Interception Of Multimedia Services

• US 20100039946A1
• Filed: 07/01/2005
• Published: 02/18/2010
• Est. Priority Date: 07/01/2005
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Iov 'eno, Maurizio, Imbimbo, Amedeo
• Granted Patent: US 7,843,902 B2
• Time in Patent Office: Days
• US Class Current: 370/252
• CPC Class Codes: H04L 63/306 intercepting packet switched data communications, e.g. Web, Internet or IMS communications
• CPC Class Codes: H04L 65/1016 IP multimedia subsystem [IMS]
• CPC Class Codes: H04L 65/1104 Session initiation protocol [SIP]
• CPC Class Codes: H04L 67/14 Session management for real-time applications in data packet communications networks H04L65/1066
• CPC Class Codes: H04M 3/2281 Call monitoring, e.g. for law enforcement purposes; Call tracing; Detection or prevention of malicious calls

Abstract

The present invention relates to a method for monitoring in a telecommunication system. The system comprises a service domain that handles session control and a bearer domain used for transportation of media flow. A request for monitoring of a first party (A) is received by a Call Session Control Function (CSCF) in the service domain. The method comprises the following further steps: —A SIP session event is detected by the Call 10 Session Control Function (CSCF) due to a set-up of a media-flow connection between the monitored party (A) and a second party (B). —A resource set-up message (SIP1) is sent via an interface (Mr) from the Call Session Control Function (CSCF) to a Multimedia Resource Function (MRF) in the service domain. —A SIP transaction is established between the Multimedia Resource Function (MRF) and a third Delivery Function (DF3). —A SIP session is established between the third Delivery Function (DF3) and a Law Enforcement Monitoring Facility (LEMF).

Claims

1. A method for monitoring in a telecommunication system, which system comprises a service domain that handles session control and a bearer domain used for transportation of media flow, whereby a request for monitoring of a first party is received by a Call Session Control Function in the service domain, which method comprises the following further steps:

a SIP session event is detected by the Call Session Control Function due to a set-up of a media-flow connection between the monitored party and a second party;

CHARACTERISED BY

a resource set-up message is sent via an interface from the Call Session Control Function to a Multimedia Resource Function in the service domain;

a SIP transaction is established between the Multimedia Resource Function and a third Delivery Function;

a SIP session is established between the third Delivery Function and a Law Enforcement Monitoring Facility.

2. The Method for monitoring in a telecommunication system according to claim 1, which method comprises the following further steps:

media-flow between the parties is rerouted to pass the Multimedia Resource Function in the service domain;

a copy of the media-flow is delivered from the Multimedia Resource Function to the Law Enforcement Monitoring Facility via the established SIP transaction/session.

3. The Method for monitoring in a telecommunication system according to claim 2 whereby the delivering of the media-flow is done on a one-way connection.

4. The Method for monitoring in a telecommunication system according to claim 2 whereby the media flow is re-routed from the bearer domain to the Multimedia Resource Function in the service domain.

5. The Method for monitoring in a telecommunication system according to claim 2 whereby the media flow between the parties is arranged to first pass a Media-Gate-Way in the service domain and is then to be re-routed from the Media-Gate-Way to the Multimedia Resource Function in the service domain.

6. The Method for monitoring in a telecommunication system according to claim 1, which method comprises the following further step:

interception Related Information related to the monitored party is transported from the Call Session Control Function to the Law Enforcement Monitoring Facility.

7. The Method for monitoring in a telecommunication system according to claim 6, whereby correlation Information for the Interception Related Information is transferred to the Law Enforcement Monitoring Facility via a second Handover Interface, and CC correlation Information for the Content of Communication is transferred to the Law Enforcement Monitoring Facility via a third Handover Interface, which information comprises a correlation number that is common for both IRI and CC.

8. The Method for monitoring in a telecommunication system according to claim 7, whereby correlation between Interception related Information and Content of Communication is implemented in the Law Enforcement Monitoring Facility.

9. The Method for monitoring in a telecommunication system according to claim 1, whereby also non-monitored media flows always are re-routed via the Multimedia Resource Function.

10. An arrangement for monitoring in a telecommunication system, which system comprises a service domain that handles session control and a bearer domain used for transportation of media flow. whereby a request for monitoring of a first party is received by a Call Session Control Function in the service domain, which arrangement comprises:

means for detecting a SIP session by the Call Session Control Function due to a set-up of a media-flow connection between the monitored party and a second party;

CHARACTERISED BY

means to send a resource set-up message via an interface from the Call Session Control Function to a Multimedia Resource Function in the service domain;

means to establish a SIP transaction between the Multimedia Resource Function and a third Delivery Function;

means to establish a SIP session between the third Delivery Function and a Law Enforcement Monitoring Facility.

11. The arrangement for monitoring in a telecommunication system according to claim 10, which arrangement comprises:

Means to re-route media-flow between the parties to pass the Multimedia Resource Function in the service domain;

Means to deliver a copy of the media-flow from the Multimedia Resource Function to the Law Enforcement Monitoring Facility via the established SIP transaction/session.

12. The arrangement for monitoring in a telecommunication system according to claim 11, which comprises means for delivering the media-flow on a one-way connection.

13. The arrangement for monitoring in a telecommunication system according to claim 11, which comprises means for re-routing the media flow from the bearer domain to the Multimedia Resource Function in the service domain.

14. The arrangement for monitoring in a telecommunication system according to claim 11 whereby the media flow between the parties is arranged to first pass a Media-Gate-Way in the service domain. which comprises means to re-route the media-flow from the Media-Gate-Way to the Multimedia Resource Function in the service domain.

15. The arrangement for monitoring in a telecommunication system according to claim 10, which comprises:

means for transporting interception Related Information related to the monitored party from the Call Session Control Function to the Law Enforcement Monitoring Facility.

16. The arrangement for monitoring in a telecommunication system according to claim 15, which comprises means for transfer IRI correlation Information for the Interception Related Information (IRI) to the Law Enforcement Monitoring Facility via a second Handover Interface, and means for transfer CC correlation Information for the Content of Communication (CC) to the Law Enforcement Monitoring Facility via a third Handover Interface, which information comprises a correlation number that is common for both IRI and CC.

17. The arrangement for monitoring in a telecommunication system according to claim 16, which comprises means to implement correlation between Interception related Information and Content of Communication in the Law Enforcement Monitoring Facility.

18. The arrangement for monitoring in a telecommunication system according to claim 10, which comprises means to always re-route non-monitored media flows always via the Multimedia Resource Function.