Methods and systems for obscuring network topologies

• US 8,600,349 B2
• Filed: 02/11/2009
• Issued: 12/03/2013
• Est. Priority Date: 07/08/2008
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Willars, Per, Bolin, Johan, Wigren, Torbjorn
• Primary Examiner(s): Afshar, Kamran
• Assistant Examiner(s): TRAN, MONG-THUY THI
• Application Number:
  US13/002,817
• Publication Number:
  US 20110116632A1
• Time in Patent Office: 1,756 Days
• Field of Search: 455/410, 455/411, 455/444, 455/446, 455/443, 455/449, 455/422.1, 455/423, 455/424, 455/428, 455/560, 370/254
• US Class Current: 455/410
• CPC Class Codes: H04L 63/04 for providing a confidential data exchange among entities communicating through data packet networks
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 8/16 selectively restricting mobility data tracking
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support

Abstract

Node, computer software and method for preventing an external party (114) to map an identity of a network cell (122) of a telecommunication network (112 or 120) with a corresponding geographical location of the network cell (122). The method includes receiving at a base station (200) of the telecommunication network (112 or 120) system information from a radio network controller (203) of the telecommunication network (112 or 120); extracting, at the base station (200), the identity of the network cell (122) from the received system information; changing, at the base station (200), the identity or one of multiple parts of the identity of the network cell (122); and sending the changed identity or the one of multiple parts of the identity to a user terminal (80).

Claims

1. A method for preventing an external party to map an identity of a network cell of a telecommunication network with a corresponding geographical location of the network cell, the method comprising:

receiving at a base station of the telecommunication network system information from a radio network controller of the telecommunication network;

extracting, at the base station, the identity of the network cell from the received system information;

changing, at the base station, the identity or one of multiple parts of the identity of the network cell; and

sending the changed identity or the one of multiple parts of the identity to a user terminal, wherein the changing step further comprises;

generating a new identity for the network cell, wherein the new identity has multiple parts;

changing in the radio network controller a current identity of the network cell with the new identity; and

instructing the base station, which is controlled by the radio network controller and which controls the network cell, to replace a current second portion of the current identity with a new second portion of the new identity of the network cell.

2. The method of claim 1, wherein the changing step further comprises:

receiving at the base station a scrambling key from the radio network controller; and

scrambling at least a portion of the extracted network cell identity based on the scrambling key.

3. The method of claim 2, further comprising:

regularly receiving the scrambling key from the radio network controller.

4. The method of claim 2, further comprising:

randomly receiving the scrambling key from the radio network controller.

5. The method of claim 2, wherein all parts of the identity are scrambled.

6. The method of claim 1, wherein the identity of the network cell extracted from the received system information comprises a radio network controller identifier (RNC-id) and a cell identifier (C-id).

7. The method of claim 1, wherein the changing step further comprises:

generating at the base station a scrambling code; and

scrambling the identity or the one of multiple parts of the identity of the network cell based on the scrambling code.

8. The method of claim 7, further comprising:

monitoring a timer in the base station for determining when to change the scrambling code; and

regularly changing the scrambling code.

9. The method of claim 7, further comprising:

randomly changing the scrambling code.

10. The method of claim 1, further comprising:

changing simultaneously identities of plural network cells.

11. The method of claim 10, further comprising:

changing simultaneously identities of less than all plural network cells served by the base station.

12. The method of claim 1, further comprising:

determining in the radio network controller of the telecommunication network when to change the identity of the network cell.

13. The method of claim 1, further comprising:

repeating the above steps for each network cell controlled by the radio network controller.

14. The method of claim 1, further comprising:

searching other network cells that are related to the current identity of the network cell in corresponding neighbor lists.

15. The method of claim 14, further comprising:

replacing in those neighbor lists in the radio network controller that include the current identity of the network cell with the new identity; and

replacing in cell configurations stored in the radio network controller the current identity of the network cell with the new identity.

16. A base station of a telecommunication network configured to prevent an external party to map an identity of a network cell of the telecommunication network with a corresponding geographical location of the network cell, the base station comprising:

a communication interface configured to receive system information from a radio network controller of the telecommunication network; and

a processor configured to,

extract the identity of the network cell from the received system information,

change the identity or one of multiple parts of the identity of the network cell, and

send the changed identity or the one of multiple parts of the identity to a user terminal, wherein

the processor is configured to change the identity or one of multiple parts of the identity of the network cell by implementing an instruction transmitted from the radio network controller, the instruction instructing the base station, which is controlled by the radio network controller and which controls the network cell, to replace a current second portion of the current identity with a new second portion of a new identity of the network cell generated by the radio network controller, wherein the new identity has multiple parts, and the radio network controller is configured to change the current identity of the network cell with the new identity.

17. The base station of claim 16, wherein the processor is further configured to:

receive a scrambling key from the radio network controller; and

scramble the identity or the one of multiple parts of the identity based on the scrambling key.

18. The base station of claim 16, wherein the processor is further configured to:

generate at the base station a scrambling code, and

scramble the identity or the one of multiple parts of the identity of the network cell based on the scrambling code.

19. A non-transitory computer readable medium including computer executable instructions, wherein the instructions, when executed, implement a method for preventing an external party to map an identity of a network cell of a telecommunication network with a corresponding geographical location of the network cell, the method comprising:

receiving at a base station of the telecommunication network system information from a radio network controller of the telecommunication network;

extracting, at the base station, the identity of the network cell from the received system information;

changing, at the base station, the identity or one of multiple parts of the identity of the network cell; and

sending the changed identity or the one of multiple parts of the identity to a user terminal, wherein

the changing step comprises implementing an instruction transmitted from the radio network controller, the instruction instructing the base station, which is controlled by the radio network controller and which controls the network cell, to replace a current second portion of the current identity with a new second portion of a new identity of the network cell generated by the radio network controller, wherein the new identity has multiple parts, and the radio network controller is configured to change the current identity of the network cell with the new identity.