Systems and methods for performing authorized intercept in a satellite-based communications system

• US 6,823,185 B1
• Filed: 06/19/2000
• Issued: 11/23/2004
• Est. Priority Date: 06/19/2000
• Status: Expired due to Fees

• Current Assignee: CDC Propriete Intellectuelle
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Carmony, Pamela Tam, Comer, Erwin Perry, Ruppert, William Henry
• Primary Examiner(s): Trost, William
• Assistant Examiner(s): NGUYEN, JOSEPH D
• Application Number:
  US09/596,567
• Time in Patent Office: 1,618 Days
• Field of Search: 455/427, 455/428, 455/430, 455/433, 455/435.1, 455/405, 455/410, 455/12.1, 455/426, 455/422, 455/560, 455/412-414, 455/13.1, 379/7, 379/35, 379/213.01
• US Class Current: 455/427
• CPC Class Codes: H04B 7/185 Space-based or airborne stations; Stations for satellite systemsH04B7/204 takes precedence
• CPC Class Codes: H04L 63/30 for supporting lawful interception, monitoring or retaining of communications or communication related information circuit switched telephony call monitoring H04M3/2281
• CPC Class Codes: H04W 12/03 Protecting confidentiality, e.g. by encryption
• CPC Class Codes: H04W 12/80 Arrangements enabling lawful interception [LI]
• CPC Class Codes: Y10T 428/31616 Next to polyester [e.g., alkyd]

Abstract

Authorized intercepts of communications in a satellite communications system (10) are performed, according to which a law enforcement agency (LEA) can request the intercept of communications to and/or from subscriber units (SUs). In one embodiment, an LEA intercept request causes an intercept order for a particular target SU (420, FIG. 6) to be transmitted to one or more satellites (411-413, FIG. 6), where the intercept order is stored in an intercept table (410). Any communications traffic involving the target SU results in an intercept by a satellite, which routes a copy of the intercepted communications to the requesting LEA, either directly or via an associated intercept facility (426, FIG. 8).

Claims

1. A method of performing communication intercepts in a communications system comprising at least one satellite communications node and a plurality of subscriber units, the method comprising:

maintaining a database of subscriber unit identifiers and jurisdictional information associated with each of the plurality of subscriber units;

selecting one of the plurality of subscriber units as a target subscriber unit;

identifying the at least one satellite communications node associated with the jurisdictional information associated with the target subscriber unit;

transmitting an intercept order comprising the identifier for the target subscriber unit to the identified at least one satellite communications node providing service to the target subscriber unit; and

receiving an intercepted communication with the target subscriber unit from the at least one satellite communications node.

2. The method recited in claim 1 wherein the communications system further comprises a network management facility.

3. The method recited in claim 2 wherein the at least one communications node comprises a memory, the method further comprising:

the at least one satellite communications node storing the intercept order into an intercept table in the memory.

4. The method recited in claim 3 wherein in the selecting operation more than one of the plurality of subscriber units is selected as a target subscriber unit, wherein the selecting operation is performed by at least one intercept requestor having an intercept requestor ID, and wherein the intercept table comprises a list of all target subscriber units within the footprint of the at least one satellite communications node, each target subscriber unit having associated therewith at least one intercept requestor ID.

5. The method recited in claim 2 wherein the identifier comprises an encrypted subscriber unit ID corresponding to the target subscriber unit.

6. The method recited in claim 5 and further comprising:

the at least one satellite communications node determining whether a received communication comprises the subscriber unit ID for the target subscriber unit;

intercepting the communication when said at least one satellite communications node determines said communication comprises said subscriber unit ID; and

transmitting without intercepting the communication when said at least one satellite communications node determines said communication does not comprise said subscriber unit ID.

7. The method recited in claim 6 wherein the communications system further comprises a network intercept facility, and wherein the intercept order comprises a network intercept facility ID identifying the network intercept facility, the method further comprising:

if the at least one satellite communications node intercepts the communication, transmitting the communication to the network intercept facility.

8. The method recited in claim 2 wherein the communications system further comprises a network intercept facility, and wherein the intercept order comprises a network intercept facility ID identifying the network intercept facility, the method further comprising:

the at least one satellite communications node transmitting the communication to the network intercept facility.

9. The method recited in claim 8 wherein the intercept order identifies an intercept requestor, the method further comprising:

the network intercept facility addressing a transmission of the intercepted communication to the intercept requestor.

10. The method recited in claim 8 wherein the intercept order identifies an intercept requestor, the method further comprising:

the network intercept facility providing a transmission of the intercepted communication to the intercept requestor.

11. A satellite communications node for use in a communications system having a plurality of communications nodes, the satellite communications node comprising:

a transceiver to receive communications from one communications node and to transmit communications to another communications node;

a data processing system, including a processing element and a memory, to execute at least one computer program performing intercepts in the communications system, the at least one computer program when executed comprising the operations of;

receiving an intercept order from a network intercept facility, the intercept order comprising a target communications node ID assigned by a network operations facility;

decrypting the intercept order to thereby verify the network intercept facility;

separately decrypting the target communications node ID to the thereby verify the network operations facility;

evaluating a communication received by the transceiver to determine whether it comprises the target communications node ID;

if so, intercepting the communication; and

if not, controlling the transceiver to transmit the communication without intercepting it.

12. The satellite communications node recited in claim 11 wherein the intercept order is stored in an intercept table in the memory.

13. The satellite communications node is recited in claim 11 wherein the intercept order further comprises a start time when evaluating is to start, and wherein evaluating starts at the same time.

14. The satellite communications node is recited in claim 11 wherein the intercept order further comprises a stop time when evaluating is to stop, and wherein evaluating stops at the stop time.

15. The satellite communications node recited in claim 11 wherein at least one computer program when executed comprises the additional operations of:

if the communication is intercepted, generating a communication clone; and

controlling the transceiver to transmit the communication clone to another of the communications nodes.

16. The satellite communications node recited in claim 15 wherein the intercept order further comprises an ID corresponding to the network intercept facility to which a communication clone is to be transmitted, and wherein the transceiver is controlled to transmit the communication clone to the network intercept facility.

17. The satellite communications node recited in claim 16 wherein the intercept order further comprises a start time when evaluating is to start, wherein evaluating starts at the start time, and wherein the start time has a different granularity than a start time stored at the network intercept facility corresponding to the intercept order.

18. The satellite communications node recited in claim 16 wherein the intercept order further comprises a start time when evaluating is to start, wherein evaluating starts at the start time, and wherein the start time has a different granularity than a stop time stored at the network intercept facility corresponding to the intercept order.

19. The satellite communications node recited in claim 15 wherein the intercept order further comprises an ID corresponding to an intercept requestor to which a communication clone is to be transmitted, and wherein the transceiver is controlled to transmit the communication clone to the intercept requestor.

20. A communications facility for use in a communications system comprising a plurality of communications nodes, including a plurality of subscriber nodes and at least one satellite communications node in which communications are intercepted, the communications facility comprising:

a transceiver to receive communications from one communications node and to transmit communications to another communications node;

a data processing system, including a processing element and a memory, the processing element executing at least one computer program stored in the memory, the at least one computer program when executed comprising the operations of;

receiving an encrypted identifier for a target node of the plurality of subscriber nodes from a database associated with a network operations facility responsible for a jurisdiction served by the communications system in which the target node is located;

forming an intercept order comprising the encrypted identifier, wherein the intercept order is encrypted with a key that identifies the communications facility; and

transmitting the intercept order to the at least one satellite communications node providing service to the jurisdiction in which the target node is located.