Radio network control

Abstract

In connection with a radio access network that enables many-to-many communication between radio network controllers and radio nodes through a packet network, techniques for establishing a primary association between a first radio network controller (RNC) and a first radio node (RN), establishing a secondary association between the first RNC and a second RN, the first RN and the second RN being in different subnets, establishing a first traffic channel between a first access terminal and the first RNC when the first access terminal is in an active state in a coverage area of the first RN; and maintaining the first traffic channel between the first access terminal and the first RNC as the first access terminal moves from the coverage area of the first RN to any portion of the coverage area of the second RN while remaining in the active state.

1 . A method comprising: 
 in connection with a radio access network that enables many-to-many communication between radio network controllers and radio nodes through a packet network, 
 establishing a primary association between a first radio network controller and a first radio node and establishing a secondary association between the first radio network controller and a second radio node, the first radio node and the second radio node being in different subnets;  
 establishing a first traffic channel between a first access terminal and the first radio network controller when the first access terminal is in an active state in a coverage area of the first radio node; and  
 maintaining the first traffic channel between the first access terminal and the first radio network controller as the first access terminal moves from the coverage area of the first radio node to any portion of the coverage area of the second radio node while remaining in the active state.  
   
     
     
         2 . The method of  claim 1 , wherein: 
 packets passing between the first access terminal and the first radio network controller on the first traffic channel do not pass through any other radio network controller.    
     
     
         3 . The method of  claim 1 , further comprising: 
 establishing a primary association between a second radio network controller and the second radio node; and    performing an inter-radio network controller dormant handoff from the first radio network controller to the second radio network controller when the first access terminal is in a dormant state in any portion of the coverage area of the second radio node.    
     
     
         4 . The method of  claim 1 , wherein: 
 establishing the primary association comprises passing PN offset and IP address information from the first radio node to the first radio network controller; and    establishing the secondary association comprises passing PN offset and IP address information from the second radio node to the first radio network controller.    
     
     
         5 . The method of  claim 1 , further comprising: 
 receiving, from the first access terminal, a UATI_Request message upon a detection, by the first access terminal, of a change in a subnet identifier; and    triggering the inter-radio network controller dormant handoff from the first radio network controller to the second radio network controller in response to receipt of the UATI_Request message.    
     
     
         6 . The method of  claim 1 , further comprising: 
 establishing a primary association between the first radio network controller and a third radio node, the third radio node and the first radio node being in different subnets.    
     
     
         7 . The method of  claim 6 , further comprising: 
 broadcasting, by the first radio node, a first subnet identifier; and    broadcasting, by the third radio node, a third subnet identifier different from the first subnet identifier.    
     
     
         8 . The method of  claim 6 , further comprising: 
 receiving, from the first access terminal, a UATI_Request message upon a detection, by the first access terminal, of a change in a subnet identifier; and    without triggering an inter-radio network dormant handoff, assigning, by the first radio network controller, a new UATI to the first access terminal when the first access terminal is in dormant state after moving from the coverage area of the first radio node to any portion of a coverage area of the third radio node.    
     
     
         9 . The method of  claim 1 , further comprising: 
 employing a chassis-based hardware platform with multiple server cards to implement each of the radio network controllers.    
     
     
         10 . The method of  claim 9 , further comprising: 
 establishing the primary association between the first radio node and the first radio network controller by assigning the first radio node to one of the server cards on the first radio network controller; and    establishing a primary association between the second radio node and the second radio network controller by assigning the second radio node to one of the server cards on the second radio network controller.    
     
     
         11 . The method of  claim 10 , wherein establishing the primary association comprises passing PN offset information from each radio node to the server card of the radio network controller to which it is assigned, the method further comprising: 
 distributing the PN offset information from the server cards receiving the PN offset information to other server cards in the chassis-based hardware platform.    
     
     
         12 . The method of  claim 10 , further comprising: 
 establishing a transport-layer connection for signaling between each radio node and the server cards to which it is assigned in the radio network controllers.    
     
     
         13 . A computer program product, tangibly embodied in an information carrier, and adapted to work in a radio access network that enables many-to-many communication between radio network controllers and radio nodes through a packet network, the computer program product comprising instructions operable to cause data processing apparatus to: 
 establish a primary association between a first radio network controller and a first radio node and establish a secondary association between the first radio network controller and a second radio node;    establish a first traffic channel between a first access terminal and the first radio network controller when the first access terminal is in an active state in a coverage area of the first radio node; and    maintain the first traffic channel between the first access terminal and the first radio network controller as the first access terminal moves from the coverage area of the first radio node to any portion of the coverage area of the second radio node while remaining in the active state.    
     
     
         14 . The computer program product of  claim 13 , wherein the instructions are further operable to cause the data processing apparatus to: 
 pass packets between the first access terminal and the first radio network controller on the first traffic channel without requiring the packets to pass through any other radio network controller.    
     
     
         15 . The computer program product of  claim 13 , wherein the instructions are further operable to cause the data processing apparatus to: 
 establish a primary association between a second radio network controller and the second radio node.    
     
     
         16 . The computer program product of  claim 15 , wherein the instructions are further operable to cause the data processing apparatus to: 
 receive, from the first access terminal, a UATI Request message upon a detection, by the first access terminal, of a change in a subnet identifier; and    perform an inter-radio network controller dormant handoff from the first radio network controller to a second radio network controller when the first access terminal is in a dormant state in any portion of the coverage area of the second radio node.    
     
     
         17 . The computer program product of  claim 13 , wherein the instructions are further operable to cause the data processing apparatus to: 
 establish a primary association between a first radio network controller and a third radio node, the third radio node and the first radio node being in different subnets.    
     
     
         18 . The computer program product of  claim 17 , wherein the instructions are further operable to cause the data processing apparatus to: 
 receive, from the first access terminal, a UATI_Request message upon a detection, by the first access terminal, of a change in a subnet identifier; and    assign, by the first radio network controller, a new UATI to the first access terminal when the first access terminal is in dormant state in any portion of a coverage area of the third radio node.    
     
     
         19 . A system comprising: 
 a packet network that enables many-to-many communication between radio network controllers and radio nodes;    a first radio network controller having a primary association with a first radio node and a secondary association with a second radio node, the first radio node and the second radio node being in different subnets; and    wherein the first radio node establishes a first traffic channel with a first access terminal when the first access terminal is in an active state in a coverage area of the first radio node, and maintains the first traffic channel with the first access terminal when the first access terminal moves from the coverage area of the first radio node to any portion of the coverage area of the second radio node while remaining in the active state.    
     
     
         20 . The system of  claim 19 , wherein: 
 the first radio node forwards packets from the first access terminal to the first radio network controller on the first traffic channel without requiring the packets to pass through any other radio network controller.    
     
     
         21 . The system of  claim 19 , further comprising: 
 a second radio network controller having a primary association with the second radio node;    wherein the second radio network controller triggers an inter-radio network controller dormant handoff with the first radio network controller in response to a receipt of a UATI_Request message from the first access terminal when the first access terminal is in a dormant state in any portion of the coverage area of the second radio node.    
     
     
         22 . The system of  claim 19 , wherein the first radio network controller has a primary association with a third radio node, the first radio node and the third radio node being in different subnets; and 
 wherein the first radio network controller assigns a new UATI to the first access terminal in response to a receipt of a UATI_Request message from the first access terminal when the first access terminal is in a dormant state in any portion of a coverage area of the third radio node.