UE RACH Resource Configuration Selection Function and resource prioritization to support slicing
A user device, UE, for a wireless communication network, is connectable to two or more of a plurality of network slices of the wireless communication network, wherein a slice specific random-access channel, RACH, resource configuration is associated with one or more of the plurality of slices. The UE is configured or pre-configured with slice specific RACH resource configurations for some or all of the plurality of slices. Responsive to a RACH event, the UE is to determine a slice that triggered and/or that is associated with the RACH event, and select the slice specific RACH resource configuration associated with the determined slice to be used for performing a RACH procedure.
1 . A user device, UE, for a wireless communication network having a plurality of tracking areas, the UE comprising:
one or more antennas or an antenna array having a plurality of antenna elements;
a signal processor; and
a transceiver,
wherein the UE is connectable to two or more of a plurality of network slices of the wireless communication network, wherein a slice specific random-access channel, RACH, resource configuration is associated with one or more of the plurality of network slices,
wherein the UE is configured or pre-configured with slice specific RACH resource configurations for some or all of the plurality of network slices,
wherein, responsive to an RACH event, the UE is to:
determine a slice that triggered and/or that is associated with the RACH event, and
select the slice specific RACH resource configuration associated with the determined slice to be used for performing an RACH procedure,
wherein, among the plurality of network slices, two or more slices share a slice specific RACH resource configuration,
wherein same slice specific RACH resource configurations are provided within a certain one of the plurality of tracking areas, and
wherein slice specific RACH resources defined by the same slice specific RACH resource configurations do not include common RACH resources.
2 . The user device, UE, of claim 1 , wherein
the UE is to perform the RACH procedure using the selected slice specific RACH resource configuration, or
the UE is to forward the selected slice specific RACH resource configuration to a further device for performing a RACH procedure, the UE being directly connected to the further device, e.g., via a sidelink connection or a different radio access technology (RAT), e.g. Bluetooth connection.
3 . The user device, UE, of claim 1 , wherein the UE is connected to at least two of the plurality of network slices simultaneously.
4 . The user device, UE, of claim 1 , wherein
the UE comprises one or more tables to hold the configured slice specific RACH resource configurations, or
the pre-configured slice specific RACH resource configurations are hardcoded, e.g., in the UE, or in a storage medium inserted into the UE, like a subscriber identification module, or in a modem firmware.
5 . The user device, UE, of claim 1 , wherein the UE is to be configured with the slice specific RACH resource configurations by
signaling RRC system information, or
a dedicated RRC signaling,
wherein the configured slice specific RACH resource configurations may be held in an RRC layer.
6 . The user device, UE, of claim 1 , wherein the UE is configured or pre-configured with a default or primary slice specific RACH resource configuration policy defining the slice specific RACH resource configurations.
7 . The user device, UE, of claim 6 , wherein the UE is to receive an updated or secondary slice specific RACH resource configuration policy from another entity of the wireless communication network, like a gNB or a sidelink UE or a relay, responsive to one or more criteria or responsive to a request of the UE, and the UE is to replace a current slice specific RACH resource configuration policy, like the default or primary slice specific RACH resource configuration policy, by the updated or secondary slice specific RACH resource configuration policy.
8 . The user device, UE, of claim 1 , wherein, responsive to a RACH event, the UE is to perform a slice specific RACH Resource Configuration Selection Function for determining the slice that triggered the RACH event, and for selecting the slice specific RACH resource configuration associated with the determined slice.
9 . The user device, UE, of claim 1 , wherein the UE is to determine the slice that triggered the RACH event and to select the slice specific RACH resource configuration associated with the determined slice jointly with or after a successful admission or access control for the slice.
10 . The user device, UE, of claim 1 , wherein, to perform the RACH procedure, the UE is to execute a general RACH Resource Selection Function selecting a specific physical RACH resource within the selected slice specific RACH resource configuration.
11 . The user device, UE, of claim 1 , wherein the RACH event comprises:
a radio link failure,
a beam failure,
an uplink data arrival in a user plane,
an uplink data arrival in a control plane,
a scheduling request or scheduling request failure,
a downlink data arrival with the UE being out of uplink synchronization,
a handover procedure,
a conditional handover procedure,
an initial access,
an RRC Connection Re-establishment,
a response to a paging,
a transition from an RRC IDLE state,
a transition from an RRC INACTIVE state, or
a trigger received via a sidelink, SL, e.g. SCI or RRC signaling via the SL.
12 . The user device, UE, of claim 1 , wherein, in case there is no ongoing uplink transmission on a PUSCH resource and/or no configured scheduling request, SR, on a PUCCH resource, for an uplink transmission of a data message from a certain application or service executed by the UE, the UE is to perform the RACH procedure using physical RACH resources of the RACH resource configuration that is associated with the slice that generated user data, wherein the slice is identified by one or more of a slice identity, a PDU session identity, a data network identity, a data network name, a PLMN identity, an access identity, an access category, a QoS flow identity, a radio bearer or logical channel identity.
13 . The user device, UE, of claim 1 , wherein, responsive to a failed PUCCH scheduling request to request resources for an uplink transmission on a PUSCH source, for an uplink transmission of a data message from a certain application or service executed by the UE, the UE is to perform the RACH procedure using physical RACH resources of the RACH resource configuration that is associated with the slice that generated user data, wherein the slice is identified by one or more of a slice identity, a PDU session identity, a data network identity, a data network name, a PLMN identity, an access identity, an access category, a QoS flow identity, a radio bearer or logical channel identity.
14 . The user device, UE, of claim 1 , wherein
a certain application or service executed by the UE is to provide a packet of an uplink user data request
to an uplink data queue together with an identification of the slice from which the packet originates, or
to an uplink data queue associated with the slice from which the packet originates,
responsive to determining that no uplink data transmission on PUSCH is ongoing and no scheduling request is possible on a pre-configured PUCCH, a MAC layer is to select the slice specific RACH resource configuration associated with the slice indicated by the identification or the uplink data queue, and
perform the RACH procedure using physical RACH resources of the selected slice specific RACH resource configuration.
15 . The user device, UE, of claim 14 , wherein, in case there is no slice specific RACH resource configuration associated with the slice from which the packet originates, the UE is to use physical RACH resources of
a configured or pre-configured fallback RACH resource configuration, or
a latest RACH resource configuration on which a RACH procedure was successful.
16 . The user device, UE, of claim 1 , wherein, in case there is no ongoing uplink transmission on a PUSCH resource and/or no configured scheduling request, SR, on a PUCCH resource, for an uplink transmission of a control message the UE is to perform the RACH procedure using:
in case the control message comprises information identifying the slice from which an uplink control data request originates, physical RACH resources of the slice specific RACH resource configuration that is associated with the slice that generated the uplink control data request, or
physical RACH resources of a primary RACH resource configuration, with one or more of the slice specific RACH resource configurations being configured, e.g., by a wireless communication system, as a default or primary RACH resource configuration.
17 . The user device, UE, of claim 1 , wherein two or more slices within a certain area, like a tracking area, TA, share the slice specific RACH resource configuration, and wherein, optionally, within the certain area, like the tracking area, TA, the UE is to receive from base stations of the wireless communication network the same slice specific RACH resource configurations.
18 . A base station, BS, for a wireless communication network having a plurality of tracking areas, the BS comprising:
one or more antennas or an antenna array having a plurality of antenna elements;
a signal processor; and
a transceiver,
wherein the BS is to support one or more of a plurality of slices of the wireless communication network, wherein a slice specific random-access channel, RACH, configuration is associated with one or more of the plurality of slices,
wherein the BS is to configure one or more user devices, UEs, with slice specific RACH resource configurations for some or all of the plurality of slices to which a UE is capable to connect to,
wherein, among the plurality of slices, two or more slices share a slice specific RACH resource configuration,
wherein same slice specific RACH resource configurations are provided within a certain one of the plurality of tracking areas, and
wherein slice specific RACH resources defined by the same slice specific RACH resource configurations do not include common RACH resources.
19 . The base station, BS, of claim 18 , wherein two or more slices within a certain area, like a tracking area, TA, share the slice specific RACH resource configuration, and wherein, optionally, within the certain area, like the tracking area, TA, the base station and one or more further base stations provide the same slice specific RACH resource configurations.
20 . A method for operating a user device, UE, for a wireless communication network having a plurality of tracking areas, wherein the UE is connectable to two or more of a plurality of network slices of the wireless communication network, wherein a slice specific random-access channel, RACH, resource configuration is associated with one or more of the plurality of network slices, and wherein the UE is configured or pre-configured with slice specific RACH resource configurations for some or all of the plurality of network slices, the method comprising:
responsive to a RACH event, determining a slice that triggered and/or that is associated with the RACH event, and
selecting the slice specific RACH resource configurations associated with a determined slice to be used for performing a RACH procedure,
wherein, among the plurality of network slices, two or more slices share a slice specific RACH resource configuration,
wherein same slice specific RACH resource configurations are provided within a certain one of the plurality of tracking areas, and
wherein slice specific RACH resources defined by the same slice specific RACH resource configurations do not include common RACH resources.