5.2 Deactivation

03.333G security3GPPLawful InterceptionStage 2TS

The following picture shows the information flow for the deactivation of the Lawful interception.

5.2.1 X1_1-interface

The messages sent from the ADMF to the MSC/VLR and GMSC for deactivation contains:

– the identity of the target;

– the possible relevant IAs in case of location dependent interception.

Figure 6: Information flow on X1_1-interface for Lawful Interception deactivation

If interception of a target has been activated via different identities then a separate deactivation message will need to be sent from the ADMF to the MSC/VLR and the GMSC for each identity.

When several LEAs requested activation on the same identity and subsequently request deactivation then the ADMF determines that there are remaining activations on the identity. In this case, the ADMF will not send a deactivation message to the MSC/VLR and the GMSC except when the activation needs to change from IP and IRI to IP only or IRI only. In that case an activation change message will be sent to the MSC/VLR and the GMSC.

5.2.2 X1_2-interface (IRI)

The ADMF sent for the deactivation to the Delivery Function 2 of the Intercept Related Information:

– a DF2 activation id, which uniquely identifies the activation to be deactivated for DF2.

If a target is intercepted by several LEAs and/or several identities simultaneously, a single deactivation is necessary for each combination of LEA and identity.

Figure 7: Information flow on X1_2-interface for Lawful Interception deactivation

5.2.3 X1_3-interface (IP)

For the deactivating the delivery of the IP the message from the ADMF to the Delivery Function contains:

– a DF3 activation id, which uniquely identifies the activation to be deactivated for DF3.

If a target is intercepted by several LEAs and/or several identities simultaneously, a single deactivation is necessary for each combination of LEA and identity.

Figure 8: Information flow on X1_3-interface for Lawful Interception deactivation