Transport Layer Handling For Split Radio Network Architecture

Abstract

A radio network equipment central unit ( 20, 1700 ) receives a message ( 15 ) that indicates an update to a transport layer address of a radio network equipment distributed unit ( 10, 1600 ) from an old transport layer address ( 12 A) to a new transport layer address ( 12 B). The message ( 15 ) indicates the old transport layer address ( 12 A) and indicates the new transport layer address ( 12 B). The message ( 15 ) may be received from the radio network equipment distributed unit ( 10, 1600 ), or from a distributed unit of an integrated access backhaul donor. Regardless, for each of multiple user plane bearers or transport layer tunnels that are associated with the old transport layer address ( 12 A), the radio network equipment central unit ( 20, 1700 ) may update a transport layer address of that bearer or tunnel from the old transport layer address ( 12 A) to the new transport layer address ( 12 B).

What is claimed is: 
     
         1 . A method performed by a distributed unit (DU) of an integrated access backhaul (IAB) donor, wherein the DU is connected to a network node, the method comprising:
 determining that a transport layer address of the network node has changed; and   in response to the determining, transmitting, to a central unit (CU) of the IAB donor, a message that indicates an update to a transport layer address (TLA) of the network node from an old TLA to a new TLA, wherein the message comprises a mapping between the old TLA and the new TLA.   
     
     
         2 . The method of  claim 1 , wherein the message indicates said update as part of indicating an update to multiple TLAs of the network node, wherein the message indicates the update to multiple TLAs by indicating a mapping between old TLAs and new TLAs. 
     
     
         3 . The method of  claim 1 , wherein the message is an F1-AP gNB-DU configuration update message. 
     
     
         4 . The method of  claim 1 , wherein the message is agnostic to, or common for, user equipments served by the network node. 
     
     
         5 . The method of  claim 1 , wherein the network node is an IAB node for which the IAB donor is a donor. 
     
     
         6 . The method of  claim 1 , wherein multiple user plane bearers or transport layer tunnels are each associated with the old TLA, and wherein the message comprises a mapping between the old TLA and the new TLA for each of the multiple user plane bearers or transport layer tunnels. 
     
     
         7 . The method of  claim 1 , wherein the message indicates that, for each of multiple user plane bearers associated with the DU, a TLA of a transport layer tunnel endpoint of the user plane bearer has changed from the old TLA to the new TLA. 
     
     
         8 . The method of  claim 7 , wherein a user plane bear is an F1-U bearer or a data radio bearer (DRB), and wherein transport layer tunnel endpoints of a user plane bearer are endpoints of an F1 application part (AP) user plane (F1-U) tunnel or endpoints of a General Packet Radio Services (GPRS) Tunnelling Protocol (GTP) user plane (GTP-U) tunnel. 
     
     
         9 . The method of  claim 7 , wherein the message indicates, for each of the multiple user plane bearers associated with the DU, an update to transport layer information for the transport layer tunnel endpoint of the user plane bearer from old transport layer information to new transport layer information, wherein the message includes the old transport layer information and includes the new transport layer information, wherein the old transport layer information includes the old TLA and the new transport layer information includes the new TLA. 
     
     
         10 . A method performed by a central unit (CU) of an integrated access backhaul (IAB) donor that is connected to a network node, wherein the method comprises:
 receiving, from a distributed unit (DU) of the network node, a message that indicates an update to a transport layer address (TLA) of the network node from an old TLA to a new TLA, wherein the message comprises a mapping between the old TLA and the new TLA.   
     
     
         11 . The method of  claim 10 , wherein the message indicates said update as part of indicating an update to multiple TLAs of the network node, wherein the message indicates the update to multiple TLAs by indicating a mapping between old TLAs and new TLAs. 
     
     
         12 . The method of  claim 10 , wherein the message is an F1-AP gNB-DU configuration update message. 
     
     
         13 . The method of  claim 10 , wherein the message is agnostic to, or common for, user equipments served by the network node. 
     
     
         14 . The method of  claim 10 , wherein the TLA address of the network node is a transport network layer (TNL) address or an Internet Protocol (IP). 
     
     
         15 . The method of  claim 10 , wherein multiple user plane bearers or transport layer tunnels are each associated with the old TLA, and wherein the message comprises a mapping between the old TLA and the new TLA for each of the multiple user plane bearers or transport layer tunnels. 
     
     
         16 . The method of  claim 10 , wherein, for each of multiple user plane bearers associated with the DU, a TLA of a transport layer tunnel endpoint of the user plane bearer has changed from the old TLA to the new TLA. 
     
     
         17 . The method of  claim 16 , wherein a user plane bear is an F1-U bearer or a data radio bearer (DRB), and wherein transport layer tunnel endpoints of a user plane bearer are endpoints of an F1 application part (AP) user plane (F1-U) tunnel or endpoints of a General Packet Radio Services (GPRS) Tunnelling Protocol (GTP) user plane (GTP-U) tunnel. 
     
     
         18 . The method of  claim 16 , wherein the message indicates, for each of the multiple user plane bearers associated with the DU, an update to transport layer information for the transport layer tunnel endpoint of the user plane bearer from old transport layer information to new transport layer information, wherein the message includes the old transport layer information and includes the new transport layer information, wherein the old transport layer information includes the old TLA and the new transport layer information includes the new TLA. 
     
     
         19 . The method of  claim 10 , further comprising, for each of multiple user plane bearers served via the network node, updating a transport layer tunnel endpoint of the user plane bearer based on the received message, wherein updating a transport layer tunnel endpoint of the user plane bearer based on the received message comprises changing a TLA of the transport layer tunnel endpoint from the old TLA to the new TLA. 
     
     
         20 . A distributed unit (DU) of an integrated access backhaul (IAB) donor, wherein the DU is connected to a network node, the DU comprising:
 communication circuitry; and   processing circuitry configured to:
 making a determination that a transport layer address of the network node has changed; and 
 in response to the determination, transmit, to a central unit (CU) of the IAB donor, a message that indicates an update to a transport layer address (TLA) of the network node from an old TLA to a new TLA, wherein the message comprises a mapping between the old TLA and the new TLA.