Universal personal communication system and tracing system therefor

• US 5,274,845 A
• Filed: 01/03/1992
• Issued: 12/28/1993
• Est. Priority Date: 01/03/1992
• Status: Expired due to Fees

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Wang, Zhonghe
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): FAILE, ANDREW I
• Application Number:
  US07/817,018
• Time in Patent Office: 725 Days
• Field of Search: 455/12.1, 455/13.1, 455/13.2, 455/33.1, 455/34.1, 455/54.1, 455/54.2, 455/56.1, 455/33.2, 455/33.3, 455/33.4, 455/67.1, 379/59, 340/825.21, 340/825.52, 340/825.49
• US Class Current: 455/461
• CPC Class Codes: H04W 60/00 Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
• CPC Class Codes: H04W 8/085 involving hierarchical organized mobility servers, e.g. hierarchical mobile IP [HMIP]

Abstract

A communication system includes a plurality of organizational layers, a plurality of portable communication units, and a plurality of base stations. Each layer comprises a plurality of nodes. The plurality of nodes includes a plurality of base stations in the first layer, and a plurality of communication services nodes organized into higher layers. Each communication services node includes a database possibly containing information on the locations of one or more portable communication units. The databases constitute a distributed database containing the necessary and sufficient information on the locations of some of the portable communication units within the system, such that any active portable communication unit in its service area will be located using the most direct route. A tracing strategy is realized by the transmission of control messages informing the system of a moving portable communication unit'"'"'s location. The system tries to set up a connection to the home address of the called portable communication unit, unless some information is found along the path to the home address of the called unit. In case there is information on the called unit its location is indicated by the address chain in the distributed database.

Claims

1. A communication system comprising:

a plurality of portable communication units and a plurality of stationary communication units;

a plurality of nodes organized into a plurality of layers, the plurality of layers arranged into a first layer and a plurality of higher layers, the first layer having an integer value equal to one associated therewith and each of said plurality of higher layers having an integer greater than one associated therewith, and the plurality of nodes including;

a plurality of base stations organized into the first layer; and

a plurality of communication service nodes organized into the plurality of higher layers; and

a plurality of databases,

wherein each of said plurality of base stations and each of said plurality of communication service nodes is assigned to unique parent nodes, said unique parent nodes being a unique ones of said plurality of communication services nodes at ones of said plurality of levels having an integer associated therewith that is greater than the integer associated with the one of said plurality of layers that said each of said plurality of base stations or said each of said plurality of communication service nodes is organized into, and

wherein each of said plurality of portable communication units has a home address and a physical address associated therewith, and wherein each physical address comprises a current address and a new address, each of said physical address and current address indicating one of said plurality of base stations and unique parent nodes assigned thereto, and

wherein each of said plurality of communication service nodes has one of the plurality of databases associated therewith, each of said plurality of databases for storing said home address and said physical address of said plurality of portable communication units, one of said plurality of portable communication units communicating with one of said plurality of communication service nodes associated with one of said plurality of databases when said one of said plurality of databases has stored therein said home address associated with said one of said plurality of portable communication units.

2. In a communication system comprising a plurality of portable communication units, a plurality of base stations organized into a first layer, i=1, and a plurality of communication service nodes organized into a plurality of higher layers, i>

1, where i is an integer, each portable communication unit including a home address and a physical address associated therewith, each physical address comprising a current address and a new address, and each communication service node in a layer, other than the first, having a database associated therewith, each base station and each lower layer communication service node having a unique parent node in each of the higher levels, a process for establishing a connection between a calling communication unit and a called communication unit comprising the steps of;

(a) receiving a connection request, at a base station or communication service node in layer i, the connection request requesting the establishment of a communication link between the calling communication unit and the called communication unit;

(b) determining whether layer i is in the first layer, and whether the connection request was received from a portable communication unit;

(c) calling the called communication unit when the connection request was received by a communication service node in the first layer, and the connection request was not received directly from a portable communication unit;

(d) determining whether a connection confirmation has been received from the called communication unit within a predetermined period;

(e) establishing the communication link when connection confirmation has been received from the called communication unit within a predetermined period and stopping the process for the first layer node; and

(f) reporting a communication failure to the communication system, when the determination of step (d) is negative and stopping the process for the first layer node.

3. The process of claim 2, further comprising the steps of:

(g) determining whether layer i is the first layer, when it is determined in step (b) that the connection request was received directly from a portable communication unit, or that i is greater than one; and

(h) passing the connection request to its second layer parent communication service node, when the determination of step (g) is affirmative and stopping the process for the first layer node.

4. The process of claim 3, further comprising the step of:

(i) determining whether there is an entry relating to the called communication unit in the database of the communication service node receiving the connection request, if it is determined in step (g) that layer i is not the first layer.

5. The process of claim 3, further comprising the steps of:

(j) passing the connection request to the communication service node or the base station whose address is indicated in the address field of the associated item in the database, when the determination of step (i) is affirmative and stopping the process for the layer i node; and

(k) passing the connection request to the next layer node along the path leading to the called communication unit'"'"'home address, when the determination of step (i) is negative and stopping the process for the layer i node.

6. In a communication system comprising a plurality of portable and stationary communication units each operating in a service area defined by a user of a communication unit, a plurality of nodes including a plurality of base stations which form a first layer for the communication system, and a plurality of communication service nodes organized into a plurality of higher layers, each portable communication unit including a home address and a physical address associated therewith, each physical address comprising a current address and a new address, each communication service node comprises a database of portable communication unit addresses, and each base station and lower layer communication service node having a unique parent node in each of the higher levels, a process for maintaining each database comprising the steps of:

(a) transmitting a first message with a portable communication unit to a base station in a second cell as the portable communication unit moves out of a first cell and into the second cell and when;

the current address and the new address of the portable communication unit are within the service area of the portable communication unit, and

the new address and the home address of the portable communication unit are not the same at the first layer,

the first message including the current address, the new address and the home address for informing the base station in the second cell that the portable communication unit is going to lock to the base station;

(b) transmitting a second message with a portable communication unit to a base station in the first cell when the portable communication unit moves out of the first cell and into the second cell, and when the current address and the new address of the portable communication unit are within the service area of the portable communication unit, and the current address and the home address of the portable communication unit are not the same at the first layer, the second message including the current address, the new address, and the home address of the portable communication unit for informing the base station in the first cell that the portable is leaving the first cell.

7. The process of claim 6, further comprising the step of:

(c) transmitting a third message with a portable communication unit to a base station that the portable communication unit is locked on to, when the portable is not in its home address and any one of the following conditions occurs;

the portable is turned off inside its service area;

or

the portable communication unit is moving out of its service area;

the third message including the current address, and the home address of the portable communication unit, and the third message informing the system that the portable communication unit is leaving the communication system.

8. The process of claim 6, further comprising the step of:

(d) transmitting a fourth message with a portable communication unit to a selected base station within its service area when;

the portable'"'"'s home address is not within the selected cell; and

the portable is moving into the selected cell from an area that is not in a service area for the portable, or the portable communication unit is activated inside its service area;

the fourth message including the new address, and the home address of the portable communication unit, and the fourth message informing the system that the portable communication unit is entering the communication system.

9. The process of claim 6, wherein the first message is received in a node in layer i, where i is an integer greater than or equal to one, and step (a) further comprises the steps of:

(a1) determining whether i is less than or equal to the number of the highest layer where the new and current addresses of the portable communication unit are different;

(a2) sending the first message to its layer i+1 parent communication service node when the determination of step (a1) is affirmative;

(a3) determining whether i is greater than one;

(a4) determining whether there is an entry for the portable communication unit in the database of the layer i node, when the determination of step (a3) is affirmative;

(a5) determining whether the new address and the home address of the portable communication unit are the same at the i-1 layer, when the determination of step (a4) is affirmative;

(a6) removing an entry relating to the portable communication unit at the database of the layer i node when the determination of step (a5) is affirmative, and stopping the process for the communication service node in layer i; and

(a7) stopping the process for the communication service node in layer i, when the determination of step a(3) is negative.

10. The process of claim 9, further comprising the steps of

(a8) determining whether i is equal to the sum of one and the number of the highest layer where the new address and the current address of the portable communication unit are different, when the determination of step (a1) is negative;

(a9) proceeding to step (a3) when the determination of step (a8) is affirmative; and

(a10) determining that an error exists when the determination of step (a8) is negative.

11. The process of claim 10 further comprising the following step, after step (a5):

(a11) updating the i-1 layer address relating to the portable communication unit when the determination of step (a5) is negative, and the process stops for the layer i node.

12. The process of claim 11, further comprising the following steps:

(a12) adding a new entry with the address indicating the layer i-1 new address of the portable communication unit, and stopping the process for the layer i communication services node, when the determination of step (a4) is negative.

13. The process of claim 6, wherein the second message is received in a base station or a communication service node in layer i, and step (b) further comprises the steps of:

(b1) determining whether i is less than the number of the highest layer where the new address and the current address of the portable communication unit are different;

(b2) sending the second message to its layer i+1 parent node, when the determination of step (b1) is affirmative;

(b3) determining whether i is greater than 1;

(b4) determining whether the current address and the home address of the portable communication unit are the same at layer i, when the determination of step (b3) is affirmative; and

(b5) adding a new entry relating to the portable communication unit with an out mark in the database at the layer i node, the out mark indicating that the portable communication unit is not at its home address, when the determination of step (b4) is affirmative, and stopping the process for the layer i communication services node.

14. The process of claim 13, further comprising the following step, after step (b1):

(b6) proceeding to step (b3) when the determination of step (b1) is negative.

15. The process of claim 14, further comprising the following steps, after step (b4):

(b7) determining whether the first layer is the highest layer where the current address and the new address of the portable communication unit are different, when the determination of step (b4) is negative; and

(b8) removing an entry relating to the portable communication unit in the database of the layer i node, and stopping the process for the layer i communication services node when the determination of step (b7) is negative;

(b9) stopping the process for the layer i communication services node when the determination of stop (b7) is affirmative; and

(b10) stopping the process for the layer i communication services node when the determination of step (b3) is negative.

16. The process of claim 7, wherein the third message is received in a node in layer i, and step (c) further comprises the steps of:

(c1) determining whether i is greater than one;

(c2) determining whether the current address and the address of the node, at which the third message was received, are the same at layer i, and whether i is less than or equal to the number of the highest layer where the current address and the home address of the portable communication unit are different, when the determination of step (c1) is affirmative;

(c3) sending the third message to its parent communication services node at the i+1 layer, when the determination of step (c2) is affirmative; and

(c4) removing an entry relating to the portable communication unit from the database of the node in which the third message was received, and stopping the process for the layer i communication services node.

17. The process of claim 16 further comprising the following steps, after step (c2):

(c5) determining whether the home address of the portable communication unit and the address of the node in which the third message was received are the same at layer i, and whether i is greater than two, when the determination of step (c2) is negative; and

(c6) sending the third message to its layer i-1 child node along the path leading to the home address of the portable communication unit, and proceeding to step (c4) when the determination of step (c5) is affirmative.

18. The process of claim 17 further comprising the following step, after step (c1):

(c7) sending the third message to its second layer parent node, and stopping the process for the node in the first layer when the determination of step (c1) is negative.

19. The process of claim 8, wherein the node is in layer i, and step (d) further comprises the following steps:

(d1) determining whether i is greater than one;

(d2) determining whether i equals two, and whether the new address of the portable communication unit and the address of the node at which the fourth message was received, are the same at layer i when the determination of step (d1) is affirmative;

(d3) determining whether the portable communication unit is authentic when the determination of step (d2) is affirmative;

(d4) determining whether the new address of the portable communication unit and the address of the node at which the fourth message was received, are the same at layer i, when the determination of step (d3) is affirmative;

(d5) determining whether i is less than or equal to the number of the highest layer where the new address and the home address of the portable communication unit are different, when the determination of step (d4) is affirmative;

(d6) sending the fourth message to its layer i+1 parent node, when the determination of step (d5) is affirmative;

(d7) adding an entry with the layer i-1 address of the portable communication unit, and stopping the process for the layer i communication services node; and

(d8) determining whether i is greater than two when the determination of step (d5) is negative; and

(d9) proceeding to step (d7) when step (d8) is negative.

20. The process of claim 19 further comprising the following steps, after step (d8):

(d10) sending the fourth message to the layer i-1 child communication services node along a path leading to the home address of the portable communication unit, and proceeding to step (d7), when the determination of step (d8) is affirmative.

21. The process of claim 20, further comprising the following step, after step (d1):

(d11) sending the fourth message to its second layer parent communication services node, and stopping the process for the first layer communication services node, when the determination of step (d1) is negative.

22. The process of claim 21 further comprising the following step, after steps (d4):

(d12) determining whether the home address of the portable communication unit and the address of the node at which the fourth message was received, are the same at layer i, when the determination of step (d4) is negative;

(d13) determining whether i is greater than two when the determination of step (d12) is affirmative;

(d14) sending the fourth message to the layer i-1 child communication services node along a path leading to home address of the portable communication unit, when the determination of step (d13) is affirmative; and

(d15) adding a new entry relating to the portable communication unit with an out mark in the database at the layer i node, and stopping the process for the layer i node, the out mark indicating that the portable communication unit is not at its home address.

23. The process of claim 22 further comprising the following step, after step (d2):

(d16) proceeding to step (d4) when the determination of step (d2) is negative.

24. The process of claim 23 further comprising the following step, after step (d12):

(d17) determining that an error has occurred when the determination of step (d12) is negative.

25. The process of claim 24 further comprising the following step, after step (d13):

(d18) proceeding to step (d15) when the determination of step (d13) is negative.

26. The process of claim 19 further comprising the following step, after step (d3):

(d19) stopping the process for layer i, when the determination of step (d3) is negative.