and any direct media calls are converted to ordinary pass-through calls.

Intercept criteria are identified by an "Intercept_Criteria_Type" and "Intercept_Criteria" (or criteria ID) attribute. The SBC currently supports the following intercept criteria types:

• Directory Number
• SIP URI

Associated with each intercept type are corresponding criteria IDs.

• If Intercept_Criteria_Type is "Directory Number", then the criteria IDs are "Country Code" and "National Id".
• If the Intercept_Criteria_Type is "SIP URI", then the criteria ID is "SIP URI".

To configure LI, see following pages:

• EMA: refer to Address Context - Lawful Intercept
• CLI: refer to Intercept - CLI

Centralized PSX Solution

Solution details:

• Required network elements: external PSX, IS and EMS.
• User "calea" must be created on SBC before attempting LI provisioning.
• User must login as "calea" in PSX to do LI CDC provisioning and target settings.
• LI is not supported for Video and SRTP calls. For LI CDC provisioning, the SBC node must be registered with "calea" and appropriate password instead of using default "admin/admin" as the Agent login and password.

A separate license is required on EMS and/or SBC to enable this service. Without these licenses, the APIs for this feature are not accessible. Only authorized users can access LI functions.

The following Centralized PSX diagram includes the SBC 5000 series for the example.

Figure 1: LI Provisioning Diagram (Centralized PSX)

For EMS-related LI configurations, please see Ribbon Insight User Guide and Insight Lawful Intercept Guide located at Insight EMS Documentation.

SBC ERE Solution

The SBC ERE solution includes the following requirements:

• Required network elements: EMA, IS and ERE.
• User "calea" must be created on SBC before attempting LI provisioning.
• User must login as "calea" in EMA to do LI CDC provisioning and target settings.
• The "calea" username and appropriate password must be used on the LI server to perform LI target provisioning as opposed to default username/password (calea/calea).

Figure 2: LI Provisioning Diagram (SBC ERE Solution)

For EMA-related LI configurations, please see EMA User Guide.