Dynamic user registration method in a mobile communications network

• US 5,519,706 A
• Filed: 06/28/1994
• Issued: 05/21/1996
• Est. Priority Date: 12/03/1993
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Bello, Eliane D., Krawczyk, Hugo, Bauchot, Frederic, Bantz, David, Kutten, Shay
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Ton, Dang
• Application Number:
  US08/267,689
• Time in Patent Office: 693 Days
• Field of Search: 370/60, 370/85.1, 370/85.2, 370/85.3, 370/85.7, 370/85.13, 370/94.1, 370/94.3, 370/95.1, 370/95.3, 370/85.6, 340/825.5, 340/825.51, 340/825.02, 340/825.03, 455/1, 455/33.1, 455/33.2, 455/53.1, 455/54.1, 455/54.2, 455/56.1
• US Class Current: 455/435.2
• CPC Class Codes: H04L 2209/80 Wireless network architectures or network communication protocols for wireless network security H04W12/00
• CPC Class Codes: H04L 9/0844 with user authentication or key authentication, e.g. ElGamal, MTI, MQV-Menezes-Qu-Vanstone protocol or Diffie-Hellman protocols using implicitly-certified keys
• CPC Class Codes: H04L 9/0891 Revocation or update of secret information, e.g. encryption key update or rekeying

Abstract

In a communications system comprising a number of base stations, each base station communicating over a shared communication channel with a plurality of registered stations and controlling the network cell formed by said plurality of registered stations, a method is described for dynamically registering and deregistering mobile stations. Each station owns a unique address and is allocated a local identifier at registration time. Each network cell owns a unique cell identifier known to all registered stations belonging to this network cell. Base stations manage cell members data uniquely associating the unique address and the local identifier corresponding to each one of the mobile stations belonging to their network cell. A registration request is sent to a selected base station by a registering mobile station, comprising the unique cell identifier of the network cell controlled by the selected base station and the unique address of the registering mobile station; the selected base station detects in its cell members data any conflicting registered station whose unique address matches the unique address of the registering mobile station and sends an address check packet to any conflicting registered station, comprising the unique address of the conflicting registered station, its local identifier and the identifier of the network cell it controls. A receiving registered mobile station sends to the selected base station, an acknowledgement to the address check packet if its unique address, the local identifier of its owning base station and its network cell identifier all match with the ones carried by the address check packet. The selected base station rejects the registration request it it receives an acknowledgement to its address check packet. The same address check packet is used to deregister inactive stations.

Claims

1. A method for dynamically registering a new station in a communications system comprising a number of base stations, each base station communicating over a shared communication channel with a plurality of registered stations and controlling a network cell formed by said plurality of registered stations, wherein:

each registered station owns a unique address and is allocated a local identifier,

each network cell owns a unique cell identifier known to all registered stations belonging to said each network cell,

said each base station manages cell members data uniquely associating the unique address and the local identifier corresponding to each one of said plurality of registered stations;

said method comprising the steps of;

a. send a registration request from said registering new station to a selected base station, said registration request comprising the unique cell identifier of the network cell controlled by said selected base station and the unique address of said registering new station;

b. upon reception of said registration request at said selected base station, detect in said cell members data any conflicting registered station whose said unique address matches the unique address of said registering new station;

1) if no conflicting registered station is detected, accept said registration request, allocate a local identifier to said registering new station and add an entry to said cell members data uniquely associating the unique address and the local identifier of said registering new station;

2) if a conflicting registered station is detected, send an address check packet from said selected base station to said conflicting registered station, said address check packet comprising in a first field the unique address of said conflicting registered station, in a second field the local identifier of said conflicting registered station and in a third field the identifier of the network cell controlled by said selected base station;

c. upon reception of said address check packet at a receiving registered station;

1) compare said first, second and third fields respectively with the unique address, the local identifier and the network cell identifier of said receiving registered station; and

2) if all of said first, second and third fields match, send an acknowledgement to said address check packet, from said receiving registered station to said selected base station.

d. reject said registration request upon reception at said selected base station of an acknowledgement to said address check packet from said receiving registered station.

2. The method of claim 1, wherein step c. further comprises deregistering said receiving registered station from said communication system if said first field does not match and said second and third fields match.

3. The method of claim 1, wherein step c. further comprises ignoring said address check packet if said first field matches and either said second field or said third field does not match.

4. A method for dynamically deregistering inactive stations in a communications system comprising a number of base stations, each base station communicating over a shared communication channel with a plurality of registered stations and controlling a network cell formed by said plurality of registered stations, wherein:

each registered station owns a unique address and is allocated a local identifier,

each network cell owns a unique cell identifier known to all registered stations belonging to said each network cell,

said each base station manages cell members data uniquely associating the unique address and the local identifier corresponding to each one of said plurality of registered stations;

said method comprising the steps of;

a. detect inactive registered stations;

b. send an address check packet from the base station controlling the network cell of said inactive registered stations, said address check packet comprising in a first field the unique address of said inactive registered station, in a second field the local identifier of said inactive registered station and in a third field the identifier of the network cell of said inactive registered station;

c. upon reception of said address check packet at a receiving registered station;

1) compare said first, second and third fields respectively with the unique address, the local identifier and the network cell identifier of said receiving registered station;

2) if all of said first, second and third fields match, send an acknowledgement to said address check packet, from said receiving registered station to said base station; and

3) if either of said first, second or third field does not match, ignore said address check packet.

d. deregister said inactive registered station if said owner base stations does not receive any acknowledgement to said address check packet after a number of retries.

5. The method of claim 4, wherein step d. comprises deletion by owner base station of the unique address and the local identifier corresponding to said inactive registered station in said cell members data.

6. A system for dynamically registering a new station in a communications system comprising a number of base stations, each base station communicating over a shared communication channel with a plurality of registered stations, each registered station being assigned a unique address, said plurality of registered stations designated as a network cell and being assigned a unique network cell identifier known to said base station and to said plurality of registered stations, wherein each base station manages said network cell members'"'"' data uniquely associating for each one of said plurality of registered stations said unique address with a local identifier, said system comprising:

a) means for selecting at said new station a base station as a selected base station and a network cell identifier as a selected network cell identifier;

b) means for sending a registration request from said new station to said selected base station, said registration request comprising said selected network cell identifier and a unique address assigned to said new station;

c) means for detecting in said network cell members'"'"' data, upon reception of said registration request at said selected base station, any conflicting registered station whose unique address matches said new station'"'"'s unique address;

d) means for accepting said registration request when no conflicting registered station is found;

e) means for sending an address check packet from said selected base station to each conflicting registered station, said address check packet comprising in a first field the unique address of each conflicting registered station, in a second field the local identifier of each conflicting registered station and in a third field the network cell identifier of said selected base station;

f) means responsive to receiving said address check packet at said conflicting registered station, comparing said first, second and third fields of said address check packet respectively with the unique address, the local identifier and the network cell identifier of said conflicting registered station and said comparing means sending an acknowledgement of said address check packet from said conflicting registered station to said selected base station if all fields match; and

g) means for rejecting said registration request sent by said new station upon receipt at said selected base station of an acknowledgement to said address check packet from one of said conflicting registered stations;

whereby said new station is registered when no conflicting registered station is detected, or when no acknowledgement is received at said selected base station in response to said address check packet, and whereby said registration request is rejected when acknowledgement of said address check packet is sent by said conflicting registered station and received at said selected base station.

7. The system as defined in claim 6, wherein means for receiving said address check packet further comprises means for de-registering said conflicting registered station from said communications system if said first field does not match and both said second and third fields match.

8. The system as defined in claim 6 wherein means responsive to said address check packet further comprises means for ignoring said address check packet if said first field matches and either said second field or said third field does not match.

11. A system as defined in claim 6, wherein said shared communication channel is a radio frequency communication channel.

12. A system as defined in claim 6, wherein said shared communication channel is an infrared communication channel.

9. A system for dynamically deregistering inactive stations in a communications system comprising a number of base stations, each base station communicating over a shared communication channel with a plurality of registered stations, each registered station being assigned a unique address, said plurality of registered stations, designated as a network cell, being assigned a unique network cell identifier known to said base station and to said plurality of registered stations, wherein each base station manages network cell members'"'"' data uniquely associating for each one of said plurality of registered stations said unique address with a local identifier, said system comprising:

means for detecting at one of said base stations an inactive registered station among said plurality of registered stations;

means for sending an address check packet from said base station detecting said inactive registered station to said inactive registered station, said address check packet comprising in a first field the unique address of said inactive registered station, in a second field the local identifier of said inactive registered station and in a third field the network cell identifier of said base station detecting said inactive registered station;

means responsive to said address check packet at said inactive registered station, comparing said first, second and third fields of said address check packet respectively with the unique address, the local identifier and the network cell identifier of said inactive registered station and said comparing means sending an acknowledgement of said address check packet from said inactive registered station to said base station detecting said inactive registered station if all fields match; and

means for deregistering said inactive registered station if said base station .detecting said inactive registered station does not receive said acknowledgement after a number of said address check packet retries.

10. The system as defined in claim 9 wherein the means for deregistering said inactive registered station further comprises:

means responsive to said base station detecting said inactive registered station for deleting the unique address and the local identifier corresponding to said inactive registered station in said network cell members'"'"' data.

13. A method for dynamically registering a new station in a communications system comprising a number of base stations, each base station communicating over a shared communication channel with a plurality of registered stations, each registered station being assigned a unique address, said plurality of registered stations designated as a network cell and being assigned a unique network cell identifier known to said base station and to said plurality of registered stations, wherein each said base station manages network cell members'"'"' data uniquely associating for each one of said plurality of registered stations said unique address with a local identifier, said method comprising the steps of:

a) selecting at said new station a base station as a selected base station and a selected network cell identifier as a selected network cell identifier;

b) sending a registration request from said new station to said selected base station, said registration request comprising said selected network cell identifier and a unique address assigned to said new station;

c) upon reception of said registration request at said selected base station, detecting in said network cell members'"'"' data any conflicting registered station whose unique address matches said new station'"'"'s unique address; and

d) accepting said registration request when no conflicting registered station is found;

e) determining if said conflicting registered station is in said network cell; and

f) rejecting said registration request sent by said new station upon determination that said conflicting registered station is in said network, cell;

whereby said new station is registered when no conflicting registered station is detected, and whereby said registration request is rejected when a conflicting registered station is determined to be in said network cell.

14. The method of claim 13 wherein the determining step further includes the steps of:

g) sending an address check packet from said selected base station to each conflicting registered station, said address check packet comprising in a first field the unique address of said each conflicting registered station, in a second field the local identifier of said each conflicting registered station and in a third field the network cell identifier of said selected base station;

h) receiving said address check packet at said conflicting registered stations, comparing said first, second and third fields of said address check packet respectively with the unique address, the local identifier and the network cell identifier of the conflicting registered station and sending an acknowledgement of said address check packet from said conflicting registered station to said selected base station if all fields match; and

wherein the rejecting step further includes the step of;

i) rejecting said registration request sent by said new station upon receipt at said selected base station of an acknowledgement to said address Check packet from one of said conflicting registered stations.

15. The method of claim 14 wherein step h) further comprises deregistering said conflicting registered station from said communications system if said first field does not match and both said second and third fields match.

16. The method of claim 14 wherein step h) further comprises ignoring said address check packet if said first field matches and either said second field or said third field does not match.

17. A method for dynamically deregistering inactive stations in a communications system comprising a number of base stations, each base station communicating over a shared communication channel with a plurality of registered stations, each registered station being assigned a unique address, said plurality of registered stations, designated as a network cell, being assigned a unique network cell identifier known to said base station and to said plurality of registered stations, wherein each base station manages network cell members data uniquely associating for each one of said plurality of registered stations said unique address with a local identifier, said method comprising the steps of:

a) detecting at one of said base stations an inactive registered station among said plurality of registered stations;

b) sending an address check packet from said base station detecting said inactive registered station to said inactive registered station, said address check packet comprising in a first field the unique address of said inactive registered station, in a second field the local identifier of said inactive registered station and in a third field the network cell identifier of said base station detecting said inactive registered station;

c) receiving said address check packet at said inactive registered station, comparing said first, second and third fields of said address check packet respectively with the unique address, the local identifier and the network cell identifier of said inactive registered station and sending an acknowledgement to said address check packet from said inactive registered station to said base station detecting said inactive registered station if all fields match; and

d) deregistering said inactive registered station if said detecting base station does not receive said acknowledgement after a number of said address check message retries.

18. The method of claim 17 wherein step d) comprises deletion by said base station detecting said inactive registered station of the unique address and the local identifier corresponding to said inactive registered station in said network cell members'"'"' data.