US-12628059-B2 - Mobility control in connection of network slices

US12628059B2US 12628059 B2US12628059 B2US 12628059B2US-12628059-B2

Abstract

There is provided a method, comprising: communicating a first data session on a first network slice with a source network node; receiving an indication indicating whether or not mapping the first data session to a second data session at a target network node requires switching to a second network slice, wherein the user equipment is equipped with a dual active protocol stack enabling the user equipment to communicate with the source network node and with the target network node during the handover process of the apparatus from a source cell provided by the source network node to a target cell provided by the target network node; deciding to continue the first data session on the first network slice with the source network node during the handover process; and deciding, based on the indication, when to start user plane data communication on the second data session with the target network node.

Inventors

Halit Murat GÜRSU
Philippe Godin
Ahmad Awada
Muhammad Naseer-Ul-Islam
Ömer BULAKCI

Assignees

NOKIA TECHNOLOGIES OY

Dates

Publication Date: 20260512
Application Date: 20220519

Claims (20)

1 . An apparatus, comprising: at least one processor and at least one memory including a computer program code, wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to: communicate a first data session on a first network slice with a source network node; receive an indication indicating whether or not mapping the first data session to a second data session at a target network node requires switching to a second network slice, wherein the apparatus is equipped with a dual active protocol stack enabling the apparatus to communicate with the source network node and with the target network node during the handover process of the apparatus from a source cell provided by the source network node to a target cell provided by the target network node; decide to continue the first data session on the first network slice with the source network node during the handover process; and decide, based on the indication, when to start user plane data communication on the second data session with the target network node.
2 . The apparatus of claim 1 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to: determine, based on the indication, that mapping the first data session to the second data session at the target network node does not require switching to the second network slice; decide to start user plane data communication on the second data session with the target network node upon completion of a random access process, thereby communicating on the first network slice with both the source network node and with the target network node during the handover process; and releasing the first data session with the source network node after the second data session with the target network node is ongoing.
3 . The apparatus of claim 1 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to: determine, based on the indication, that mapping the first data session to the second data session at the target network node requires switching to the second network slice; and decide to communicate with the source network node on the first data session on the first network slice during the handover process and start user plane data communication on the second data session on the second network slice with the target network node only after the second data session on the second network slice at the target network node has been setup.
4 . The apparatus of claim 3 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to: determine that the target network node does not support the first network slice; and avoid communicating with the target network node on the first network slice.
5 . The apparatus of claim 3 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to: determine that the first network slice is overloaded in the target network node; and avoid communicating with the target network node on the first net-work slice.
6 . The apparatus of claim 3 , wherein starting the user plane communication with the target network node comprises switching from the first data session on the first network slice at the source network node to the second data session on the second network slice at the target network node.
7 . The apparatus of claim 3 , wherein starting the user plane communication with the target network node comprises releasing the first data session on the first network slice with the source network node only after the second data session on the second network slice with the target network node is ongoing.
8 . The apparatus of claim 3 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to: send an indication to a core network where the apparatus indicates that slice remapping at the target network node is to be performed and that the apparatus comprises the dual active protocol stacks; and receive an acknowledgement from the core network according to which only the second network slice is allowed.
9 . The apparatus of claim 8 , wherein the indication to the core network is sent in a non-access stratum register request message or in a next generation application protocol path switch request.
10 . The apparatus of claim 1 , wherein starting the user plane communication with the target network node comprises at least starting to communicate user plane with the target network node in uplink direction.
11 . The apparatus of claim 1 , wherein the indication is received in a handover command received from the target network node or as an information element added by the source network node when transferring the handover command message from the target network node.
12 . The apparatus of claim 1 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to: signal to the source network node a capability to support a dual active protocol stack, DAPS, remapping function.
13 . The apparatus of claim 12 , wherein the DAPS remapping function is defined as DAPS capability modified with the ability to start the user plane communication with the target network node only after the second data session on the second network slice at the target network node has been setup.
14 . The apparatus of claim 1 , wherein the apparatus is or is comprised in a user equipment.
15 . An apparatus, comprising: at least one processor and at least one memory including a computer program code, wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to: send a handover request of a user equipment from a source network node to a target network node, wherein the request indicates that: a first data session between the source network node and the user equipment is on a first network slice, the user equipment is equipped with a dual active protocol stack enabling the user equipment to communicate with the source network node and with the target network node during the handover process, and the user equipment has ability to start the user plane communication with the target network node only after a second data session on a second network slice at the target network node has been setup; receive a response from the target network node, the response indicating whether mapping the first data session to the second data session at the target network node requires switching to the second network slice; and send a message, based on the response, to the user equipment indicating whether mapping the first data session to the second data session at the target network node requires switching to the second network slice during the handover.
16 . The apparatus of claim 15 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to: determine, based on the response from the target network node, that mapping the first data session to the second data session at the target network node requires switching to the second network slice; and include or transfer, in the message, information that mapping the first data session to the second data session at the target network node requires switching to the second network slice during the handover, wherein the indication configures the user equipment to: start user plane data communication on the second data session with the target network node only after the setup of the second data session on the second network slice at the target network node is completed, and avoid communicating with the target network node on the first network slice.
17 . The apparatus of claim 15 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to: continue the first data session on the first network slice with the user equipment during the handover process at least until the setup of the second data session on the second network slice at the target network node is completed.
18 . An apparatus, comprising: at least one processor and at least one memory including a computer program code, wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus to: receive a handover request of a user equipment from a source network node at a target network node, wherein the request indicates that: a first data session between the source network node and the user equipment is on a first network slice, the user equipment is equipped with a dual active protocol stack enabling the user equipment to communicate with the source network node and with the target network node during the handover process, and the user equipment has ability to start the user plane communication with the target network node only after a second data session on a second network slice at the target network node has been setup; determine whether at least one of: the target network node supports the first network slice or the first network slice is overloaded; and transmit a response to the source network node, the response indicating, based on the determining, whether mapping the first data session to the second data session at the target network node during the handover requires switching to the second network slice.
19 . The apparatus of claim 18 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to: build the response towards the user equipment; include, in the response, information that mapping the first data session to the second data session at the target network node requires switching to the second network slice during the handover, wherein the information configures the user equipment to: start user plane data communication on the second data session with the target network node only after the setup of the second data session on the second network slice at the target network node is completed, and avoid communicating with the target network node on the first network slice.
20 . The apparatus of claim 19 , wherein the at least one memory and the computer program code are configured, with the at least one processor, to cause the apparatus further to: avoid communicating with the user equipment on the first network slice when the first network slice is not supported or when the first network slice is over-loaded; and start user plane data communication on the second data session with the user equipment only after the setup of the second data session using the second network slice at the target network node is completed.

Description

RELATED APPLICATION This application was originally filed as a Patent Cooperation Treaty Application No. PCT/FI2022/050338 filed on May 19, 2022, which claims priority of a U.S. provisional application No. 63/209,431 filed on Jun. 11, 2021, both of which are hereby incorporated in their entirety. TECHNICAL FIELD Various example embodiments relate generally to mobility control, such as handovers, in connection of network slices. BACKGROUND It is common to handover a user equipment (UE) to another cell from a source cell when the UE moves across cell coverage areas. There is a need to avoid handover failures while keeping service/slice requirements, e.g., high data throughput, without large interruptions. BRIEF DESCRIPTION According to some aspects, there is provided the subject matter of the independent claims. Some further aspects are defined in the dependent claims. LIST OF THE DRAWINGS In the following, the invention will be described in greater detail with reference to the embodiments and the accompanying drawings, in which FIG. 1 presents a wireless communication network, according to an embodiment; FIG. 2 shows a connection establishment procedure, according to an embodiment; FIG. 3 shows DAPS handover, according to an embodiment; FIG. 4 shows a scenario where legacy handover may cause issues, according to some embodiments FIG. 5 depicts a handover suitable for slice remapping, according to an embodiment; FIG. 6-8 show methods, according to some embodiments; FIG. 9 shows a signaling flow diagram of a handover according to an embodiment; and FIGS. 10-11 illustrate apparatuses, according to some embodiments. DESCRIPTION OF EMBODIMENTS The following embodiments are exemplary. Although the specification may refer to “an”, “one”, or “some” embodiment(s) in several locations of the text, this does not necessarily mean that each reference is made to the same embodiment(s), or that a particular feature only applies to a single embodiment. Single features of different embodiments may also be combined to provide other embodiments. For the purposes of the present disclosure, the phrases “A or B” and “A and/or B” means (A), (B), or (A and B). For the purposes of the present disclosure, the phrase “A, B, and/or C” means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B, and C). Embodiments described may be implemented in a radio system, such as one comprising at least one of the following radio access technologies (RATs): Worldwide Interoperability for Micro-wave Access (WiMAX), Global System for Mobile communications (GSM, 2G), GSM EDGE radio access Network (GERAN), General Packet Radio Service (GRPS), Universal Mobile Telecommunication System (UMTS, 3G) based on basic wideband-code division multiple access (W-CDMA), high-speed packet access (HSPA), Long Term Evolution (LTE), LTE-Advanced, and enhanced LTE (eLTE). Term ‘eLTE’ here denotes the LTE evolution that connects to a 5G core. LTE is also known as evolved UMTS terrestrial radio access (EUTRA) or as evolved UMTS terrestrial radio access network (EUTRAN). A term “resource” may refer to radio resources, such as a physical resource block (PRB), a radio frame, a subframe, a time slot, a subband, a frequency region, a subcarrier, a beam, etc. The term “transmission” and/or “reception” may refer to wirelessly transmitting and/or receiving via a wireless propagation channel on radio resources The embodiments are not, however, restricted to the systems/RATs given as an example but a person skilled in the art may apply the solution to other communication systems provided with necessary properties. One example of a suitable communications system is the 5G system. The 3GPP solution to 5G is referred to as New Radio (NR). 5G has been envisaged to use multiple-input-multiple-output (MIMO) multi-antenna transmission techniques, more base stations or nodes than the current network deployments of LTE (a so-called small cell concept), including macro sites operating in co-operation with smaller local area access nodes and perhaps also employing a variety of radio technologies for better coverage and enhanced data rates. 5G will likely be comprised of more than one radio access technology/radio access network (RAT/RAN), each optimized for certain use cases and/or spectrum. 5G mobile communications may have a wider range of use cases and related applications including video streaming, augmented reality, different ways of data sharing and various forms of machine type applications, including vehicular safety, different sensors and real-time control. 5G is expected to have multiple radio interfaces, namely below 6 GHz, cmWave and mmWave, and being integrable with existing legacy radio access technologies, such as the LTE. The current architecture in LTE networks is distributed in the radio and centralized in the core network. The low latency applications and services in 5G require to bring the content close to the radio which leads to local break out and multi-access edge