Mobile telephone system call processing arrangement

• US 5,278,892 A
• Filed: 01/21/1993
• Issued: 01/11/1994
• Est. Priority Date: 07/09/1991
• Status: Expired due to Term

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: AT&T, Inc.
• Inventors: Smolik, Kenneth F., Roberts, LaJeana N., Bolliger, Brian D., Strom, Kenneth W., Bursh, Talmage P. Jr., Spencer, Douglas A., Thompson, John S., Mulberg, Alan S., Ho, Kelvin K.
• Primary Examiner(s): Ng, Jin F.
• Assistant Examiner(s): CUMMING, WILLIAM D
• Application Number:
  US08/007,034
• Time in Patent Office: 355 Days
• Field of Search: 379/56, 379/58, 379/59, 379/60, 379/229, 455/31.1, 455/33.1, 455/34.1, 370/94.1, 370/100.1
• US Class Current: 455/442
• CPC Class Codes: H04W 36/18 for allowing seamless reselection, e.g. soft reselection
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support

Abstract

A CDMA cellular radio-telephone system (FIG. 2) comprises a packet-switched communications network (202, 207, 201) that interconnects cells (base stations; 202) with each other and with the public telephone network (100). A unique combination of a static addressing plan that uses a different LAPD DLCI (302 in FIG. 7) for each unidirectional virtual call path, direct cell (202)-to-cell and cell-to-call-processing unit (264 in FIG. 5) control information exchanges, and packet-switching techniques that permit call traffic and control communications to share call paths and permit different call paths to share physical resources, is applied to call processing. This enables soft handoffs (FIGS. 27-29) to be handled in a manner transparent to the parties to the call and without significant involvement of system control elements (134 and 261 in FIG. 2) whose involvement would adversely impact the system'"'"'s call-handling capacity. It also enables soft handoffs to occur without change of the call processing unit that is handling the call, so that a single call processing unit continues to handle the call from start to finish through even multiple soft handoffs.

Claims

1. A method of handling a call of a mobile wireless-call user terminal that is moving from a vicinity of a first service node to a vicinity of a second service node in a wireless-access telecommunications system that includes the mobile wireless-call user terminal, a plurality of service nodes each for providing wireless-call services to wireless-call user terminals in its vicinity, and at least one interface node connected to the service nodes and having a plurality of call processing units each for interfacing a wireless call that extends between a user terminal and a service node to a telecommunications facility, the method comprising the steps of:

communicating call traffic of the call between the mobile user terminal and the first service node, and between one of the call processing units and a telecommunications facility;

communicating the call traffic of the call between the first service node and the one call processing unit across a packet-switched call path set up for the call on a communication channel between the first service node and the one call processing unit, using different fixed addresses for different endpoints of the call path to route the call traffic across the channel;

in response to detecting that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, sending notification thereof from the first service node to the second service node;

in response to receiving the notification at the second service node, setting up a packet-switched call path for the call on a communication channel between the second service node and the one call processing unit by communicating across the communication channel between the second service node and the one call processing unit;

communicating duplicate call traffic of the call between the mobile user terminal and the first and the second service nodes;

communicating the duplicate call traffic of the call between the first and the second service nodes and the one call processing unit across the packet-switched call paths set up for the call on the communication channels between the first and the second service nodes and the one call processing unit, using different fixed addresses for different endpoints of every call path to route the duplicate call traffic across the channels; and

communicating a single copy of the duplicate call traffic of the call between the one call processing unit and the telecommunications facility by duplicating the call traffic outgoing to the service nodes and discarding a duplicate of the call traffic incoming from the service nodes.

2. The method of claim 1 wherein

each step of communicating call traffic of the call between a service node and a call processing unit comprises the step of:

frame-relaying packets containing the call traffic between the service node and the call processing unit.

3. The method of claim 1 wherein:

each said different fixed address of a call-path endpoint located at a service node identifies a wireless channel of the service node which corresponds to the call.

4. The method of claim 3 wherein:

each said different fixed address of a call-path endpoint located at the one call processing unit identifies a different logical port of the one call processing unit.

5. The method of claim 1 wherein:

each said different fixed address of a call-path endpoint comprises a unique Data Link Connection Identifier (DLCI) of Link Access Protocol-D Channel (LAPD) packets carrying the call traffic of the call.

6. The method of claim 1 in a wireless-access telecommunications system that further includes a controller for assigning call processing units to handle calls, including assigning the one of the call processing units to handle said call, wherein:

the step of communicating call traffic of the call between the mobile user terminal and the first service node comprises the step of

communicating call traffic of the call between the mobile user terminal and the first service node, and between one of the call processing units and a telecommunications facility, without involvement therein of the controller;

the step of communicating the call traffic of the call between the first service node and the one call processing unit comprises the step of

communicating the call traffic of the call between the first service node and the one call processing unit without involvement therein of the controller, across a packet-switched call path set up for the call on a communication channel between the first service node and the one call processing unit, using different fixed addresses for different endpoints of the call path to route the call traffic across the channel;

the step of sending notification comprises the step of

in response to detecting that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, sending notification thereof from the first service node to the second service node without involvement therein of the controller;

the step of setting up a packet-switched call path comprises the step of

in response to receiving the notification at the second service node, setting up a packet-switched call path for the call on a communication channel between the second service node and the one call processing unit without involvement therein of the controller by communicating across the communication channel between the second service node and the one call processing unit;

the step of communicating duplicate call traffic of the call between the mobile user terminal and the service nodes comprises the step of

communicating duplicate call traffic of the call between the mobile user terminal and the first and the second service nodes without involvement therein of the controller;

the step of communicating the duplicate call traffic of the call between the service nodes and the one call processing unit comprises the step of

communicating the duplicate call traffic of the call between the first and the second service nodes and the one call processing unit without involvement therein of the controller, across the packet-switched call paths set up for the call on the communication channels between the first and the second service nodes and the one call processing unit, using different fixed addresses for different endpoints of every call path to route the duplicate call traffic across the channels; and

the step of communicating a single copy of the duplicate call traffic comprises the step of

communicating a single copy of the duplicate call traffic of the call between the one call processing unit and the telecommunications facility without involvement therein of the controller, by duplicating the call traffic outgoing to the service nodes and discarding a duplicate of the call traffic incoming from the service nodes.

7. The method of claim 1 in a wireless-access telecommunications system that further includes a system controller for coordinating call-establishment operations of the service nodes and the interface node, including coordinating call establishment operations of the first service node and the interface node for said call, wherein:

the step of communicating call traffic of the call between the mobile user terminal and the first service node comprises the step of

communicating call traffic of the call between the mobile user terminal and the first service node, and between one of the call processing units and a telecommunications facility, without involvement therein of the controller;

the step of communicating the call traffic of the call between the first service node and the one call processing unit comprises the step of

communicating the call traffic of the call between the first service node and the one call processing unit without involvement therein of the controller, across a packet-switched call path set up for the call on a communication channel between the first service node and the one call processing unit, using different fixed addresses for different endpoints of the call path to route the call traffic across the channel;

the step of sending notification comprises the step of

in response to detecting that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, sending notification thereof from the first service node to the second service node without involvement therein of the controller;

the step of setting up a packet-switched call path comprises the step of

in response to receiving the notification at the second service node, setting up a packet-switched call path for the call on a communication channel between the second service node and the one call processing unit without involvement therein of the controller by communicating across the communication channel between the second service node and the one call processing unit;

the step of communicating duplicate call traffic of the call between the mobile user terminal and the service nodes comprises the step of

communicating duplicating call traffic of the call between the mobile user terminal and the first and the second service nodes without involvement therein of the controller;

the step of communicating the duplicate call traffic of the call between the service nodes and the one call processing unit comprises the step of

communicating the duplicate call traffic of the call between the first and the second service nodes and the one call processing unit without involvement therein of the controller, across the packet-switched call paths set up for the call on the communication channels between the first and the second service nodes and the one call processing unit, using different fixed addresses for different endpoints of every call path to route the duplicate call traffic across the channels; and

the step of communicating a single copy of the duplicate call traffic comprises the step of

communicating a single copy of the duplicate call traffic of the call between the one call processing unit and the telecommunications facility without involvement therein of the controller, by duplicating the call traffic outgoing to the service nodes and discarding a duplicate of the call traffic incoming from the service nodes.

8. The method of claim 1 in a wireless-access telecommunications system that further includes an interface node controller for assigning call processing units to handle calls, including assigning the one of the call processing units to handle said call, and a supervisory controller for coordinating call-establishment operations of the service nodes and the interface node, including coordinating call-establishment operations of the first service node and the interface node for said call, wherein:

the step of communicating call traffic of the call between the mobile user terminal and the first service node comprises the step of

communicating call traffic of the call between the mobile user terminal and the first service node, and between one of the call processing units and a telecommunications facility, without involvement therein of the controllers;

the step of communicating the call traffic of the call between the first service node and the one call processing unit comprises the step of

communicating the call traffic of the call between the first service node and the one call processing unit without involvement therein of the controllers, across a packet-switched call path set up for the call on a communication channel between the first service node and the one call processing unit, using different fixed addresses for different endpoints of the call path to route the call traffic across the channel;

the step of sending notification comprises the step of

in response to detecting that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, sending notification thereof from the first service node to the second service node without involvement therein of the controller;

the step of setting up a packet-switched call path comprises the step of

in response to receiving the notification at the second service node, setting up a packet-switched call path for the call on a communication channel between the second service node and the one call processing unit without involvement therein of the controllers by communicating across the communication channel between the second service node and the one call processing unit;

the step of communicating duplicate call traffic of the call between the mobile user terminal and the service nodes comprises the step of

communicating duplicate call traffic of the call between the mobile user terminal and the first and the second service nodes without involvement therein of the controllers;

the step of communicating the duplicate call traffic of the call between the service nodes and the one call processing unit comprises the step of

communicating the duplicate call traffic of the call between the first and the second service nodes and the one call processing unit without involvement therein of the controllers, across the packet-switched call paths set up for the call on the communication channels between the first and the second service nodes and the one call processing unit, using different fixed addresses for different endpoints of every call path to route the duplicate call traffic across the channels; and

the step of communicating a single copy of the duplicate call traffic comprises the step of

communicating a single copy of the duplicate call traffic of the call between the one call processing unit and the telecommunications facility without involvement therein of the controllers, by duplicating the call traffic outgoing to the service nodes and discarding a duplicate of the call traffic incoming from the service nodes.

9. The method of claim 8 wherein

the recited steps are preceded by the further steps of:

detecting an origination of the call;

in response to the detection of the origination, notifying thereof the supervisory controller;

in response to the notification, sending a first message from the supervisory controller to the first service node to establish a call path for the call between the first service node and the one call processing unit;

in response to the notification, sending a second message from the supervisory controller to the interface node controller to establish a call connection for the call between the one call processing unit and the telecommunications facility;

in response to receiving the second message at the interface node controller, establishing a call connection for the call between the one call processing unit and the telecommunications facility by action of the interface node controller; and

in response to receiving the first message at the first service node, setting up the packet-switched call path for the call on the communication channel between the first service node and the one call processing unit by communicating across the communication channel between the first service node and the one call processing unit.

10. The method of claim 1 further comprising the steps of:

in response to detecting that the mobile user terminal is moving from a vicinity of both the first and the second service nodes to the vicinity of only an individual one of the first and the second service nodes, sending notification thereof from a detecting one of the first and the second service nodes to another one of the first and the second service nodes to indicate transfer of responsibility for the call to solely the individual one of the first and the second service nodes;

in response to the detecting, ceasing to communicate call traffic of the call from the other than the individual one of the first and the second service nodes;

in response to the detecting, communicating a notification thereof from the other than the individual one of the first and the second service nodes to the one call processing unit across the communication channel between the other than the individual one of the first and the second service nodes and the one call processing unit; and

in response to receiving the notification at the one call processing unit, ceasing to communicate call traffic of the call from the one call processing unit to the other than the individual one of the first and the second service nodes.

11. A method of handling a call of a mobile wireless-call user terminal that is moving from a vicinity of a first service node to a vicinity of a second service node in a wireless-access telecommunications system that includes the mobile wireless-call user terminal, a plurality of service nodes each for providing wireless-call services to wireless-call user terminals in its vicinity, and at least one interface node connected to the service nodes and having a plurality of call processing units each for interfacing a wireless call that extends between a user terminal and a service node to a telecommunications facility, the method comprising the steps of:

in response to receiving incoming call traffic of the call from the mobile user terminal at the first service node, sending first packets containing the received incoming call traffic and each having a first address which identifies the call'"'"'s corresponding one of the call processing units, from the first service node to the interface node;

in response to receiving the first packets at the one call processing unit, sending the incoming call traffic contained in the first packets from the one call processing unit to a telecommunications facility;

in response to receiving outgoing call traffic of the call from the telecommunications facility at the one call processing unit, sending second packets containing the received outgoing call traffic and each having a second address different from the first address and which identifies the first service node, from the one call processing unit to the first service node;

in response to receiving the second packets at the first service node, sending the outgoing call traffic contained in the second packets from the first service node to the mobile user terminal;

detecting that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

in response to the detecting, sending a message specifying a third address different from the first address and which also identifies the one call processing unit, from the first service node to the second service node;

in response to receiving the message at the second service node, sending a third packet both (a) specifying a fourth address different from the second and the third addresses and which identifies the second service node and (b) having the third address, from the second service node to the interface node;

in response to receiving incoming call traffic of the call from the mobile user terminal at the second service node subsequently to receiving the message, sending fourth packets containing the received incoming call traffic and each having the third address, from the second service node to the interface node;

in response to receiving the third packet at the one call processing unit, storing the fourth address for use in the call by the one call processing unit;

in response to receiving outgoing call traffic of the call from the telecommunications facility subsequently to receiving the third packet, sending the second packets from the one call processing unit to the first service node and sending fifth packets containing same received outgoing call traffic as the second packets and each having the fourth address, from the one call processing unit to the second service node;

in response to receiving the fifth packets at the second service node, sending the outgoing call traffic contained in the fifth packets from the second service node to the mobile user terminal; and

in response to receiving the first packets and the fourth packets both containing same received incoming call traffic at the one call processing unit subsequently to receiving the third packet, selecting the incoming call traffic contained by one of the received first and fourth packets that contain the same traffic, and sending only the selected incoming call traffic to the telecommunications facility.

12. The method of claim 11 wherein

the step of sending the outgoing call traffic contained in the fifth packets comprises the step of:

in response to receiving the second packets at the first service node and receiving the fifth packets at the second service node, simultaneously sending the same outgoing call traffic contained in the received second and the received fifth packets from each receiving service node to the mobile user terminal.

13. The method of claim 11 wherein

each step of sending a packet comprises the step of:

frame-relaying the packet.

14. The method of claim 11 in a wireless-access telecommunications system wherein the interface node is connected to the service nodes by a plurality of telecommunications links, wherein:

the third and the fourth packets are sent from the second service node to the interface node and are received by the one call processing unit on a same one of the links.

15. The method of claim 11 wherein:

the second address identifies a wireless channel of the first service node which corresponds to the call; and

the fourth address identifies a wireless channel of the second service node which corresponds to the call.

16. The method of claim 15 wherein:

the first and the third addresses identify different logical ports of the one call processing unit.

17. The method of claim 11 wherein:

each packet comprises a Link Access Protocol-D Channel (LAPD) packet; and

each different address comprises a unique Data Link Connection Identifier (DLCI).

18. The method of claim 11 in a wireless-access telecommunications system that further includes a controller for assigning individual call processing units to handle individual calls, including assigning the one call processing unit to handle said call, wherein:

the step of sending first packets comprises the step of

in response to receiving incoming call traffic of the call from the mobile user terminal at the first service node, sending first packets containing the received incoming call traffic and each having a first address which identifies the call'"'"'s corresponding one of the call processing units, from the first service node to the interface node without involvement therein of the controller,

the step of sending the incoming call traffic comprises the step of

in response to receiving the first packets at the one call processing unit, sending the incoming call traffic contained in the first packets from the one call processing unit to a telecommunications facility without involvement therein of the controller;

the step of sending second packets comprises the step of

in response to receiving outgoing call traffic of the call from the telecommunications facility at the one call processing unit, sending second packets containing the received outgoing call traffic and each having a second address different from the first address and which identifies the first service node, from the one call processing unit to the first service node without involvement therein of the controller;

the step of sending the outgoing call traffic, contained in the second packets, comprises the step of

in response to receiving the second packets at the first service node, sending the outgoing call traffic contained in the second packets from the first service node to the mobile user terminal without involvement therein of the controller;

the step of detecting comprises the step of

detecting, without involvement therein of the controller, that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the step of sending a message comprises the step of

in response to the detecting, sending a message specifying a third address different from the first address and which also identifies the one call processing unit, from the first service node to the second service node without involvement therein of the controller;

the step of sending a third packet comprises the step of

in response to receiving the message at the second service node, sending a third packet both (a) specifying a fourth address different from the second and the third addresses and which identifies the second service node and (b) having the third address, from the second service node to the interface node without involvement therein of the controller;

the step of sending fourth packets comprises the step of

in response to receiving incoming call traffic of the call from the mobile user terminal at the second service node subsequently to receiving the message, sending fourth packets containing the received incoming call traffic and each having the third address, from the second service node to the interface node without involvement therein of the controller;

the step of storing the fourth address comprises the step of

in response to receiving the third packet at the one call processing unit, storing the fourth address, without involvement therein of the controller, for use in the call by the one call processing unit;

the step of sending the second packets and sending fifth packets comprises the step of

in response to receiving outgoing call traffic of the call from the telecommunications facility subsequently to receiving the third packet, sending the second packets from the one call processing unit to the first service node without involvement therein of the controller and sending fifth packets containing same received outgoing call traffic as the second packets and each having the fourth address, from the one call processing unit to the second service node without involvement therein of the controller;

the step of sending the outgoing call traffic contained in the fifth packet comprises the step of

in response to receiving the fifth packets at the second service node, sending the outgoing call traffic contained in the fifth packets from the second service node to the mobile user terminal without involvement therein of the controller; and

the step of selecting comprises the step of

in response to receiving the first packets and the fourth packets both containing same received incoming call traffic at the one call processing unit subsequently to receiving the third packet, selecting the incoming call traffic contained by one of the received first and fourth packets that contain the same traffic and sending only the selected incoming call traffic to the telecommunications facility without involvement therein of the controller.

19. The method of claim 11 in a wireless-access telecommunications system that further includes a system controller for coordinating call-establishment operations of the service nodes and the interface node, including coordinating call-establishment operations of the first service node and the interface node for said call, wherein:

the step of sending first packets comprises the step of

in response to receiving incoming call traffic of the call from the mobile user terminal at the first service node, sending first packets containing the received incoming call traffic and each having a first address which identifies the call'"'"'s corresponding one of the call processing units, from the first service node to the interface node without involvement therein of the controller;

the step of sending the incoming call traffic comprises the step of

in response to receiving the first packets at the one call processing unit, sending the incoming call traffic contained in the first packets from the one call processing unit to a telecommunications facility without involvement therein of the controller;

the step of sending second packets comprises the step of

in response to receiving outgoing call traffic of the call from the telecommunications facility at the one call processing unit, sending second packets containing the received outgoing call traffic and each having a second address different from the first address and which identifies the first service node, from the one call processing unit to the first service node without involvement therein of the controller;

the step of sending the outgoing call traffic, contained in the second packets, comprises the step of

in response to receiving the second packets at the first service node, sending the outgoing call traffic contained in the second packets from the first service node to the mobile user terminal without involvement therein of the controller;

the step of detecting comprises the step of

detecting, without involvement therein of the controller, that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the step of sending a message comprises the step of

in response to the detecting, sending a message specifying a third address different from the first address and which also identifies the one call processing unit, from the first service node to the second service node without involvement therein of the controller,

the step of sending a third packet comprises the step of

in response to receiving the message at the second service node, sending a third packet both (a) specifying a fourth address different from the second and the third addresses and which identifies the second service node and (b) having the third address, from the second service node to the interface node without involvement therein of the controller;

the step of sending fourth packets comprises the step of

in response to receiving incoming call traffic of the call from the mobile user terminal at the second service node subsequently to receiving the message, sending fourth packets containing the received incoming call traffic and each having the third address, from the second service node to the interface node without involvement therein of the controller;

the step of storing the fourth address comprises the step of

in response to receiving the third packet at the one call processing unit, storing the fourth address, without involvement therein of the controller, for use in the call by the one call processing unit;

the step of sending the second packets and sending fifth packets comprises the step of

in response to receiving outgoing call traffic of the call from the telecommunications facility subsequently to receiving the third packet, sending the second packets from the one call processing unit to the first service node without involvement therein of the controller and sending fifth packets containing same received outgoing call traffic as the second packets and each having the fourth address, from the one call processing unit to the second service node without involvement therein of the controller;

the step of sending the outgoing call traffic contained in the fifth packets comprises the step of

in response to receiving the fifth packets at the second service node, sending the outgoing call traffic contained in the fifth packets from the second service node to the mobile user terminal without involvement therein of the controller; and

the step of selecting comprises the step of

in response to receiving the first packets and the fourth packets both containing same received incoming call traffic at the one call processing unit subsequently to receiving the third packet, selecting the incoming call traffic contained by one of the received first and fourth packets that contain the same traffic, and sending only the selected incoming call traffic to the telecommunications facility without involvement therein of the controller.

20. The method of claim 11 in a wireless-access telecommunications system that further includes an interface node controller for assigning individual call processing units to handle individual calls, including assigning the one of the call processing units to handle said call, and a supervisory controller for coordinating call-establishment operations of the service nodes and the interface node, including coordinating call-establishment operations of the first service node and the interface node for said call, wherein:

the step of sending first packets comprises the step of

in response to receiving incoming call traffic of the call from the mobile user terminal at the first service node, sending first packets containing the received incoming call traffic and each having a first address which identifies the call'"'"'s corresponding one of the call processing units, from the first service node to the interface node without involvement therein of the controllers;

the step of sending the incoming call traffic comprises the step of

in response to receiving the first packets at the one call processing unit, sending the incoming call traffic contained in the first packets from the one call processing unit to a telecommunications facility without involvement therein of the controllers;

the step of sending second packets comprises the step of

in response to receiving outgoing call traffic of the call from the telecommunications facility at the one call processing unit, sending second packets containing the received outgoing call traffic and each having a second address different from the first address and which identifies the first service node, from the one call processing unit to the first service node without involvement therein of the controllers;

the step of sending the outgoing call traffic, contained in the second packets, comprises the step of

in response to receiving the second packets at the first service node, sending the outgoing call traffic contained in the second packets from the first service node to the mobile user terminal without involvement therein of the controllers;

the step of detecting comprises the step of

detecting, without involvement therein of the controllers, that the mobile user terminal is moving from the vicinity of the first service node to the vicinity the second service node;

the step of sending a message comprises the step of

in response to the detecting, sending a message specifying a third address different from the first address and which also identifies the one call processing unit, from the first service node to the second service node without involvement therein of the controllers;

the step of sending a third packet comprises the step of

in response to receiving the message at the second service node, sending a third packet both (a) specifying a fourth address different from the second and the third addresses and which identifies the second service node and (b) having the third address, from the second service node to the interface node without involvement therein of the controllers;

the step of sending fourth packets comprises the step of

in response to receiving incoming call traffic of the call from the mobile user terminal at the second service node subsequently to receiving the message, sending fourth packets containing the received incoming call traffic and each having the third address, from the second service node to the interface node without involvement therein of the controllers;

the step of storing the fourth address comprises the step of

in response to receiving the third packet at the one call processing unit, storing the fourth address, without involvement therein of the controllers, for use in the call by the one call processing unit;

the step of sending the second packets and sending fifth packets comprises the step of

in response to receiving outgoing call traffic of the call from the telecommunications facility subsequently to receiving the third packet, sending the second packets from the one call processing unit to the first service node without involvement therein of the controllers and sending fifth packets containing same received outgoing call traffic as the second packets and each having the fourth address, from the one call processing unit to the second service node without involvement therein of the controllers;

the step of sending the outgoing call traffic contained in the fifth packets comprises the step of

in response to receiving the fifth packets at the second service node, sending the outgoing call traffic contained in the fifth packets from the second service node to the mobile user terminal without involvement therein of the controllers; and

the step of selecting comprises the step of

in response to receiving the first packets and the further packets both containing same received incoming call traffic at the one call processing unit subsequently to receiving the third packet, selecting the incoming call traffic contained by one of the received first and fourth packets that contain the same traffic, and sending only the selected incoming call traffic to the telecommunications facility without involvement therein of the controllers.

21. The method of claim 20 wherein

the recited steps are preceded by the further steps of:

detecting an origination of the call;

in response to the detection of the origination, notifying thereof the supervisory controller;

in response to the notification, sending a second message from the supervisory controller to the first service node to establish a call connection for the call between the first service node and the one call processing unit;

in response to the notification, sending a third message from the supervisory controller to the interface node controller to establish a call connection for the call between the one call processing unit and the telecommunications facility;

in response to receiving the third message at the interface node controller, establishing a call connection for the call between the one call processing unit and the telecommunications facility by action of the interface node controller;

in response to receiving the second message at the first service node, sending a third packet both (a) specifying the second address and (b) having the first address, from the first service node to the interface node to establish a call connection for the call between the first service node and the one call processing unit; and

in response to receiving the third packet at the one call processing unit, storing the second address for use in the call by the one call processing unit.

22. The method of claim 21 wherein:

each packet comprises a Link Access Protocol-D Channel (LAPD) packet; and

each different address comprises a unique Data Link Connection Identifier (DLCI).

23. The method of claim 11 further comprising the steps of:

secondly detecting that the mobile user terminal is moving from a vicinity of both the first and the second service nodes to the vicinity of only an individual one of the first and the second service nodes;

in response to the secondly detecting, sending a message from a detecting one of the first and the second service nodes to another one of the first and the second service nodes indicating transfer of responsibility for the call to solely the individual one of the first and the second service nodes;

in response to the secondly detecting, ceasing to send call traffic of the call received at the other than the individual one of the first and the second service nodes from the other than the individual one of the first and the second service nodes;

in response to the secondly detecting, sending a sixth packet from the other than the individual one of the first and the second service nodes to the interface node indicating that said other than the individual one of the first and the second service nodes is ceasing to serve the call; and

in response to receiving the sixth packet at the one call processing unit, ceasing to send packets containing outgoing call traffic of the call received at the one call processing unit from the one call processing unit to said other than the individual one of the first and the second service nodes.

24. The method of claim 11 further comprising the steps of:

secondly detecting that the mobile user terminal has moved from the vicinity of the first node to the vicinity of the second service node;

in response to the secondly detecting, sending a second message from the first service node to the second service node to notify the second service node of transfer of responsibility for serving the call from the first service node to the second service node;

in response to the secondly detecting, ceasing to send from the first service node call traffic of the call received at the first service node;

in response to the secondly detecting, sending a sixth packet having the first address and indicating that the first service node is ceasing to serve the call, from the first service node to the interface node; and

in response to receiving the sixth packet at the one call processing unit, ceasing to send the second packets from the one call processing unit to the first service node.

25. The method of claim 24 wherein

the step of sending a sixth packet is preceded by the steps of:

in response to the secondly detecting, sending a seventh packet having the first address and indicating that the first service node is ceasing to serve the call, from the first service node to the interface node;

in response to receiving the seventh packet at the one call processing unit, simultaneously sending an eighth and a ninth packet respectively having the second and the fourth address and indicating that the first service node is ceasing to serve the call, from the one call processing unit respectively to the first and the second service nodes; and

in response to receiving the eighth packet at the first service node and receiving the ninth packet at the second service node, simultaneously sending an indication that the first service node is ceasing to serve the call, from both the first and the second service nodes to the mobile user terminal.

26. The method of claim 25 wherein:

each packet comprises a Link Access Protocol-D Channel (LAPD) packet; and

each different address comprises a unique Data Link Connection Identifier (DLCI).

27. The method of claim 11 further comprising the steps of:

secondly detecting that the mobile user terminal is returning from the vicinity of both the first and the second service nodes to the vicinity of the first service node;

in response to the secondly detecting, sending a second message from the first service node to the second service node to notify the second service node of return of responsibility for serving the call from both the first and the second service nodes to the first service node;

receiving the second message at the second service node;

in response to receiving the second message, ceasing to send from the second service node call traffic of the call received at the second service node;

in response to receiving the second message, sending a sixth packet having the third address and indicating that the second service node is ceasing to serve the call, from the second service node to the interface node; and

in response to receiving the sixth packet at the one call processing unit, ceasing to send fourth packets from the one call processing unit to the second service node.

28. The method of claim 27 wherein

the step of sending a sixth packet is preceded by the steps of:

in response to the secondly detecting, sending a seventh packet having the first address and indicating that the second service node is ceasing to serve the call, from the first service node to the interface node;

in response to receiving the seventh packet at the one call processing unit, simultaneously sending an eighth and a ninth packet respectively having the second and the fourth address and indicating that the second service node is ceasing to serve the call, from the one call processing unit respectively to the first and the second service nodes; and

in response to receiving the eighth packet at first service node and receiving the ninth packet at the second service node, simultaneously sending an indication that the second service node is ceasing to serve the call, from both the first and the second service nodes to the mobile user terminal.

29. The method of claim 28 wherein:

each packet comprises a Link Access Protocol-D Channel (LAPD) packet; and

each different address comprises a unique Data Link Connection Identifier (DLCI).

30. The method of claim 27 wherein

the step of sending a sixth packet is followed by the step of:

in response to receiving the second message, sending a third message from the second service node to the first service node indicating that the second service node has ceased to serve the call.

31. A method of handling a call of a mobile wireless-call user terminal that is moving from a vicinity of a first service node to a vicinity of a second service node at the first and the second service nodes of a wireless-access telecommunications system that includes the mobile wireless-call user terminal, a plurality of service nodes each for providing wireless-call services to wireless-call user terminals in its vicinity, and at least one interface node connected to the service nodes and having a plurality of call processing units each for interfacing a wireless call that extends between a user terminal and a service node to a telecommunications facility, the method comprising the steps of:

in response to receiving incoming call traffic of the call from the mobile user terminal at the first service node, sending first packets containing received incoming call traffic and each having a first address which identifies the call'"'"'s corresponding one of the call processing units, from the first service node to the interface node for receipt and transmission of the incoming call traffic by the one call processing unit to a telecommunications facility;

in response to receiving at the first service node second packets from the one call processing unit containing outgoing call traffic received by the one call processing unit from the telecommunications facility and each having a second address different from the first address and which identifies the first service node, sending the outgoing call traffic contained in the second packets from the first service node to the mobile user terminal;

in response to detection that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, sending a message specifying a third address different from the first address and which also identifies the one call processing unit, from the first service node to the second service node;

in response to receiving the message at the second service node, sending a third packet both (a) specifying a fourth address different from the second and the third addresses and which identifies the second service node and (b) having the third address, from the second service node to the interface node for use of the fourth address for the call by the one call processing unit;

in response to receiving incoming call traffic of the call from the mobile user terminal at the first and second service nodes subsequently to the second service node receiving the message, respectively sending the first and fourth packets containing the received incoming call traffic and each fourth packet having the third address, respectively from the first and the second service nodes to the interface node for receipt by the one call processing unit of same incoming call traffic from both the first and the second service nodes, selection by the one call processing unit of incoming call traffic received from one of the first and the second service nodes, and sending of only the selected incoming call traffic to the telecommunications facility; and

in response to receiving at the first and the second service nodes respectively the second and fifth packets from the one call processing unit containing same outgoing call traffic received by the one call processing unit from the telecommunications facility subsequently to the one call processing unit receiving the third packet and each fifth packet having the fourth address, sending the same outgoing call traffic contained in the second and the fifth packets respectively from the first and the second service nodes to the mobile user terminal.

32. A method of handling a call of a mobile wireless-call user terminal that is moving from a vicinity of a first service node to a vicinity of a second service node at a call processing unit of a wireless-access telecommunications system that includes the mobile wireless-call user terminal, a plurality of service nodes each for providing wireless-call services to wireless-call user terminals in its vicinity, and at least one interface node connected to the service nodes and having a plurality of call processing units each for interfacing a wireless call that extends between a user terminal and a service node to a telecommunications facility, the method comprising the steps of:

in response to receiving at one call processing unit from the first service node first packets containing incoming call traffic received by the first service node from the mobile user terminal and each having a first address which identifies the one call processing unit as the call'"'"'s corresponding one of the call processing units, sending the incoming call traffic contained in the first packets from the one call processing unit to a telecommunications facility;

in response to receiving outgoing call traffic of the call from the telecommunications facility at the one call processing unit, sending second packets containing the received outgoing call traffic and each having a second address different from the first address and which identifies the first service node, from the one call processing unit to the first service node for receipt and transmission of the outgoing call traffic contained in the second packets by the first service node to the mobile user terminal;

in response to receiving at the one call processing unit from the second service node a third packet specifying a fourth address different from the second address and which identifies the second service node and having a third address different from the first and the fourth addresses and which also identifies the one call processing unit, which third address was specified by a message sent by the first service node to the second service node in response to detection that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, storing the fourth address for use in the call by the one call processing unit;

in response to receiving at the one call processing unit from the first and the second service nodes respectively the first packets and fourth packets both containing same incoming call traffic received by respectively the first and the second service nodes and the fourth packets having the third address, subsequently to receiving the third packet, respectively selecting the incoming call traffic contained by one of the received first and fourth packets which contain the same traffic and sending only the selected incoming call traffic to the telecommunications facility; and

in response to receiving outgoing call traffic of the call from the telecommunications facility subsequently to receiving the third packet, sending the second packets from the one call processing unit to the first service node and sending fifth packets containing same received outgoing call traffic as the second packets and each having the fourth address, from the one call processing unit to the second service node, for transmission by both the first and the second service nodes of the same outgoing call traffic to the mobile user terminal.

33. In a wireless-access telecommunications system that includes at least one mobile wireless-call user terminal, a plurality of service nodes each for providing wireless-call services to wireless-call user terminals in its vicinity, and at least one interface node connected to the service nodes and having a plurality of call processing units each for interfacing a wireless call that extends between a user terminal and a service node to a telecommunications facility, the improvement comprising:

first means (243 and 245 of master

     202) for communicating call traffic of the call between a first service node (master

     202) and a mobile user terminal that is in the vicinity of the first service node;

second means (244 of master

     202) cooperative with the first means for communicating the call traffic of the call between the first service node and the call'"'"'s associated one of the call processing units across a packet-switched call path set up for the call on a communication channel between the first service node and the one of the call processing units, by using different fixed addresses for different endpoints of the call path to route the call traffic across the channel;

third means (612,

     608) cooperative with the second means for communicating the call traffic of the call between the one call processing unit and a telecommunications facility;

fourth means (241 of master

     202) in the first service node responsive to detecting that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of a second service node (slave

     202), for sending notification thereof to the second service node;

fifth means (241 of slave

     202) in a second service node responsive to receiving the notification, for setting up a packet-switched call path for the call on a communication channel between the second service node and the one call processing unit by communicating across the communication channel with the one call processing unit;

sixth means (243 and 245 of slave

     202) for communicating the call traffic of the call between the mobile user terminal moving into the vicinity of the second service node and the second service node, so that duplicate copies of the call traffic are communicated between the mobile user terminal when it is moving from the vicinity of the first service node to the vicinity of the second service node and the first and the second service nodes;

seventh means (244 of slave

     202) cooperative with the sixth means for communicating the call traffic of the call between the second service node and the one call processing unit across the packet-switched call path set up for the call on the communication channel between the second service node and the one call processing unit, by using different fixed addresses for different endpoints of every call path to route the call traffic across the channel, so that duplicate copies of the call traffic are communicated between the one call processing unit and the first and the second service nodes when the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node; and

eighth means (602) in the one call processing unit cooperative with the second, the third, and the seventh means, for duplicating the call traffic communicated from the telecommunications facility and outgoing to the service nodes and discarding a duplicate of the call traffic incoming from the service nodes and communicated to the telecommunications facility, so that only a single copy of the call traffic is communicated between the one call processing unit and the telecommunications facility when the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node.

34. The improvement of claim 33 wherein the second and the seventh means each include:

means for frame-relaying packets containing the call traffic between a service node and a call processing unit.

35. The improvement of claim 33 wherein:

each said different fixed address of a call path endpoint located at a service node identifies a wireless channel of the service node which corresponds to the call.

36. The improvement of claim 35 wherein:

each said different fixed address of a call path endpoint located at the one call processing unit identifies a different logical port of the one call processing unit.

37. The improvement of claim 33 wherein:

each said different fixed address of a call path endpoint comprises a unique Data Link Connection Identifier (DLCI) of Link Access Protocol-D Channel (LAPD) packets carrying the call traffic of the call.

38. The improvement of claim 33 in a wireless-access telecommunications system that further includes a controller for assigning call processing units to handle calls, including assigning the one of the call processing units to handle said call, wherein:

the first means comprise

means for communicating, without involvement therein of the controller, call traffic of the call between a first service node and a mobile user terminal that is in the vicinity of the first service node, while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the second means comprise

means cooperative with the first means for communicating, without involvement therein of the controller, the call traffic of the call between the first service node and the call'"'"'s associated one of the call processing units while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, across a packet-switched call path set up for the call on a communication channel between the first service node and the one of the call processing units, by using different fixed addresses for different endpoints of the call path to route the call traffic across the channel;

the third means comprise

means cooperative with the second means for communicating, without involvement therein of the controller, the call traffic of the call between the one call processing unit and a telecommunications facility while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the fourth means comprise

means in the first service node responsive to detecting that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, for sending notification thereof to the second service node without involvement therein of the controller;

the fifth means comprise

means in a second service node responsive to receiving the notification, for setting up a packet-switched call path for the call on a communication channel between the second service node and the one call processing unit by communicating, without involvement therein of the controller, across the communication channel with the one call processing unit while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the sixth means comprise

means for communicating, without involvement therein of the controller, the call traffic of the call between the second service node and the mobile user terminal moving into the vicinity of the second service node, so that duplicate copies of the call traffic are communicated between the first and the second service nodes and the mobile user terminal while it is moving from the vicinity of the first service node to the vicinity of the second service node;

the seventh means comprise

means cooperative with the sixth means for communicating, without involvement therein of the controller, the call traffic of the call between the second service node and the one call processing unit across the packet-switched call path set up for the call on the communication channel between the second service node and the one call processing unit, by using different fixed addresses for different endpoints of every call path to route the call traffic across the channel, so that duplicate copies of the call traffic are communicated between the one call processing unit and the first and the second service nodes while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node; and

the eighth means comprise

means in the one call processing unit cooperative with the second, the third, and the seventh means, for duplicating, without involvement therein of the controller, the call traffic communicated from the telecommunications facility and outgoing to the service nodes and discarding, without involvement therein of the controller, a duplicate of the call traffic incoming from the service nodes and communicated to the telecommunications facility, so that only a single copy of the call traffic is communicated between the one call processing unit and the telecommunications facility while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node.

39. The improvement of claim 33 in a wireless-access telecommunications system that further includes a system controller for coordinating call-establishment operations of the service nodes and the interface node, including coordinating call-establishment operations of the first service node and the interface node for said call, wherein:

the first means comprise

means for communicating, without involvement therein of the controller, call traffic of the call between a first service node and a mobile user terminal that is in the vicinity of the first service node, while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the second means comprise

means cooperative with the first means for communicating, without involvement therein of the controller, the call traffic of the call between the first service node and the call'"'"'s associated one of the call processing units while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, across a packet-switched call path set up for the call on a communication channel between the first service node and the one of the call processing units, by using different fixed addresses for different endpoints of the call path to route the call traffic across the channel;

the third means comprise

means cooperative with the second means for communicating, without involvement therein of the controller, the call traffic of the call between the one call processing unit and a telecommunications facility while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the fourth means comprise

means in the first service node responsive to detecting that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, for sending notification thereof to the second service node without involvement therein of the controller;

the fifth means comprise

means in a second service node responsive to receiving the notification, for setting up a packet-switched call path for the call on a communication channel between the second service node and the one call processing unit by communicating, without involvement therein of the controller, across the communication channel with the one call processing unit while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the sixth means comprise

means for communicating, without involvement therein of the controller, the call traffic of the call between the second service node and the mobile user terminal moving into the vicinity of the second service node, so that duplicate copies of the call traffic are communicated between the first and the second service nodes and the mobile user terminal while it is moving from the vicinity of the first service node to the vicinity of the second service node;

the seventh means comprise

means cooperative with the sixth means for communicating, without involvement therein of the controller, the call traffic of the call between the second service node and the one call processing unit across the packet-switched call path set up for the call on the communication channel between the second service node and the one call processing unit, by using different fixed addresses for different endpoints of every call path to route the call traffic across the channel, so that duplicate copies of the call traffic are communicated between the one call processing unit and the first and the second service nodes while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node; and

the eighth means comprise

means in the one call processing unit cooperative with the second, the third, and the seventh means, for duplicating, without involvement therein of the controller, the call traffic communicated from the telecommunications facility and outgoing to the service nodes and discarding, without involvement therein of the controller, a duplicated of the call traffic incoming from the service nodes and communicated to the telecommunications facility, so that only a single copy of the call traffic is communicated between the one call processing unit and the telecommunications facility while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node.

40. The improvement of claim 33 in a wireless-access telecommunications system that further includes an interface node controller for assigning call processing units to handle calls, including assigning the one of the call processing units to handle said call, and a supervisory controller for coordinating call-establishment operations of the service nodes and the interface node, including coordinating call-establishment operations of the first service node and the interface node for said call, wherein:

the first means comprise

means for communicating, without involvement therein of the controllers, call traffic of the call between a first service node and a mobile user terminal that is in the vicinity of the first service node, while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the second means comprise

means cooperative with the first means for communicating, without involvement therein of the controllers, the call traffic of the call between the first service node and the call'"'"'s associated one of the call processing units while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, across a packet-switched call path set up for the call on a communication channel between the first service node and the one of the call processing units, by using different fixed addresses for different endpoints of the call path to route the call traffic across the channel;

the third means comprise

means cooperative with the second means for communicating, without involvement therein of the controllers, the call traffic of the call between the one call processing unit and a telecommunications facility while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the fourth means comprise

means in the first service node responsive to detecting that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, for sending notification thereof to the second service node without involvement therein of the controllers;

the fifth means comprise

means in a second service node responsive to receiving the notification, for setting up a packet-switched call path for the call on a communication channel between the second service node and the one call processing unit by communicating, without involvement therein of the controllers, across the communication channel with the one call processing unit while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the sixth means comprise

means for communicating, without involvement therein of the controllers, the call traffic of the call between the second service node and the mobile user terminal moving into the vicinity of the second service node, so that duplicate copies of the call traffic are communicated between the first and the second service nodes and the mobile user terminal while it is moving from the vicinity of the first service node to the vicinity of the second service node;

the seventh means comprise

means cooperative with the sixth means for communicating, without involvement therein of the controllers, the call traffic of the call between the second service node and the one call processing unit across the packet-switched call path set up for the call on the communication channel between the second service node and the one call processing unit, by using different fixed addresses for different endpoints of every call path to route the call traffic across the channel, so that duplicate copies of the call traffic are communicated between the one call processing unit and the first and the second service nodes while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node; and

the eighth means comprise

means in the one call processing unit cooperative with the second, the third, and the seventh means, for duplicating, without involvement therein of the controllers, the call traffic communicated from the telecommunications facility and outgoing to the service nodes and discarding, without involvement therein of the controllers, a duplicate of the call traffic incoming from the service nodes and communicated to the telecommunications facility, so that only a single copy of the call traffic is communicated between the one call processing unit and the telecommunications facility while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node.

41. The improvement of claim 33 further comprising:

ninth means responsive to detection that the mobile user terminal is moving from a vicinity of both the first and the second service nodes to the vicinity of only the second service node, for sending notification thereof from a detecting one of the first and the second service nodes to another one of the first and the second service nodes to indicate transfer of responsibility for the call to solely the second service node;

wherein

the first means are responsive to the detection by ceasing to communicate call traffic of the call between the first service node and the mobile user terminal;

the second means are responsive to the detection by ceasing to communicate call traffic of the call between the first service node and the one call processing unit and by communicating a notification thereof to the one call processing unit across the communication channel between the first service node and the one call processing unit; and

the eighth means are responsive to receipt of the notification from the second means by ceasing to duplicate and to discard the call traffic.

42. The improvement of claim 33 further comprising:

ninth means responsive to detection that the mobile user terminal is returning from a vicinity of both the first and the second service nodes to the vicinity of only the first service node, for sending notification thereof from a detecting one of the first and the second service nodes to another one of the first and the second service nodes to indicate transfer of responsibility for the call to solely the first service node;

wherein

the sixth means are responsive to the detection by ceasing to communicate call traffic of the call between the second service node and the mobile user terminal;

the seventh means are responsive to the detection by ceasing to communicate call traffic of the call between the second service node and the one call processing unit and by communicating a notification thereof to the one call processing unit across the communication channel between the second service node and the one call processing unit; and

the eighth means are responsive to receipt of the notification from the seventh means by ceasing to duplicate and to discard the call traffic.

43. In a wireless-access telecommunications system that includes at least one mobile wireless-call user terminal, a plurality of service nodes each for providing wireless-call services to wireless-call user terminals in its vicinity, and at last one interface node connected to the service nodes and having a plurality of call processing units each for interfacing a wireless call that extends between a user terminal and a service node to a telecommunications facility, the improvement comprising:

first means (244) in a first service node (master

     202), responsive to receiving incoming call traffic of the call from a mobile user terminal that is in the vicinity of the first service node, for sending, to the interface node, first packets containing the received incoming call traffic and each having a first address which identifies the call'"'"'s corresponding one of the call processing units;

second means (602, FIGS. 11-12) in the one call processing unit responsive to receiving the first packets, for sending the incoming call traffic contained in the first packets to a telecommunications facility;

third means (602, FIG.

     15) in the one call processing unit, responsive to receiving outgoing call traffic of the call from the telecommunications facility, for sending, to the first service node, second packets containing the received outgoing call traffic and each having a second address different from the first address and which identifies the first service node;

fourth means (243 and 245 of master

     202) in the first service node, responsive to receiving the second packets, for sending the outgoing call traffic contained in the second packets to the mobile user terminal;

fifth means (241 of master 202, FIG.

     27) in the first service node, responsive to a detection that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, for sending, to the second service node, a message specifying a third address different from the first address and which also identifies the one call processing unit;

sixth means (241 of slave 202, FIG.

     27) in a second service node (slave

     202), responsive to receiving the message, for sending, to the interface node, a third packet both (a) specifying a fourth address different from the second and the third addresses and which identifies the second service node and (b) having the third address;

seventh means (244 of slave

     202) in the second service node, responsive to receiving incoming call traffic of the call from the mobile user terminal subsequently to the second service node receiving the message, for sending, to the interface node, fourth packets containing the received incoming call traffic and each having the third address;

eighth means (602,

     970) in the one call processing unit, responsive to receiving the third packet, for storing the fourth address for use in the call by the one call processing unit;

the third means further responsive to receiving outgoing call traffic of the call from the telecommunications facility subsequently to the one call processing unit receiving the third packet, for sending the second packets to the first service node and also sending, to the second service node, fifth packets containing same received outgoing call traffic as the second packets and each having the fourth address;

ninth means (243 and 245 of slave

     202) in the second service node, responsive to receiving the fifth packets, for sending the outgoing call traffic contained in the fifth packets to the mobile user terminal; and

the second means further responsive to receiving both the first packets and the fourth packets both containing same received incoming call traffic subsequently to the one call processing unit receiving the third packet, for selecting the incoming call traffic contained by one of the received first and fourth packets that contain the same traffic and sending only the selected incoming call traffic to the telecommunications facility.

44. The improvement of claim 43 wherein

the third means are responsive to receiving the second packets subsequently to the one call processing unit receiving the third packet, for sending the outgoing call traffic contained in the received second packets to the mobile user terminal simultaneously with the ninth means sending the same outgoing call traffic contained in the fifth packets to the mobile user terminal.

45. The improvement of claim 43 wherein the first means, the third means, and the seventh means each include:

means for frame-relaying packets thereby to send the packets.

46. The improvement of claim 43 in a wireless-access telecommunications system wherein the interface node is connected to the service nodes by a plurality of telecommunications links, wherein:

the sixth and the seventh means send the third and the fourth packets from the second service node to the interface node on a same one of the links; and

the second and the eighth means both respectively receive the fourth and the third packets on a same one of the links.

47. The improvement of claim 43 wherein:

the second address identifies a wireless channel of the first service node which corresponds to the call; and

the fourth address identifies a wireless channel of the second service node which corresponds to the call.

48. The improvement of claim 47 wherein:

the first and the third addresses identify different logical ports of the one call processing unit.

49. The improvement of claim 43 wherein:

each packet comprises a Link Access Protocol-D Channel (LARD) packet; and

each different address comprises a unique Data Link Connection Identifier (DLCI).

50. The improvement of claim 43 in a wireless-access telecommunications system that further includes a controller for assigning individual call processing units to handle individual calls, including assigning the one call processing unit to handle said call, wherein:

the first means comprise

means responsive to receiving incoming call traffic of the call from a mobile user terminal that is in the vicinity of the first service node, for sending, to the interface node, without involvement therein of the controller while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, first packets containing the received incoming call traffic and each having a first address which identifies the call'"'"'s corresponding one of the call processing units;

the second means comprise

tenth means responsive to receiving the first packets, for sending the incoming call traffic contained in the first packets to a telecommunications facility, without involvement therein of the controller while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the third means comprise

eleventh means responsive to receiving outgoing call traffic of the call from the telecommunications facility, for sending, to the first service node, without involvement therein of the controller while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, second packets containing the received outgoing call traffic and each having a second address different from the first address and which identifies the first service node;

the fourth means comprise

means responsive to receiving the second packets, for sending the outgoing call traffic contained in the second packets to the mobile user terminal, without involvement therein of the controller while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the fifth means comprise

means responsive to a detection that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, for sending, to the second service node, without involvement therein of the controller while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, a message specifying a third address different from the first address and which also identifies the one call processing unit;

the sixth means comprise

means responsive to receiving the message, for sending, to the interface node, without involvement therein of the controller while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, a third packet both (a) specifying a fourth address different from the second and the third addresses and which identifies the second service node and (b) having the third address;

the seventh means comprise

means responsive to receiving incoming call traffic of the call from the mobile user terminal subsequently to the second service node receiving the message, for sending, to the interface node, without involvement therein of the controller while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, fourth packets containing the received incoming call traffic and each having the third address;

the eighth means comprise

means responsive to receiving the third packet, for storing the fourth address for use in the call by the one call processing unit, without involvement therein of the controller while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the eleventh means are further responsive to receiving outgoing call traffic of the call from the telecommunications facility subsequently to the one call processing unit receiving the third packet, for sending the second packets to the first service node and also sending, to the second service node, fifth packets containing same received outgoing call traffic as the second packets and each having the fourth address, all without involvement therein of the controller while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the ninth means comprise

means responsive to receiving the fifth packets, for sending the outgoing call traffic contained in the fifth packets to the mobile user terminal, without involvement therein of the controller while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node; and

the tenth means are further responsive to receiving both the first packets and the fourth packets both containing same received incoming call traffic subsequently to the one call processing unit receiving the third packet, for selecting the incoming call traffic contained by one of the received first and fourth packets that contain the same traffic and sending only the selected incoming call traffic to the telecommunications facility, all without involvement therein of the controller while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node.

51. The improvement of claim 43 in a wireless-access telecommunications system that further includes a system controller for coordinating call-establishment operations of the service nodes and the interface nodes, including coordinating call-establishment operations of the first service node and the interface node for said call, wherein:

the first means comprise

means in the first service node, responsive to receiving incoming call traffic of the call from a mobile user terminal that is in the vicinity of the first service node, for sending, to the interface node, without involvement therein of the controller and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, first packets containing the receiving incoming call traffic and each having a first address which identifies the call'"'"'s corresponding one of the call processing units;

the second means comprise

means in the one call processing unit responsive to receiving the first packets, for sending, without involvement therein of the controller and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, the incoming call traffic contained in the first packets to a telecommunications facility;

the third means comprise

means in the one call processing unit, responsive to receiving outgoing call traffic of the call from the telecommunications facility, for sending, to the first service node, without involvement therein of the controller and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, second packets containing the received outgoing call traffic and each having a second address different from the first address and which identifies the first service node;

the fourth means comprise

means in the first service node, responsive to receiving the second packets, for sending, without involvement therein of the controller and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, the outgoing call traffic contained in the second packets to the mobile user terminal;

the fifth means comprise

means in the first service node, responsive to a detection that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, for sending, to the second service node, without involvement therein of the controller, a message specifying a third address different from the first address and which also identifies the one call processing unit;

the sixth means comprise

means in the second service node, responsive to receiving the message, for sending, to the interface node, without involvement therein of the controller and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, a third packet both (a) specifying a fourth address different from the second and the third addresses and which identifies the second service node and (b) having the third address;

the seventh means comprise

means in the second service node, responsive to receiving the incoming call traffic of the call from the mobile user terminal subsequently to the second service node receiving the message, for sending, to the interface node, without involvement therein of the controller and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, fourth packets containing the received incoming call traffic and each having the third address;

the eighth means comprise

means in the one call processing unit, responsive to receiving the third packet, for storing, without involvement therein of the controller and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, the fourth address for use in the call by the one call processing unit;

the third means further comprise

means responsive to receiving outgoing call traffic of the call from the telecommunications facility subsequently to the one call processing unit receiving the third packet, for sending the second packets to the first service node and also sending, to the second service node, fifth packets containing same received outgoing call traffic as the second packets and each having the fourth address, without involvement therein of the controller and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the ninth means comprise

means in the second service node, responsive to receiving the fifth packets, for sending, without involvement therein of the controller and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, the outgoing call traffic contained in the fifth packets to the mobile user terminal; and

the second means further comprise

means responsive to receiving both the first packets and the fourth packets both containing same received incoming call traffic subsequently to the one call processing unit receiving the third packet, for selecting the incoming call traffic contained by one of the received first and fourth packets that contain the same traffic and sending only the selected incoming call traffic to the telecommunications facility, without involvement therein of the controller and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node.

52. The improvement of claim 43 in a wireless-access telecommunications system that further includes an interface node controller for assigning individual call processing units to handle individual calls, including assigning the one of the call processing units to handle said call, and a supervisory controller for coordinating call-establishment operations of the service nodes and the interface node, including coordinating call-establishment operations of the first service node and the interface node for said call, wherein:

the first means compris

means in the first service node, responsive to receiving incoming call traffic of the call from a mobile user terminal that is in the vicinity of the first service node, for sending, to the interface node, without involvement therein of the controllers and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, first packets containing the received incoming call traffic and each having a first address which identifies the call'"'"'s corresponding one of the call processing units;

the second means comprise

means in the one call processing unit responsive to receiving the first packets, for sending, without involvement therein of the controllers and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, the incoming call traffic contained in the first packets to a telecommunications facility;

the third means comprise

means in the one call processing unit, responsive to receiving outgoing call traffic of the call from the telecommunications facility, for sending, to the first service node, without involvement therein of the controllers and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, second packets containing the received outgoing call traffic and each having a second address different from the first address and which identifies the first service node;

the fourth means comprise

means in the first service node, responsive to receiving the second packets, for sending, without involvement therein of the controllers and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, the outgoing call traffic contained in the second packets to the mobile user terminal;

the fifth means comprise

means in the first service node, responsive to a detection that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, for sending, to the second service node, without involvement therein of the controllers, a message specifying a third address different from the first address and which also identifies the one call processing unit;

the sixth means comprise

means in the second service node, responsive to receiving the message, for sending, to the interface node, without involvement therein of the controllers and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, a third packet both (a) specifying a fourth address different from the second and the third addresses and which identifies the second service node and (b) having the third address;

the seventh means comprise

means in the second service node, responsive to receiving incoming call traffic of the call from the mobile user terminal subsequently to the second service node receiving the message, for sending, to the interface node, without involvement therein of the controllers and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, fourth packets containing the received incoming call traffic and each having the third address;

the eighth means comprise

means in the one call processing unit, responsive to receiving the third packet, for storing, without involvement therein of the controllers and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, the fourth address for use in the call by the one call processing unit;

the third means further comprise

means responsive to receiving outgoing call traffic of the call from the telecommunications facility subsequently to the one call processing unit receiving the third packet, for sending the second packets to the first service node and also sending, to the second service node, fifth packets containing same received outgoing call traffic as the second packets and each having the fourth address, without involvement therein of the controllers and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node;

the ninth means comprise

means in the second service node, responsive to receiving the fifth packets, for sending, without involvement therein of the controllers and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, the outgoing call traffic contained in the fifth packets to the mobile user terminal; and

the second means further comprise

means responsive to receiving both the first packets and the fourth packets both containing same received incoming call traffic subsequently to the one call processing unit receiving the third packet, for selecting the incoming call traffic contained by one of the received first and fourth packets that contain the same traffic and sending only the selected incoming call traffic to the telecommunications facility, without involvement therein of the controllers and while the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node.

53. The improvement of claim 52 further comprising:

tenth means responsive to detection of an origination of the call, for notifying thereof the supervisory controller;

means in the interface node controller responsive to a message sent by the supervisory controller upon being notified of the call origination, for establishing a call connection for the call between the one call processing unit and the telecommunications facility;

eleventh means in the first service node responsive to a message sent by the supervisory controller upon being notified of the call origination and directing establishment of a call connection for the call between the first service node and the one call processing unit, for sending to the interface node a third packet both (a) specifying the second address and (b) having the first address, to establish the directed connection; and

the eighth means in the one call processing unit being responsive to receipt of the third packet, for storing the second address for use in the call by the third means.

54. The improvement of claim 53 wherein:

each packet comprises a Link Access Protocol-D Channel (LAPD) packet; and

each different address comprises a unique Data Link Connection Identifier (DLCI).

55. The improvement of claim 43 wherein:

the fifth means include means responsive to a detection that the mobile user terminal has moved from the vicinity of the first service node to the vicinity of the second service node, for sending a second message to the second service node to notify the second service node of transfer of responsibility for serving the call from the first service node to the second service node;

the improvement further comprises

tenth means in the first service node, responsive to the detection, for sending to the interface node a sixth packet having the first address and indicating that the first service node is ceasing to serve the call;

the first means and the fourth means are responsive to the detection by ceasing to send call traffic of the call received at the first service node, whereby the second means cease to receive the first packets; and

the third means are responsive to receipt of the sixth packet by ceasing to send the second packets.

56. The improvement of claim 55 wherein:

the first means include means responsive to the detection, for sending to the interface node a seventh packet, prior to the sending of the sixth packet, having the first address and indicating that the first service node is ceasing to serve the call;

the third means include means, responsive to receipt of the seventh packet, for simultaneously sending to the first and the second service node respectively an eighth and a ninth packet respectively having the second and the fourth address and indicating that the first service node is ceasing to serve the call; and

the fourth means and the ninth means each include means responsive to receipt of one of the eighth and the ninth packets, for simultaneously sending an indication from both the first and the second service nodes to the mobile user terminal that the first service node is ceasing to serve the call.

57. The improvement of claim 56 wherein:

each packet comprises a Link Access Protocol-D Channel (LAPD) packet; and

each different address comprises a unique Data Link Connection Identifier.

58. The improvement of claim 43 wherein:

the fifth means include means responsive to a detection that the mobile user terminal is returning from the vicinity of both the first and the second service nodes to the vicinity of the first service node, for sending a second message to the second service node to notify the second service node of return of responsibility for serving the call from the both the first and the second service nodes to the first service node;

the sixth means include means responsive to receipt of the second message, for sending to the interface node a sixth packet having the third address and indicating that the second service node is ceasing to serve the call;

the seventh means and the ninth means are responsive to receipt of the second message by ceasing to send call traffic of the call received at the second service node, whereby the second means cease to receive the fourth packets; and

the third means are responsive to receipt of the sixth packet by ceasing to send the fifth packets.

59. The improvement of claim 58 wherein:

the first means include means responsive to the detection, for sending to the interface node a seventh packet, prior to the sending of the sixth packet, having the first address and indicating that the second node is ceasing to serve the call;

the third means include means, responsive to receipt of the seventh packet, for simultaneously sending to the first and the second service nodes respectively an eighth and a ninth packet respectively having the second and the fourth address and indicating that the second service node is ceasing to serve the call; and

the fourth means and the ninth means each include means responsive to receipt of one of the eighth and the ninth packets, for simultaneously sending an indication from both the first and the second service nodes to the mobile user terminal that the second service node is ceasing to serve the call.

60. The improvement of claim 59 wherein:

each packet comprises a Link Access Protocol-D Channel (LAPD) packet; and

each different address comprises a unique Data Link Connection Identifier (DLCI).

61. The improvement of claim 58 further comprising:

tenth means (241 of slave 202, FIG.

     29) in the second service node responsive to the sending of the sixth packet, for sending a third message to the first service node indicating that the second service node has ceased to serve the call.

62. A call processing unit for a wireless-access telecommunications system that includes at least one mobile wireless-call user terminal, a plurality of service nodes each for providing wireless-call services to wireless-call user terminals in its vicinity, and at least one interface node connected to the service nodes and having a plurality of the call processing units each for interfacing a wireless call that extends between a user terminal and a service node to a telecommunications facility, comprising:

first means (602, FIGS. 11-12) responsive to receiving from a first service node first packets containing incoming call traffic received by the first service node from a mobile user terminal in the vicinity of the first service node and each having a first address which identifies the receiving call processing unit as the call'"'"'s corresponding one of a plurality of call processing units, for sending the incoming call traffic contained in the first packets from the one call processing unit to a telecommunications facility;

second means (602, FIG.

     15) responsive to receiving outgoing call traffic of the call from the telecommunications facility, for sending second packets containing the received outgoing call traffic and each having a second address different from the first address and which identifies the first service node, from the one call processing unit to the first service node for receipt and transmission of the outgoing call traffic contained in the second packets by the first service node to the mobile user terminal in the vicinity of the first service node;

third means (602,970) responsive to receiving from a second service node a third packet specifying a fourth address different from the second address and which identifies the second service node and having a third address different from the first and the fourth addresses and which also identifies the one call processing unit, which third address was specified by a message sent by the first service node to the second service node in response to detection that the mobile user terminal is moving from the vicinity of the first service node to the vicinity of the second service node, for storing the fourth address for use in the call by the second means;

the first means further responsive to receiving from the first and the second service nodes respectively the first packets and fourth packets both containing same incoming call traffic received by respectively the first and the second service nodes from the mobile user terminal and the fourth packets each having the third address, subsequently to the receipt of the third packet, for repeatedly selecting the incoming call traffic contained by one of the received first and fourth packets which contain the same traffic and sending only the selected incoming call traffic to the telecommunications facility; and

the second means further responsive to receiving outgoing call traffic of the call from the telecommunications facility subsequently to the receipt of the third packet, for sending the second packets from the one call processing unit to the first service node and sending fifth packets containing same received outgoing call traffic as the second packets and each having the fourth address, from the one call processing unit to the second service node, for transmission by both the first and the second service nodes of the same outgoing call traffic to the mobile user terminal.

63. An individual service node for a wireless-access telecommunications system that includes at least one mobile wireless-call user terminal, a plurality of service nodes each for providing wireless-call services to wireless-call user terminals in its vicinity, and at least one interface node connected to the service nodes and having a plurality of call processing units each for interfacing a wireless call that extends between a user terminal and service node to a telecommunications facility, comprising:

first means (244) responsive to receiving incoming call traffic of a call from a mobile user terminal in the vicinity of said individual service node (master

     202), for sending first packets containing the received incoming call traffic and each having a first address which identifies the call'"'"'s corresponding one of the call processing units, from said individual service node to the interface node for receipt and transmission of the incoming call traffic by the one call processing unit to a telecommunications facility;

second means (243,245) responsive to receiving second packets from the one call processing unit containing outgoing call traffic for the call received by the one call processing unit from the telecommunications facility and each having a second address different from the first address and which identifies said individual service node, for sending the outgoing call traffic contained in the second packets from the first service node to the mobile user terminal in the vicinity of this service node;

third means (241 of master

     202) responsive to detection that the mobile user terminal is moving from the vicinity of said individual service node to the vicinity of another service node (slave

     202), for sending a message specifying a third address different from the first address and which also identifies the one call processing unit, from said individual service node to the other service node;

fourth means (241 of slave

     202) responsive to receiving a message from the other service node sent by the other service node in response to detection that a mobile user terminal in the vicinity of the other service node and having a call interfaced by the one call processing unit to a telecommunications facility is moving from the vicinity of the other service node to the vicinity of said individual service node and specifying the first address, for sending to the interface node a third packet both (a) specifying the second address different from the third address and from a fourth address which identifies the other service node and (b) having the first address, for use of the fourth address for the call by the one call processing unit;

the first means responsive to receiving incoming call traffic of the call from the mobile user terminal moving either from the vicinity of the other service node to the vicinity of said individual service node or from the vicinity of said individual service node to the vicinity of the other service node subsequently to sending or receiving of the message, for sending the first packets containing the received incoming call traffic to the interface node at a same time as the other service node sends to the interface node fourth packets each having the third address and containing the same received incoming call traffic received from the same mobile user terminal, for receipt by the one call processing unit of the same incoming call traffic from both the first and the second service nodes, selection by the one call processing unit of incoming call traffic received from one of the first and the second service nodes, and sending of only the selected incoming call traffic to the telecommunications facility; and

the second means responsive to receiving the second packets containing outgoing call traffic received by the one call processing unit from the telecommunications facility for the call of the mobile user terminal moving either from the vicinity of the other service node to the vicinity of said individual service node or from the vicinity of said individual service node to the vicinity of the other service node, subsequently to the one call processing unit receiving the third packet and sent by the one call processing unit at a same time as fifth packets each having the fourth address and containing the same outgoing call traffic are sent by the one call processing unit to the other service node, for sending the outgoing call traffic contained in the second packets from the first service node to the mobile user terminal at a same time as the other service node sends the same outgoing call traffic contained in the fifth packets to the same mobile user terminal.