Using signal characteristics to determine the physical location of devices in a data network

• US 7,898,977 B2
• Filed: 02/28/2003
• Issued: 03/01/2011
• Est. Priority Date: 03/01/2002
• Status: Active Grant

• Current Assignee: Extreme Networks, Inc.
• Original Assignee: Enterasys Networks Incorporated (Extreme Networks, Inc.)
• Inventors: Gorsky, John-Paul, Durand, Roger P., Graham, Richard W., Roese, John J.
• Primary Examiner(s): Sheikh, Ayaz R
• Assistant Examiner(s): Wong, Blanche
• Application Number:
  US10/377,299
• Publication Number:
  US 20030216144A1
• Time in Patent Office: 2,923 Days
• Field of Search: None
• US Class Current: 370/254
• CPC Class Codes: G01S 5/02 using radio waves using satellite radio beacon systems for determining position G01S19/00
• CPC Class Codes: H04L 41/0213 Standardised network management protocols, e.g. simple network management protocol [SNMP]
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies
• CPC Class Codes: H04L 61/10 of different types
• CPC Class Codes: H04L 63/02 for separating internal from external traffic, e.g. firewalls
• CPC Class Codes: H04L 63/0492 by using a location-limited connection, e.g. near-field communication or limited proximity of entities
• CPC Class Codes: H04L 63/08 for authentication of entities cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32
• CPC Class Codes: H04L 63/10 for controlling access to devices or network resources
• CPC Class Codes: H04L 63/104 Grouping of entities
• CPC Class Codes: H04L 63/107 wherein the security policies are location-dependent, e.g. entities privileges depend on current location or allowing specific operations only from locally connected terminals
• CPC Class Codes: H04L 63/126 the source of the received data
• CPC Class Codes: H04L 67/04 specially adapted for terminals or networks with limited capabilities; specially adapted for terminal portability
• CPC Class Codes: H04L 67/51 Discovery or management thereof, e.g. service location protocol [SLP] or web services
• CPC Class Codes: H04L 67/52 specially adapted for the location of the user terminal
• CPC Class Codes: H04L 67/63 Routing a service request depending on the request content or context
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 4/20 Services signaling; Auxiliary data signalling, i.e. transmitting data via a non-traffic channel
• CPC Class Codes: H04W 4/50 : Service provisioning or reconfiguring
• 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 8/26 : Network addressing or numbering for mobility support
• CPC Class Codes: Y10S 707/99932 : Access augmentation or optimizing
• CPC Class Codes: Y10S 707/99939 : Privileged access

Abstract

A method of determining a physical location of a device connected to a data network infrastructure including a plurality of connection points at different physical locations, the method including establishing a connection with the data network infrastructure via a cable-based transmission medium, wherein a communication signal passes via the cable-based transmission medium including at least one of the plurality of connection points. A connection point identifier is determined based, at least in part, upon the at least one of the plurality of connection points. A signal characteristic of the communication signal passing via the cable-based transmission medium between the device and the data network infrastructure through the at least one of the plurality of connection points is measured. A first physical location of the device is determined based on the determined connection point identifier, including accessing stored information associating the determined connection point identifier with location information. A second physical location of the device is determined based on the determined first physical location and the measured signal characteristic, including accessing stored information associating signal characteristics with location information.

Claims

1. A method of determining a physical location of a device connected to a data network infrastructure including a plurality of fixed connection points fixed at different physical locations, the method comprising:

storing location information of the plurality of fixed connection points and one or more signal characteristics of one or more signals passing through at least a first fixed connection point of the plurality of fixed connection points in the data network infrastructure, wherein the at least the first fixed connection point is connected to a network entry device in the data network infrastructure using a cable-based transmission medium;

establishing a connection between the device and the network entry device in the data network infrastructure via the at least the first fixed connection point, wherein a communication signal passes through the cable-based transmission medium and the at least the first fixed connection point;

utilizing the established connection to determine a connection point identifier based, at least in part, upon the communication signal;

measuring at least a first signal characteristic of the communication signal;

determining a first physical location of the device based on the determined connection point identifier, including accessing the stored location information using the determined connection point identifier; and

determining a second physical location of the device based on the determined first physical location, the at least the first measured signal characteristic, and the one or more stored signal characteristics.

2. The method of claim 1 further comprising identifying the connection point identifier for each of the plurality of fixed connection points.

3. The method of claim 1 further comprising:

storing information associating the measured signal characteristic and its respective connection point.

4. The method of claim 1 wherein determining a second physical location further comprises:

employing a function that relates values for the one or more signal characteristics to respective location information.

5. The method of claim 1 wherein the signal characteristics comprises at least one of time delay, time-domain reflectometry, signal attenuations, and round-trip delay.

6. The method of claim 1 wherein determining the second physical location of the device based on the determined first physical location and the measured signal characteristic includes:

utilizing the measured signal characteristic to determine a position of the device relative to a physical location of the at least one of the plurality of connection points.

7. A method for surveying a data network infrastructure including a plurality of fixed connection points, the method comprising:

for at least one of the plurality of fixed connection points, wherein each of the plurality of fixed connection points provides a cable-based communication path to the data network infrastructure,

determining a signal characteristic on the cable-based communication path for the at least one of the plurality of fixed connection points, wherein the cable-based communication path is between a network entry device and the at least one of the plurality of fixed connection points, and

storing an association between the at least one of the plurality of fixed connection points and the signal characteristic.

8. The method of claim 7 further comprising identifying a connection point identifier for each of the plurality of fixed connection points.

9. The method of claim 7 further comprising connecting a location sensing device to a first of the plurality of fixed connection points and determining a physical location of said first of the plurality of fixed connection points using the location sensing device.

10. The method of claim 9 wherein the location sensing device comprises a GPS receiver.

11. The method of claim 9 further comprising storing an association between the at least one of the plurality of fixed connection points and its determined physical location.

12. The method of claim 7 wherein the signal characteristic comprises at least one of time delay, time-domain reflectometry, signal attenuation, and round-trip delay.

13. The method of claim 7 wherein storing an association between the at least one of the plurality of fixed connection points and the signal characteristic comprises storing the association between the at least one of the plurality of connection points and the signal characteristic on a packet forwarding network device.

14. The method of claim 13 wherein the packet forwarding network device is a first packet forwarding network device configured to connect the cable-based communication path from the at least one of the plurality of connection points to the data network infrastructure.

15. A system comprising:

a location database for storing location information of a plurality of fixed connection points and at least a first signal characteristic of one or more signals passing through at least one of the plurality of fixed connection points in a data network infrastructure;

a network entry device configured to receive a communication signal passing via a cable-based transmission medium from a device communicating with the network entry device through the at least one of the plurality of fixed connection points, wherein the network entry device is further configured to measure one or more signal characteristics of the communication signal; and

a location module, associated with the network entry device and the location database, configured to determine a first physical location of the device based on the at least one of the plurality of fixed connection points, including accessing the stored location information in the location database, and a second physical location of the device based on the determined first physical location and by comparing the one or more measured signal characteristics with at least the first signal characteristic.

16. The system of claim 15 wherein the location module is further configured to employ a function that relates values for the one or more measured signal characteristics to respective physical locations of the at least one of the plurality of connection points.

17. The system of claim 15 wherein the location module further comprises a signal characteristic database having an association of the stored signal characteristics of the one or more signals and the corresponding fixed location for each of the plurality of connection points.

18. The system of claim 17 wherein the location module is further configured to:

access the signal characteristic database to determine the physical location of the at least one of the plurality of connection points; and

utilize the measured signal characteristic to determine a position of the device relative to the determined first physical location of the at least one of the plurality of connection points.

19. The system of claim 15 wherein the measured signal characteristic comprises at least one of time delay, time-domain reflectometry, signal attenuation, and round-trip delay.