Patent Application
20240259932
The present disclosure relates to a method of a Session Management Function (SMF) apparatus, a method of a Network Slice Admission Control Function (NSACF) apparatus, a method of an Access and Mobility Management Function (AMF) apparatus, a method of an apparatus related to SMF, a SMF apparatus, a NSACF apparatus, an AMF apparatus and an apparatus related to SMF.
Network slicing feature was defined in the 3GPP release 15 and release 16 specifications. GSMA 5GJA has introduced in NPL 5 the concept of Generic network Slice Template (GST) from which several Network Slice Types descriptions can be derived. Some of these parameters in the GST point explicitly to the definition of parameters and bounds on the service delivered to the end customer. For instance, the GST aims at the limitation of the number of PDU sessions per network slice, or the number of devices supported per network slice, or the maximum UL or DL data rate per network slice. NPL 4 identified and addressed the gaps that needed to be filled in providing support for the GST parameters enforcement and the suitable solutions to address these gaps.
However, there are still outstanding issues related to EPS and 5GS interworking and mobility.
In an aspect of the present disclosure, a method of a Session Management Function (SMF) apparatus includes communicating with a Network Slice Admission Control Function (NSACF) apparatus and sending a message to the NSACF apparatus for a Network Slice Admission Control (NSAC). The message includes information related to a handover from Evolved Packet System (EPS) to 5th Generation System (5GS) and information indicating the NSAC is not supported in the EPS.
In an aspect of the present disclosure, a method of a Network Slice Admission Control Function (NSACF) apparatus includes receiving a message from a Session Management Function (SMF) apparatus. The message includes first information related to a handover from Evolved Packet System (EPS) to 5th Generation System (5GS) and second information indicating a Network Slice Admission Control Function (NSAC) is not supported in the EPS. The method includes accepting a PDU Session related to the handover in a case where the number of PDU Sessions on the 5GS reaches to a predetermined threshold value and the message includes the first information and the second information.
In an aspect of the present disclosure, a method of an Access and Mobility Management Function (AMF) apparatus includes communicating with a Network Slice Admission Control Function (NSACF) apparatus and sending a message to the NSACF apparatus for a Network Slice Admission Control (NSAC). The message includes information related to a handover from Evolved Packet System (EPS) to 5th Generation System (5GS) and information indicating the NSAC is not supported in the EPS.
In an aspect of the present disclosure, a method of a Network Slice Admission Control Function (NSACF) apparatus includes receiving a message from an Access and Mobility Management Function (AMF) apparatus. The message includes first information related to a handover from Evolved Packet System (EPS) to 5th Generation System (5GS) and second information indicating a Network Slice Admission Control Function (NSAC) is not supported in the EPS. The method includes accepting a registration of a User Equipment (UE) related to the handover in a case where the number of UEs registered on 5GS reaches to a predetermined threshold value and the message includes the first information and the second information.
In an aspect of the present disclosure, a method of an apparatus related to Session Management Function (SMF) includes communicating with a Network Slice Admission Control Function (NSACF) apparatus and sending a message to the NSACF apparatus for a Network Slice Admission Control (NSAC). The message includes information related to Radio Access Technology (RAT) of a User Equipment (UE).
In an aspect of the present disclosure, a method of a Session Management Function (SMF) apparatus includes communicating with a Network Slice Admission Control Function (NSACF) apparatus and sending a message to the NSACF apparatus for a Network Slice Admission Control (NSAC). The message includes information related to Radio Access Technology (RAT) of a User Equipment (UE). The RAT is a target RAT for a handover of the UE.
In an aspect of the present disclosure, a method of a Network Slice Admission Control Function (NSACF) apparatus includes receiving a first message from an apparatus related to Session Management Function (SMF). The first message includes information related to first Radio Access Technology (RAT) of a
User Equipment (UE). The method includes receiving a second message from an Access and Mobility Management Function (AMF) apparatus. The second message includes second information related to second RAT of the UE. The second RAT is a target RAT for a handover of the UE. The method includes accepting a PDU Session related to the handover in a case where the number of PDU Sessions on the second RAT reaches to a predetermined threshold value and the first RAT is mapped to the second RAT.
In an aspect of the present disclosure, a method of an Access and Mobility Management Function (AMF) apparatus includes communicating with a Network Slice Admission Control Function (NSACF) apparatus and sending a message to the NSACF apparatus for a Network Slice Admission Control (NSAC). The message includes information related to Radio Access Technology (RAT) of a User Equipment (UE). The RAT is a target RAT for a handover of the UE.
In an aspect of the present disclosure, a method of a Network Slice Admission Control Function (NSACF) apparatus includes receiving a first message from an apparatus related to Session Management Function ((SMF). The first message includes information related to first Radio Access Technology (RAT) of a User Equipment (UE). The method includes receiving a second message from an Access and Mobility Management Function (AMF) apparatus. The second message includes second information related to second RAT of the UE. The second RAT is a target RAT for a handover of the UE. The method includes accepting a PDU Session related to the handover in a case where the number of UEs on the second RAT reaches to a predetermined threshold value and the first RAT is mapped to the second RAT.
In an aspect of the present disclosure, a Session Management Function (SMF) apparatus includes means for communicating with a Network Slice Admission Control Function (NSACF) apparatus and means for sending a message to the NSACF apparatus for a Network Slice Admission Control (NSAC). The message includes information related to a handover from Evolved Packet System (EPS) to 5th Generation System (5GS) and information indicating the NSAC is not supported in the EPS.
In an aspect of the present disclosure, a Network Slice Admission Control Function (NSACF) apparatus includes means for receiving a message from a Session Management Function (SMF) apparatus. The message includes first information related to a handover from Evolved Packet System (EPS) to 5th Generation System (5GS) and second information indicating a Network Slice Admission Control Function (NSAC) is not supported in the EPS and means for accepting a PDU Session related to the handover in a case where the number of PDU Sessions on the 5GS reaches to a predetermined threshold value and the message includes the first information and the second information.
In an aspect of the present disclosure, an Access and Mobility Management Function (AMF) apparatus includes means for communicating with a Network Slice Admission Control Function (NSACF) apparatus and means for sending a message to the NSACF apparatus for a Network Slice Admission Control (NSAC). The message includes information related to a handover from Evolved Packet System (EPS) to 5th Generation System (5GS) and information indicating the NSAC is not supported in the EPS.
In an aspect of the present disclosure, a Network Slice Admission Control Function (NSACF) apparatus includes means for receiving a message from an Access and Mobility Management Function (AMF) apparatus. The message includes first information related to a handover from Evolved Packet System (EPS) to 5th Generation System (5GS) and second information indicating a Network Slice Admission Control Function (NSAC) is not supported in the EPS. The NSACF apparatus includes means for accepting a registration of a User Equipment (UE) related to the handover in a case where the number of UEs registered on 5GS reaches to a predetermined threshold value and the message includes the first information and the second information.
In an aspect of the present disclosure, an apparatus related to Session Management Function (SMF) includes means for communicating with a Network Slice Admission Control Function (NSACF) apparatus and means for sending a message to the NSACF apparatus for a Network Slice Admission Control (NSAC). The message includes information related to Radio Access Technology (RAT) of a User Equipment (UE).
In an aspect of the present disclosure, a Session Management Function (SMF) apparatus includes means for communicating with a Network Slice Admission Control Function (NSACF) apparatus and means for sending a message to the NSACF apparatus for a Network Slice Admission Control (NSAC). The message includes information related to Radio Access Technology (RAT) of a User Equipment (UE). The RAT is a target RAT for a handover of the UE.
In an aspect of the present disclosure, a Network Slice Admission Control Function (NSACF) apparatus includes means for receiving a first message from an apparatus related to Session Management Function (SMF). The first message includes information related to first Radio Access Technology (RAT) of a
User Equipment (UE). The NSACF apparatus includes means for receiving a second message from an Access and Mobility Management Function (AMF) apparatus. The second message includes second information related to second RAT of the UE. The second RAT is a target RAT for a handover of the UE. The NSACF apparatus includes means for accepting a PDU Session related to the handover in a case where the number of PDU Sessions on the second RAT reaches to a predetermined threshold value and the first RAT is mapped to the second RAT.
In an aspect of the present disclosure, an Access and Mobility Management Function (AMF) apparatus includes means for communicating with a Network Slice Admission Control Function (NSACF) apparatus and means for sending a message to the NSACF apparatus for a Network Slice Admission Control (NSAC). The message includes information related to Radio Access Technology (RAT) of a User Equipment (UE). The RAT is a target RAT for a handover of the UE.
In an aspect of the present disclosure, a Network Slice Admission Control Function (NSACF) apparatus includes means for receiving a first message from an apparatus related to Session Management Function (SMF). The first message includes information related to first Radio Access Technology (RAT) of a User Equipment (UE). The NSACF apparatus includes means for receiving a second message from an Access and Mobility Management Function (AMF) apparatus. The second message includes second information related to second RAT of the UE. The second RAT is a target RAT for a handover of the UE. The NSACH apparatus includes means for accepting a PDU Session related to the handover in a case where the number of UEs on the second RAT reaches to a predetermined threshold value and the first RAT is mapped to the second RAT.
In an aspect of the present disclosure, a method of a first apparatus includes communicating with a second apparatus, sending, to the second apparatus and a first parameter indicating that a communication apparatus is changing communication system from a first communication system to a second communication system and a second parameter indicating that network slice control is supported or not supported.
In an aspect of the present disclosure, a method of a second apparatus includes,
In an aspect of the present disclosure, a method of a third apparatus includes communicating with a second apparatus and sending, to the second apparatus, a first parameter indicating that a communication apparatus is changing communication system from a first communication system to a second communication system and a second parameter indicating that network slice control is supported or not or not supported.
In an aspect of the present disclosure, a method of a second apparatus includes receiving, from a first apparatus, a first parameter indicating that a communication apparatus is changing communication system from a first communication system to a second communication system and a second parameter indicating that network slice control is supported or not supported and accepting a communication apparatus registration in a case where the second apparatus receives the first parameter and the second parameter.
In an aspect of the present disclosure, a method of a second apparatus includes receiving, from a first system, a third parameter indicating a first Radio Access Technology (RAT) type, receiving, from a third apparatus, a fourth parameter indicating a second RAT type and accepting Protocol Data Unit (PDU) session in a case where the second apparatus receives the third parameter and the fourth parameter.
In an aspect of the present disclosure, a method of a second apparatus includes receiving, from a first system, a third parameter indicating a first Radio Access Technology (RAT) type, receiving, from a third apparatus, a fourth parameter indicating a second RAT type and accepting a communication apparatus registration in a case where the second apparatus receives the third parameter and the fourth parameter.
Each of aspects and elements included in the each aspects described below may be implemented independently or in combination with any other. These aspects include novel characteristics different from one another. Accordingly, these aspects contribute to achieving objects or solving problems different from one another and contribute to obtaining advantages different from one another.
The 3GPP SA2 Working Group will continue addressing these open issues within the Rel-17 standardization work as planned in NPL 6.
One of the outstanding problems is how to control the number of UEs registered with a network slice and the number of the PDU Sessions established on a network slice in the case of EPS and 5GS interworking and mobility. In NPL 6 the SA2 noted its intention to ‘finalize the support for EPC interworking’ during the 3GPP Rel-17 standardization work.
This disclosure and aspects in the disclosure relate to Network Slice Admission Control in EPS to 5GS intersystem change or EPS to 5GS handover.
For the purposes of the present document, the abbreviations given in NPL 1 and the following apply. An abbreviation defined in the present document takes precedence over the definition of the same abbreviation, if any, in NPL 1.
For the purposes of the present document, the terms and definitions given in NPL 1 and the following apply. A term defined in the present document takes precedence over the definition of the same term, if any, in NPL 1.
Those skilled in the art will appreciate that elements in the figures are illustrated for simplicity and may not have necessarily been drawn to scale. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the figures by conventional symbols, and the figures may show only those specific details that are pertinent to understanding the Aspects of the present disclosure so as not to obscure the figures with details that will be readily apparent to those skilled in the art having the benefit of the description herein.
For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the Aspect illustrated in the figures and specific language will be used to describe them. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended. Such alterations and further modifications in the illustrated system, and such further applications of the principles of the disclosure as would normally occur to those skilled in the art are to be construed as being within the scope of the present disclosure.
The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such a process or method. Similarly, one or more devices or entities or sub-systems or elements or structures or components preceded by “comprises . . . a” does not, without more constraints, preclude the existence of other devices, sub-systems, elements, structures, components, additional devices, additional sub-systems, additional elements, additional structures or additional components. Appearances of the phrase “in an Aspect”, “in another Aspect” and similar language throughout this specification may, but not necessarily do, all refer to the same Aspect.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this disclosure belongs. The system, methods, and examples provided herein are only illustrative and not intended to be limiting.
In the following specification and the claims, reference will be made to a number of terms, which shall be defined to have the following meanings. The singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise.
As used herein, information is associated with data and knowledge, as data is meaningful information and represents the values attributed to parameters. Further knowledge signifies understanding of an abstract or concrete concept. Note that this example system is simplified to facilitate description of the disclosed subject matter and is not intended to limit the scope of this disclosure. Other devices, systems, and configurations may be used to implement the Aspects disclosed herein in addition to, or instead of, a system, and all such Aspects are contemplated as within the scope of the present disclosure.
Aspect 1A: Number of PDU Sessions control in EPS to 5GS handover—The Aspect 1A is a solution for the service continuity problem described in Use Case B in
In this Aspect, the NSACF manages the number of PDU Sessions per network slices. For example, the NSACF may manage the number of PDU Sessions of a network slice indicated by the S-NSSAI1. The number of PDU Sessions of a network slice indicated by the S-NSSAI1 may be called as the number of PDU Sessions per S-NSSAI1. In this Aspect, the number of the number of PDU Sessions per S-NSSAI1 has reached a predetermined number (e.g. a threshold of the number of PDU Sessions per S-NSSAI1, or the maximum number of PDU Sessions per S-NSSAI1).
Note that, the number of PDU Sessions per S-NSSAI1 may reach the maximum number of PDU Sessions per S-NSSAI1 at one timing, but the number of PDU Sessions per S-NSSAI1 may not reach the maximum number after the one timing due to release of the PDU Sessions.
In addition, the maximum number of PDU Sessions per S-NSSAI1 may be configured considering a margin. For example, the network (e.g. the NSACF) may accept a new PDU session even if the maximum number of PDU Sessions per S-NSSAI1 has reached.
The SMF may also include, in the Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate request message, the ‘NSAC support in EPS’ parameter (or any other notation for a parameter with the purpose to indicate to the NSACF whether NSAC, i.e. quota control in EPS is supported or not).
The ‘NSAC support in EPS’ parameter may be called as information indicating whether NSAC, i.e. quota control in EPS is supported or not.
For example, the SMF may determine that the UE handover is from EPS to 5GS based on information from the AMF during the handover procedure.
For example, the SMF may determine whether NSAC, i.e. quota control in EPS is supported or not based on information from the AMF during the handover procedure.
If the UE is coming from EPS e.g. handover from EPS to 5GS, the SMF includes the ‘EPS to 5GS handover’ parameter in the Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate request. If the NSAC, i.e. quota control is not supported in the EPS, the SMF also includes, in the Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate request, the ‘NSAC support in EPS’ parameter which indicates that the NSAC, i.e. quota control is not supported in the EPS.
However, the NSACF will still increase the number of the PDU Sessions counter for the network slice and the NSACF will also add the UE ID and PDU Session ID into the list of UEs and PDU Sessions maintained in the NSACF for that network slice. In addition, when the NSACF determines whether the PDU Session is rejected or not, the NSACF also determines whether DCN 1 is mapped to S-NSSAI 1. That is, the NSACF determines that DCN of handover source (i.e. 4G or EPS) corresponds to (or mapped to) S-NSSAI of handover target (i.e. 5G or 5GS).
In addition, when the NSACF determines whether to reject the PDU Session or not, the NSACF may also determine whether DCN 1 is mapped to S-NSSAI 1 (or whether E-UTRAN via EPS related to the DCN 1 is mapped to NR related to S-NSSAI 1).
For example, the NSACF may determine that DCN of handover source (i.e. 4G or EPS) corresponds to (or mapped to) S-NSSAI of handover target (i.e. 5G or 5GS) and may determine that the message includes the ‘EPS to 5GS handover’ parameter and the ‘NSAC support in EPS’ parameter indicating that NSAC i.e. quota control is not supported in the EPS, then the NSACF may determine not to reject the PDU Session. In other aspects, the NSACF may determine whether to reject the PDU Session or not in the same manner as mentioned above.
In one example, the NSACF may reject the PDU Session(s) if the maximum number of the PDU Sessions quota on the network slice (e.g. S-NSSAI1) has been reached and the number of established PDU sessions(s) has exceeded significantly the maximum allowed number of PDU Sessions (e.g. exceeded the allowed exception quota overflow number set up by configuration or operator policy in the NSACF).
In one example, the NSACF may reject the PDU Session(s) if the maximum number of the PDU Sessions on the network slice (e.g. S-NSSAI1) has been reached and the number of established PDU sessions is exceeded significantly from the maximum number.
For example, the NSACF sends, to the SMF, the Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate response including information indicating that the counting or the managing of the number for the PDU Sessions on the network slice (e.g. S-NSSAI1) is successful. In addition, the Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate response may include information indicating that transferring the PDU session related to the handover is accepted.
The NSACF returns Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate response may be called as the NSACF returns Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate rsp.
In another example, the UE intersystem change can be a handover from non-3GPP access to 3GPP access within the same PLMN. In this case the SMF indicates it to the NSACF in a new parameter in the Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate request. The new parameter may be called, for example ‘non-3GPP to 3GPP handover’ or ‘non-3gpp access’ or any other notation for a parameter to indicate that the UE is undergoing non-3GPP to 3GPP handover. Then the NSACF performs the following behaviour or processes:
It should be noted that the interaction with the NSACF via the Nnsacf_NumberOfPDUsPerSliceAvailability CheckUpdate request message could also be triggered by an SMF+PGW-C.
Aspect 1B: Number of registered UEs per network slice control EPS to 5GS handover—The Aspect 1B is a solution for the service continuity problem described in Use Case B in
In this Aspect, the NSACF manages the number of registered UEs per network slices. For example, the NSACF may manage the number of registered UEs of a network slice indicated by the S-NSSAI1. The number of registered UEs of a network slice indicated by the S-NSSAI1 may be called as the number of UEs registered with S-NSSAI1. In this Aspect, the number of UEs registered with S-NSSAI1 has reached a predetermined number (e.g. a threshold of the number of UEs registered with S-NSSAI1, or the maximum number of UEs registered with S-NSSAI1).
Note that, the number of UEs registered with S-NSSAI1 may reach the maximum number of UEs registered with S-NSSAI1 at one timing, but the number of UEs registered with S-NSSAI1 may not reach the maximum number after the one timing due to deregistration of the UE.
In addition, the maximum number of UEs registered with S-NSSAI1 may be configured considering a margin.
For example, the network (e.g. the NSACF) may accept a new PDU session even if the maximum number of PDU sessions per S-NSSAI1 has reached.
During the handover procedure the MME forwards an indicator “NSAC support in EPS” in the Forward Relocation Request message to the AMF. And the AMF knows whether the NSAC is supported or not in EPS.
In one example, in case of homogeneous support or not support of the NSAC in the EPS network, it is preconfigured in the AMF that the entire EPS supports “NSAC” or not. In case of non-homogenous support of NSAC in EPS, the AMF knows whether a particular MME supports NSAC or does not support NSAC feature in the EPS. For example, if the NSAC is supported in EPS, the MME sets the indicator “NSAC support in EPS” indicating that the NSAC is supported in EPS. For example, if the NSAC is not supported in EPS, the MME sets the indicator “NSAC support in EPS” indicating that the NSAC is not supported in EPS.
The AMF may also include, in the Nnsacf_NumberOfUEsPerSliceAvailabilityCheckUpdate request message, the ‘NSAC support in EPS’ parameter (or any other notation for a parameter with the purpose to indicate to the NSACF whether NSAC, i.e. quota control in EPS is supported or not).
The ‘NSAC support in EPS’ parameter may be called as information indicating whether NSAC, i.e. quota control in EPS is supported or not.
For example, the AMF may determine that the UE handover is from EPS to 5GS based on information from the MME during the handover procedure.
For example, the AMF may determine whether NSAC, i.e. quota control in EPS is supported or not based on information from the MME during the handover procedure.
For example, if the indicator “NSAC support in EPS” in the Forward Relocation Request message from the MME indicates that the NSAC is supported in EPS, the AMF may determine that the NSAC is supported in EPS and set the ‘NSAC support in EPS’ parameter indicating that the NSAC is supported in EPS.
For example, if the indicator “NSAC support in EPS” in the Forward Relocation Request message from the MME indicates that the NSAC is not supported in EPS, the AMF may determine that the NSAC is not supported in EPS and set the ‘NSAC support in EPS’ parameter indicating that the NSAC is not supported in EPS.
If the UE is coming from EPS e.g. a handover from EPS to 5GS, the AMF includes, in the Nnsacf_NumberOfUEsPerSlice AvailabilityCheckUpdate request, the ‘EPS to 5GS handover’ parameter.
If the NSAC, i.e. quota control is not supported in the EPS, the AMF also includes, in the Nnsacf_NumberOfUEsPerSlice AvailabilityCheckUpdate request, the ‘NSAC support in EPS’ parameter which indicates that the NSAC, i.e. quota control is not supported in the EPS.
For example, the NSACF sends, to the AMF, the Nnsacf_NumberOfUEsPerSliceAvailabilityCheckUpdate response including information indicating that the counting or the managing of the number for the UEs on the network slice (e.g. S-NSSAI1) is successful. In addition, the Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate response may include information indicating that the UE registration is accepted in the 5GS.
The Nnsacf_NumberOfUEsPerSliceAvailability CheckUpdate response may be called as Nnsacf_NumberOfUEsPerSlice AvailabilityCheckUpdate rsp.
In another example, the UE intersystem change can be a handover from non-3GPP access to 3GPP access within the same PLMN, In this case the AMF indicates it to the NSACF in a new parameter in the Nnsacf_NumberOfUEsPerSlice Availability Check Update request. The new parameter may be called, for example as ‘non-3GPP to 3GPP handover’ or ‘non-3gpp access’ or any other notation for a parameter to indicate that the UE is undergoing non-3GPP to 3GPP handover. Then the NSACF performs the following behaviour or processes:
For example, the AMF may determine the handover from non-3GPP access to 3GPP access based on information from the MME during the handover procedure.
For example, the AMF may determine whether the NSAC, i.e. quota control for the number of the registered UEs per network slice for UEs registered via the non-3GPP access is supported or not based on information from the MME during the handover procedure.
Yet in one further example the above Aspects can be also executed when the UE has a PDU Session for IMS voice. When a UE has a PDU Session for IMS voice, then the SMF indicates this to NSACF to get or confirm the quota for the S-NSSAI related to the PDU of the voice Session IMS in the Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate request message with a new ‘IMS Voice’ parameter for example or any other notation for a parameter to indicate that the PDU Session is related to IMS voice and the NSACF grants admission i.e. quota for the S-NSSAI even though the number of PDU Session established on the S-NSSAI has reached the maximum quota (i.e. the NSACF does not reject (or the NSACF accepts) the PDU Session of the IMS voice even though the number of PDU Session established on the S-NSSAI has reached the maximum number). For example, the SMF may determine that the UE has a PDU Session for IMS voice based on information from the AMF during the handover procedure.
The same principle would be applicable also during the NSAC, i.e. quota control for the number of the UEs registered with the network slice. In this case the AMF indicates in the Nnsacf_NumberOfUEsPerSlice Availability Check Update request message with a new ‘IMS Voice’ parameter for example or any other notation for a parameter to indicate that the UE registration is related to IMS voice and the NSACF grants admission i.e. quota for the S-NSSAI even though the number of registered UEs with the S-NSSAI has reached the maximum quota (i.e. the NSACF does not reject (or the NSACF accepts) the UE registration for IMS voice even though the number of registered UEs with the S-NSSAI has reached the maximum number). For example, the AMF may determine that the UE has a PDU Session for IMS voice based on information from the MME during the handover procedure.
This principle is also applicable for the case when the UE in Idle mode selects a cell connected to 5GS and the UE is performing idle mode mobility procedure from EPS to 5GS. In this case also the PDN connection/PDU sessions related to the IMS voice is transferred to the EPS even if the maximum number of UEs registered with the S-NSSAI or the maximum number of PDU Sessions established on the S-NSSAI has been reached.
It should be noted that the interaction with the NSACF via the Nnsacf_NumberOfUEsPerSlice AvailabilityCheckUpdate request message could also be triggered by the SMF+PGW-C.
The Solution 2 discloses the Network Slice Admission Control for PDU Session establishment per RAT type. When the UE performs handover between EPS and 5GS, the source system interacts with the NSACF to decrement the number of registered UEs to the network slice or the number of established PDU Sessions on the network slice. Then, the target system interacts with the NSACF to increment the number of registered UEs with the network slice or the number of established PDU Sessions on the network slice. With this sequence, there is a chance that the target system may reject the PDU Session to be activated at the target system due to unavailable quota (e.g. if the maximum number of UEs registered with the network slice or the maximum number of the PDU Sessions on the network slice has been reached).
The
Aspect 2A: Number of PDU Sessions control in EPS to 5GS handover in case Network Slice Admission Control takes place in EPS—The Aspect 2A is a solution for the service continuity problem described in Use Case B in
This solution, demonstrated in
The Nnsacf_NumberOfPDUsPerSliceAvailability CheckUpdate request message includes UE ID (i.e. identifier for the UE), PDU Session ID, and S-NSSAI1.
In addition, the SMF+PGW-C also includes, in the Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate request message, a parameter, for example called ‘RAT Type’ or any other notation for a parameter in order to indicate the current active RAT for the UE. In this case the RAT Type is set to E-UTRAN via EPS, for example.
For example, the ‘RAT Type=E-UTRAN via EPS’ may be information indicating that the RAT type which the UE uses is E-UTRAN via EPS. The ‘RAT Type=E-UTRAN via EPS’ may mean that the current RAT type is E-UTRAN via EPS.
For example, the SMF+PGW-C is apparatus or node having function for the SMF and function for the PGW-C. The SMF+PGW-C may determine that the RAT type is E-UTRAN via EPS based on information retrieved during the establishment the PDN connection.
For example, the NSACF may know that the DCN1 is mapped to the S-NSSAI1. Hence, the NSACF may treat the PDN connection for the UE as the PDU session on the S-NSSAI1 for the UE. Or the NSACF may treat the PDN connection for the UE as the PDU Session on the S-NSSAI1 which has been granted over the RAT type which is E-UTRAN via EPS. Then, the NSACF may increment the counter for the S-NSSAI1. In addition to the increment, for example, the NSACF may store and manage a record that the PDU Session establishment on S-NSSAI1 for the UE has been granted. The record that the PDU Session establishment on S-NSSAI1 for the UE has been granted may be called as a record that the PDU session establishment for the UE has been granted via the RAT type which is E-UTRAN via EPS. The mapping of the DCN1 and the S-NSSAI1 may be called as the mapping of the E-UTRAN via EPS related to the DCN 1 and the NR related to the S-NSSAI 1.
The Nnsacf_NumberOfPDUsPerSliceAvailability CheckUpdate request message includes UE ID, PDU Session ID, S-NSSAI1, and RAT Type=NR.
The SMF includes the ‘RAT Type’ parameter set to NR in order to indicate the current active RAT.
For example, the ‘RAT Type=NR’ may be information indicating that the RAT type which the UE uses after the handover is NR or information indicating that a target RAT type for the handover is NR. The ‘RAT Type=NR’ may mean that the RAT type is NR.
For example, the SMF may determine that the RAT type is NR based on information from the AMF during the handover procedure.
In one example, the NSACF may reject the PDU Session(s) if the maximum number of the PDU Sessions on the network slice (e.g. S-NSSAI1) has significantly exceeded the maximum number allowed PDU Session on the network slice (e.g. exceeded the allowed exception quota overflow number set up by operator configuration or operator policy in the NSACF).
In one example, the NSACF may reject the PDU Session(s) if the maximum number of the PDU Sessions on the network slice (e.g. S-NSSAI1) has been reached and the number of established PDU sessions is exceeded significantly from the maximum number.
For example, the NSACF sends, to the SMF, the Nnsacf_NumberOfPDUsPerSlice AvailabilityCheckUpdate response including information indicating that the counting or the managing of the number for the PDU Sessions on the network slice (e.g. S-NSSAI1) is successful. The Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate response may be called as Nnsacf_NumberOfPDUsPerSliceAvailabilityCheckUpdate rsp.
Aspect 2B: Number of UEs control in EPS to 5GS handover in case Network Slice Admission Control takes place in EPS—The Aspect 2B is a solution for the service continuity problem described in Use Case B in
In addition, the SMF+PGW-C also includes, in the Nnsacf_NumberOfUEsPerSlice AvailabilityCheckUpdate request message, a parameter, for example called ‘RAT Type’ or any other notation for a parameter in order to indicate the current active RAT. In this case the RAT Type is set to E-UTRAN via EPS, for example.
For example, the ‘RAT Type=E-UTRAN via EPS’ may be information indicating that the RAT type which the UE uses is E-UTRAN via EPS. The ‘RAT Type=E-UTRAN via EPS’ may mean that the current RAT type is E-UTRAN via EPS.
For example, the SMF+PGW-C is apparatus or node having function for the SMF and function for the PGW-C. The SMF+PGW-C may determine that the RAT type is E-UTRAN via EPS based on information retrieved during the establishment the PDN connection.
For example, the NSACF may know that the DCN1 is mapped to the S-NSSAI1. Hence, the NSACF may treat the UE which has attached over the RAT type which is E-UTRAN via EPS as the UE which has registered for the S-NSSAI 1 over the RAT type which is NR. Then, the NSACF may increment the counter for the S-NSSAI1.
In addition to the increment, the NSACF may store and manage a record that the UE has registered on S-NSSAI1. The record that the UE has registered on S-NSSAI1 may be called as a record that the UE has been registered via the RAT type which is E-UTRAN via EPS.
The Nnsacf_NumberOfUEsPerSlice Availability CheckUpdate request message includes UE ID, PDU Session ID, S-NSSAI1, and RAT Type=NR.
The AMF includes the ‘RAT Type’ parameter set to NR in order to indicate the current active RAT.
For example, the ‘RAT Type=NR’ may be information indicating that the RAT type which the UE uses after the handover is NR or information indicating that a target RAT type for the handover is NR. The ‘RAT Type=NR’ may mean that the RAT type is NR.
For example, the AMF may determine that the RAT type is NR based on information from the MME during the handover procedure.
In one example, the NSACF may reject the UE registration for the network slice if the maximum number of the registered UEs with the network slice (e.g. S-NSSAI1) has exceeded significantly the maximum allowed UE registrations on the network slice (e.g. exceeded the allowed exception quota overflow number set up by operator configuration or operator policy in the NSACF).
In one example, the NSACF may reject the UE registration if the maximum number of the UEs on the network slice (e.g. S-NSSAI1) has been reached and the number of registered UEs exceeded significantly from the maximum number.
For example, the NSACF sends, to the AMF, the Nnsacf_NumberOfUEsPerSliceAvailabilityCheckUpdate response including information indicating that the counting or the managing of the number for the UEs on the network slice (e.g. S-NSSAI1) is successful.
This disclosure and the aspects solve a problem with the service continuity at EPS to 5GS inter system change (or EPS to 5GS handover or EPS to 5GS mobility).
The telecommunication system 1 represents a system overview in which an end to end communication is possible. For example, UE 3 (or user equipment, ‘mobile device’ 3) communicates with other UEs 3 or service servers in the data network 20 via respective (R)AN nodes 5 and a core network 7.
The (R)AN node 5 supports any radio accesses including a 5G radio access technology (RAT), an E-UTRA radio access technology, a beyond 5G RAT, a 6G RAT and non-3GPP RAT including wireless local area network (WLAN) technology as defined by the Institute of Electrical and Electronics Engineers (IEEE).
The (R)AN node 5 may split into a Radio Unit (RU), Distributed Unit (DU) and Centralized Unit (CU). In some aspects, each of the units may be connected to each other and structure the (R)AN node 5 by adopting an architecture as defined by the Open RAN (O-RAN) Alliance, where the units above are referred to as O-RU, O-DU and O-CU respectively.
The (R)AN node 5 may be split into control plane function and user plane function. Further, multiple user plane functions can be allocated to support a communication. In some aspects, user traffic may be distributed to multiple user plane functions and user traffic over each user plane functions are aggregated in both the UE 3 and the (R)AN node 5. This split architecture may be called as ‘dual connectivity’ or ‘Multi connectivity’.
The (R)AN node 5 can also support a communication using the satellite access. In some aspects, the (R)AN node 5 may support a satellite access and a terrestrial access.
In addition, the (R)AN node 5 can also be referred as an access node for a non-wireless access. The non-wireless access includes a fixed line access as defined by the Broadband Forum (BBF) and an optical access as defined by the Innovative Optical and Wireless Network (IOWN).
The core network 7 may include logical nodes (or ‘functions’) for supporting a communication in the telecommunication system 1. For example, the core network 7 may be 5G Core Network (5GC) that includes, amongst other functions, control plane functions and user plane functions. Each function in a logical nodes can be considered as a network function. The network function may be provided to another node by adapting the Service Based Architecture (SBA).
A Network Function can be deployed as distributed, redundant, stateless, and scalable that provides the services from several locations and several execution instances in each location by adapting the network virtualization technology as defined by the European Telecommunications Standards Institute, Network Functions Virtualization (ETSI NFV).
The core network 7 may support the Non-Public Network (NPN). The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).
As is well known, a UE 3 may enter and leave the areas (i.e. radio cells) served by the (R)AN node 5 as the UE 3 is moving around in the geographical area covered by the telecommunication system 1. In order to keep track of the UE 3 and to facilitate movement between the different (R)AN nodes 5, the core network 7 comprises at least one access and mobility management function (AMF) 70. The AMF 70 is in communication with the (R)AN node 5 coupled to the core network 7. In some core networks, a mobility management entity (MME) or a mobility management node for beyond 5G or a mobility management node for 6G may be used instead of the AMF 70.
The core network 7 also includes, amongst others, a Session Management Function (SMF) 71, a User Plane Function (UPF) 72, a Policy Control Function (PCF) 73, a Network Exposure Function (NEF) 74, a Unified Data Management (UDM) 75, a Network Data Analytics Function (NWDAF) 76 and NSACF (Network Slice Admission Control Function) 77. In addition, the core network 7 may also include SMF+PGW-C. When the UE 3 is roaming to a visited Public Land Mobile Network (VPLMN), a home Public Land Mobile Network (HPLMN) of the UE 3 provides the UDM 75 and at least some of the functionalities of the SMF 71, UPF 72, and PCF 73 for the roaming-out UE 3.
The UE 3 and a respective serving (R)AN node 5 are connected via an appropriate air interface (for example the so-called “Uu” interface and/or the like). Neighboring (R)AN node 5 are connected to each other via an appropriate (R)AN node 5 to (R)AN node interface (such as the so-called “Xn” interface and/or the like). Each (R)AN node 5 is also connected to nodes in the core network 7 (such as the so-called core network nodes) via an appropriate interface (such as the so-called “N2”/“N3” interface(s) and/or the like). From the core network 7, connection to a data network 20 is also provided. The data network 20 can be an internet, a public network, an external network, a private network or an internal network of the PLMN. In case that the data network 20 is provided by a PLMN operator or Mobile Virtual Network Operator (MVNO), the IP Multimedia Subsystem (IMS) service may be provided by that data network 20. The UE 3 can be connected to the data network 20 using IPv4, IPV6, IPv4v6, Ethernet or unstructured data type.
The “Uu” interface may include a Control plane of Uu interface and User plane of Uu interface.
The User plane of Uu interface is responsible to convey user traffic between the UE 3 and a serving (R)AN node 5. The User plane of Uu interface may have a layered structure with SDAP, PDCP, RLC and MAC sublayer over the physical connection.
The Control plane of Uu interface is responsible to establish, modify and release a connection between the UE 3 and a serving (R)AN node 5. The Control plane of Uu interface may have a layered structure with RRC, PDCP, RLC and MAC sublayers over the physical connection.
For example, the following messages are communicated over the RRC layer to support AS signaling.
The UE 3 and the AMF 70 are connected via an appropriate interface (for example the so-called N1 interface and/or the like). The N1 interface is responsible to provide a communication between the UE 3 and the AMF 70 to support NAS signaling. The N1 interface may be established over a 3GPP access and over a non-3GPP access. For example, the following messages are communicated over the N1 interface.
The UE 3 may, for example, support the Non-Public Network (NPN). The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).
The UE 3 may, for example, be an item of equipment for production or manufacture and/or an item of energy related machinery (for example equipment or machinery such as: boilers; engines; turbines; solar panels; wind turbines; hydroelectric generators; thermal power generators; nuclear electricity generators; batteries; nuclear systems and/or associated equipment; heavy electrical machinery; pumps including vacuum pumps; compressors; fans; blowers; oil hydraulic equipment; pneumatic equipment; metal working machinery; manipulators; robots and/or their application systems; tools; molds or dies; rolls; conveying equipment; elevating equipment; materials handling equipment; textile machinery; sewing machines; printing and/or related machinery; paper converting machinery; chemical machinery; mining and/or construction machinery and/or related equipment; machinery and/or implements for agriculture, forestry and/or fisheries; safety and/or environment preservation equipment; tractors; precision bearings; chains; gears; power transmission equipment; lubricating equipment; valves; pipe fittings; and/or application systems for any of the previously mentioned equipment or machinery etc.).
The UE 3 may, for example, be an item of transport equipment (for example transport equipment such as: rolling stocks; motor vehicles; motor cycles; bicycles; trains; buses; carts; rickshaws; ships and other watercraft; aircraft; rockets; satellites; drones; balloons etc.).
The UE 3 may, for example, be an item of information and communication equipment (for example information and communication equipment such as: electronic computer and related equipment; communication and related equipment; electronic components etc.).
The UE 3 may, for example, be a refrigerating machine, a refrigerating machine applied product, an item of trade and/or service industry equipment, a vending machine, an automatic service machine, an office machine or equipment, a consumer electronic and electronic appliance (for example a consumer electronic appliance such as: audio equipment; video equipment; a loud speaker; a radio; a television; a microwave oven; a rice cooker; a coffee machine; a dishwasher; a washing machine; a dryer; an electronic fan or related appliance; a cleaner etc.).
The UE 3 may, for example, be an electrical application system or equipment (for example an electrical application system or equipment such as: an x-ray system; a particle accelerator; radio isotope equipment; sonic equipment; electromagnetic application equipment; electronic power application equipment etc.).
The UE 3 may, for example, be an electronic lamp, a luminaire, a measuring instrument, an analyzer, a tester, or a surveying or sensing instrument (for example a surveying or sensing instrument such as: a smoke alarm; a human alarm sensor; a motion sensor; a wireless tag etc.), a watch or clock, a laboratory instrument, optical apparatus, medical equipment and/or system, a weapon, an item of cutlery, a hand tool, or the like.
The UE 3 may, for example, be a wireless-equipped personal digital assistant or related equipment (such as a wireless card or module designed for attachment to or for insertion into another electronic device (for example a personal computer, electrical measuring machine)).
The UE 3 may be a device or a part of a system that provides applications, services, and solutions described below, as to “internet of things (IoT)”, using a variety of wired and/or wireless communication technologies.
Internet of Things devices (or “things”) may be equipped with appropriate electronics, software, sensors, network connectivity, and/or the like, which enable these devices to collect and exchange data with each other and with other communication devices. IoT devices may comprise automated equipment that follow software instructions stored in an internal memory. IoT devices may operate without requiring human supervision or interaction. IoT devices might also remain stationary and/or inactive for a long period of time. IoT devices may be implemented as a part of a (generally) stationary apparatus. IoT devices may also be embedded in non-stationary apparatus (e.g. vehicles) or attached to animals or persons to be monitored/tracked.
It will be appreciated that IoT technology can be implemented on any communication devices that can connect to a communications network for sending/receiving data, regardless of whether such communication devices are controlled by human input or software instructions stored in memory.
It will be appreciated that IoT devices are sometimes also referred to as Machine-Type Communication (MTC) devices or Machine-to-Machine (M2M) communication devices or Narrow Band-IoT UE (NB-IoT UE). It will be appreciated that a UE 3 may support one or more IoT or MTC applications.
The UE 3 may be a smart phone or a wearable device (e.g. smart glasses, a smart watch, a smart ring, or a hearable device).
The UE 3 may be a car, or a connected car, or an autonomous car, or a vehicle device, or a motorcycle or V2X (Vehicle to Everything) communication module (e.g. Vehicle to Vehicle communication module, Vehicle to Infrastructure communication module, Vehicle to People communication module and Vehicle to Network communication module).
The communications control module 552 (using its transceiver control sub-module) is responsible for handling (generating/sending/receiving) signalling between the (R)AN node 5 and other nodes, such as the UE 3, another (R)AN node 5, the AMF 70 and the UPF 72 (e.g. directly or indirectly). The signalling may include, for example, appropriately formatted signalling messages relating to a radio connection and a connection with the core network 7 (for a particular UE 3), and in particular, relating to connection establishment and maintenance (e.g. RRC connection establishment and other RRC messages), NG Application Protocol (NGAP) messages (i.e. messages by N2 reference point) and Xn application protocol (XnAP) messages (i.e. messages by Xn reference point), etc. Such signalling may also include, for example, broadcast information (e.g. Master Information and System information) in a sending case.
The controller 54 is also configured (by software or hardware) to handle related tasks such as, when implemented, UE mobility estimate and/or moving trajectory estimation.
The (R)AN node 5 may support the Non-Public Network (NPN). The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).
The (R)AN node 5 based on O-RAN architecture represents a system overview in which the (R)AN node is split into a Radio Unit (RU) 60, Distributed Unit (DU) 61 and Centralized Unit (CU) 62. In some aspects, each unit may be combined. For example, the RU 60 can be integrated/combined with the DU 61 as an integrated/combined unit, the DU 61 can be integrated/combined with the CU 62 as another integrated/combined unit. Any functionality in the description for a unit (e.g. one of RU 60, DU 61 and CU 62) can be implemented in the integrated/combined unit above. Further, CU 62 can separate into two functional units such as CU Control plane (CP) and CU User plane (UP). The CU CP has a control plane functionality in the (R)AN node 5. The CU UP has a user plane functionality in the (R)AN node 5. Each CU CP is connected to the CU UP via an appropriate interface (such as the so-called “E1” interface and/or the like).
The UE 3 and a respective serving RU 60 are connected via an appropriate air interface (for example the so-called “Uu” interface and/or the like). Each RU 60 is connected to the DU 61 via an appropriate interface (such as the so-called “Front haul”, “Open Front haul”, “F1” interface and/or the like). Each DU 61 is connected to the CU 62 via an appropriate interface (such as the so-called “Mid haul”, “Open Mid haul”, “E2” interface and/or the like). Each CU 62 is also connected to nodes in the core network 7 (such as the so-called core network nodes) via an appropriate interface (such as the so-called “Back haul”, “Open Back haul”, “N2”/“N3” interface(s) and/or the like). In addition, a user plane part of the DU 61 can also be connected to the core network nodes 7 via an appropriate interface (such as the so-called “N3” interface(s) and/or the like).
Depending on functionality split among the RU 60, DU 61 and CU 62, each unit provides some of the functionality that is provided by the (R)AN node 5. For example, the RU 60 may provide a functionalities to communicate with a UE 3 over air interface, the DU 61 may provide functionalities to support MAC layer and RLC layer, the CU 62 may provide functionalities to support PDCP layer, SDAP layer and RRC layer.
The communications control module 6052 (using its transceiver control sub-module) is responsible for handling (generating/sending/receiving) signalling between the RU 60 and other nodes or units, such as the UE 3, another RU 60 and DU 61 (e.g. directly or indirectly). The signalling may include, for example, appropriately formatted signalling messages relating to a radio connection and a connection with the RU 60 (for a particular UE 3), and in particular, relating to MAC layer and RLC layer.
The controller 604 is also configured (by software or hardware) to handle related tasks such as, when implemented, UE mobility estimate and/or moving trajectory estimation.
The RU 60 may support the Non-Public Network (NPN). The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).
As described above, the RU 60 can be integrated/combined with the DU 61 as an integrated/combined unit.
Any functionality in the description for the RU 60 can be implemented in the integrated/combined unit above.
The DU 61 may support the Non-Public Network (NPN). The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).
As described above, the RU 60 can be integrated/combined with the DU 61 or CU 62 as an integrated/combined unit. Any functionality in the description for DU 61 can be implemented in one of the integrated/combined unit above.
The CU 62 may support the Non-Public Network (NPN). The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).
As described above, the CU 62 can be integrated/combined with the DU 61 as an integrated/combined unit.
Any functionality in the description for the CU 62 can be implemented in the integrated/combined unit above.
The AMF 70 may support the Non-Public Network (NPN). The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).
The SMF 71 may support the Non-Public Network (NPN). The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).
Note that SMF+PGW-C may have same components to the SMF 71. In addition, the SMF+PGW-C has function of the PGW-C. The function of the PGW-C can be achieved by the components of the SMF+PGW-C.
The UDM 75 may support the Non-Public Network (NPN). The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).
The NSACF 77 may support the Non-Public Network (NPN). The NPN may be a Stand-alone Non-Public Network (SNPN) or a Public Network Integrated NPN (PNI-NPN).
Detailed aspects have been described above. As those skilled in the art will appreciate, a number of modifications and alternatives can be made to the above aspects whilst still benefiting from the disclosures embodied therein. By way of illustration only a number of these alternatives and modifications will now be described.
In the above description, the UE 3 and the network apparatus are described for ease of understanding as having a number of discrete modules (such as the communication control modules). Whilst these modules may be provided in this way for certain applications, for example where an existing system has been modified to implement the disclosure, in other applications, for example in systems designed with the inventive features in mind from the outset, these modules may be built into the overall operating system or code and so these modules may not be discernible as discrete entities. These modules may also be implemented in software, hardware, firmware or a mix of these.
Each controller may comprise any suitable form of processing circuitry including (but not limited to), for example: one or more hardware implemented computer processors; microprocessors; central processing units (CPUs); arithmetic logic units (ALUs); input/output (IO) circuits; internal memories/caches (program and/or data); processing registers; communication buses (e.g. control, data and/or address buses); direct memory access (DMA) functions; hardware or software implemented counters, pointers and/or timers; and/or the like.
In the above aspects, a number of software modules were described. As those skilled in the art will appreciate, the software modules may be provided in compiled or un-compiled form and may be supplied to the UE 3 and the network apparatus as a signal over a computer network, or on a recording medium. Further, the functionality performed by part or all of this software may be performed using one or more dedicated hardware circuits. However, the use of software modules is preferred as it facilitates the updating of the UE 3 and the network apparatus in order to update their functionalities.
In the above aspects, a 3GPP radio communications (radio access) technology is used. However, any other radio communications technology (e.g. WLAN, Wi-Fi, WiMAX, Bluetooth, etc.) and other fix line communications technology (e.g. BBF Access, Cable Access, optical access, etc.) may also be used in accordance with the above aspects.
Items of user equipment might include, for example, communication devices such as mobile telephones, smartphones, user equipment, personal digital assistants, laptop/tablet computers, web browsers, e-book readers and/or the like. Such mobile (or even generally stationary) devices are typically operated by a user, although it is also possible to connect so-called ‘Internet of Things’ (IoT) devices and similar machine-type communication (MTC) devices to the network. For simplicity, the present application refers to mobile devices (or UEs) in the description but it will be appreciated that the technology described can be implemented on any communication devices (mobile and/or generally stationary) that can connect to a communications network for sending/receiving data, regardless of whether such communication devices are controlled by human input or software instructions stored in memory.
Various other modifications will be apparent to those skilled in the art and will not be described in further detail here.
The whole or part of the example Aspects disclosed above can be described as, but not limited to, the following.
<5.15.11.14 Support of Network Slice Admission Control and Interworking with EPC>
If EPS counting is required for a network slice, the Network Slice Admission Control for maximum number of UEs and/or for maximum number of PDU Sessions per network slice is performed at the time of PDN connection establishment in case of EPC interworking. To support the NSAC for maximum number of UEs and/or for maximum number of PDU Sessions per network slice in EPC, the SMF+PGW-C is configured with the information indicating which network slice is subject to NSAC. During PDN connection establishment in EPC, the SMF+PGW-C selects an S-NSSAI associated with the PDN connection as described in clause 5.15.7.1. If the selected S-NSSAI by the SMF+PGW-C is subject to the NSAC, the SMF+PGW-C triggers interaction with NSACF to check the availability of the network slice, before the SMF+PGW-C provides the selected S-NSSAI to the UE. If the network slice is available, the SMF+PGW-C continues to proceed with the PDN connection establishment procedure.
The NSACF performs the following for checking network slice availability prior to returning a response to the SMF+PGW-C:
When the UE with ongoing PDN connection(s) moves from EPC to 5GC, the SMF+PGW-C triggers a request to decrease the number of the UE registration in NSACF and the AMF triggers a request to increase the number of the UE registration in NSACF when the UE is registered in the new AMF. If there are more than one PDN connections associated with the S-NSSAI, the NSACF may receive multiple requests for the same S-NSSAI from different SMF+PGW-Cs. When the UE with ongoing PDU session(s) moves from 5GC to EPC, the SMF+PGW-C triggers a request to increase the number of the UE registration in NSACF and the old AMF triggers a request to decrease the number of the UE registration in NSACF when the UE is deregistered in old AMF. If there are more than one PDU sessions associated with the S-NSSAI, the NSACF may receive multiple requests for the same S-NSSAI from different SMF+PGW-Cs. The NSACF maintains a list of UE IDs based on the requests from SMF+PGW-C(s) and AMF, and adjusts the current number of registrations accordingly.
When the UE with ongoing PDN connection(s) moves from EPC to 5GC, or from 5GC to EPC, the session continuity is guaranteed as the admission was granted at the time of PDN connection establishment, i.e. the number of PDU session is not counted again in 5GC.
Editor's note: NSAC mechanism during the mobility between EPC and 5GC can be revisited to make it align with 5GC mechanism, i.e. mobility between AMFs.
If the PDN connection associated with S-NSSAI is released in EPC, the SMF+PGW-C triggers a request (i.e. decrease) to NSACF for maximum number of PDU sessions per network slice control. The NSACF determines to decrease the current number of registrations and remove the UE identity from the list of UE IDs if the PDN connection(s) associated with S-NSSAI are all released in EPC.
Editor's note: It is FFS whether one NSACF is in charge of registration and session admission control, or there are respective NSCAFs for registration and session admission control, depending on the deployment scenarios.
NOTE: Network Slice Admission Control in EPC is not performed for the attachment without PDN connectivity.
If EPS counting is not required for a network slice, the Network Slice Admission Control for maximum number of UEs and/or for maximum number of PDU Sessions per network slice is performed when the UE moves from EPC to 5GC, i.e. when the UE performs mobility Registration procedure from EPC to 5GC (Network Slice Admission Control for maximum number of UEs per network slice) and/or when the PDN connections are handed over from EPC to 5GC (Network Slice Admission Control for maximum number of PDU Sessions per network slice). The SMF+PGW-C is configured with the information indicating the network slice is subject to NSAC only in 5GS. The PDN connection interworking procedure is performed as described in clause 5.15.7.1.
If the NSAC is not supported in EPS and the EPS to 5GS handover takes place, the NSACF shall not reject the registration of the UE even if the maximum number of the registered UEs with the network slice in 5GS has been reached or has been exceeded unless the number of the registered UEs has reached an overflow threshold, if one is configured in the NSACF by the operator. Similarly, the NSACF shall not reject the registration of the PDU Session even if the maximum number of the registered PDU Sessions with the network slice in 5GS has been reached or has been exceeded unless the number of the registered PDU Sessions has reached an overflow threshold, if one is configured in the NSACF by the operator.
The number of UEs per network slice availability check and update procedure is to update (i.e. increase or decrease) the number of UEs registered with a S-NSSAI which is subject to NSAC. The AMF is configured with the information indicating which network slice is subject to NSAC.
FIG. 4.2.11.2-1: Number of UEs per network slice availability check and update procedure (See
NOTE 1: Depending on the deployment, there may be different NSACF for different S-NSSAI subject to NSAC, and hence, during the registration, AMF triggers the Number of UEs per network slice availability check and update procedure to multiple NSACFs.
NOTE 2: The use case of having two entries temporarily in the NSACF for the same UE can happen during inter-AMF mobility when there is no UE context transfer and the UE requests to register with S-NSSAI(s) subject to NSAC already used in the old AMF. The old entry in the NSACF is removed by the old AMF.
If the update flag parameter from the AMF indicates decrease and if there is only one entry associated with the UE ID, the NSACF removes the UE ID from the list of UEs registered with the network slice for each of the S-NSSAI(s) indicated in the request from the AMF and also the NSACF decreases the number of UEs per network slice that is maintained by the NSACF for each of these network slices. If there are two entries associated with the UE ID, the NSACF removes the old entry and keeps the new entry.
The NSACF takes access type into account for increasing and decreasing the number of UEs per network slice as described in clause 5.15.11.1 of TS 23.501 [2].
If the EPS to 5GS handover parameter is included and the NSAC support in the EPS parameter indicates that NSAC is not supported in EPS, the NSACF shall not reject the registration of the UE even if the maximum number of the registered UEs with the network slice in 5GS has been reached or has been exceeded unless the number of the registered UEs has reached an overflow threshold, if one is configured in the NSACF by the operator.
At UE Registration procedure, if only some of the S-NSSAIs reached the maximum number of UEs per S-NSSAI, the AMF sends a Registration Accept message to the UE in which the AMF includes the rejected S-NSSAI(s) in the rejected NSSAI list for which the NSACF has indicated that the maximum number of UEs per network slice has been reached, and for each rejected S-NSSAI the AMF includes a reject cause set to ‘maximum number of UEs per network slice reached’ and optionally a back-off timer.
When for all the Requested S-NSSAI(s) provided in step 2 the NSACF returned the maximum number of UEs per network slice has been reached and if one or more subscribed S-NSSAIs are marked as default in the subscription data and not subject to Network Slice Admission Control, the AMF can decide to include these Default Subscribed S-NSSAIs in the Allowed NSSAI. Otherwise, the AMF rejects the UE request for registration. In the Registration Reject message the AMF includes the rejected S-NSSAI(s) in the rejected NSSAI parameter, and for each rejected S-NSSAI the AMF includes a reject cause to indicate that the maximum number of UEs per network slice has been reached and optionally a back-off timer.
NOTE 3: If the use case requires the UE to remain reachable at all times with at least one slice, it is recommended that at least one of the Subscribed S-NSSAIs is marked as the default S-NSSAI which is not subject to Network Slice Admission Control. This will ensure the UE is able to access to services even when maximum number of UEs per network slice has been reached.
Editor's note: It is FFS whether and how to restrict the signalling sent from the AMFs to the NSACF in case the maximum number of UEs has been reached for prolonged time.
The number of PDU Sessions per network slice availability check and update procedure is to update (i.e. increase or decrease) the number of PDU Sessions established on S-NSSAI which is subject to NSAC. The SMF is configured with the information indicating which network slice is subject to NSAC.
FIG. 4.2.11.4-1: Number of PDU Sessions per network slice availability check and update procedure (See
If the update flag parameter from the SMF indicates increase the current number of PDU Sessions per network slice and the maximum number of PDU Sessions established on the network slice has not been reached yet, the NSACF increases the number of PDU Sessions for that network slice. If the maximum number of PDU Sessions established on the network slice has already been reached, then the NSACF returns a result parameter indicating that the maximum number of PDU Sessions per network slice has been reached.
If the update flag parameter from the SMF indicates decrease the current number of PDU Sessions per network slice, the NSACF decreases the number of PDU Sessions for that network slice.
If the EPS to 5GS handover parameter is included and the NSAC support in the EPS parameter indicates that NSAC is not supported in EPS, the NSACF shall not reject the registration of the PDU Session even if the maximum number of the registered PDU Sessions with the network slice in 5GS has been reached or has been exceeded unless the number of the registered PDU Sessions has reached an overflow threshold, if one is configured in the NSACF by the operator.
In the case of a PDU Session Establishment failure, the SMF triggers another request to the NSACF with the update flag parameter equal to decrease in order to re-adjust back the PDU Session counter in the NSACF.
Editor's note: It is FFS how to achieve high admission control accuracy.
Editor's note: Whether SMF or AMF interacts with the NSACF is FFS.
Service Operation name: Nnsacf_NumberOfUEsPerSlice AvailabilityCheckAndUpdate
Description: Updates the number of UEs registered with a network slice (e.g. increase or decrease) when the UE registration status for a network slice subject to NSAC has changed. Also, if the number of the UEs registered with the network slice is to be increased and the Early Availability Check (EAC) mode in the NSACF is activated for that network slice (see Nnsacf_NumberOfUEsPerSliceEACNotify service operation), the NSACF first checks whether the number of UEs registered with the network slice has reached the maximum number of UEs per network slice threshold. If the maximum number of UEs registered with the network slice has already been reached, the UE registration for that network slice is rejected. If the EAC is not activated, the NSACF increases or decreases the number of UEs per network slice as per the input parameters below.
Inputs, Required: S-NSSAI(s), UE ID (SUPI), access type, update flag.
The S-NSSAI(s) parameter is a list of one or more network slices for which the number of UEs registered with a network slice is to be updated and checked if the maximum number of UEs per network slice threshold has already been reached.
The UE ID is used by the NSACF to maintain a list of UE IDs registered with the network slice. The NSACF also takes access type into account for increasing and decreasing the number of UEs per network slice as described in clause 5.15.11.1 of TS 23.501 [2].
The update flag input parameter indicates whether the number of UEs registered with a network slice is to be:
Inputs, Optional: EPS to 5GS handover, NSAC support in EPS
The EPS to 5GS handover parameter indicates that the UE is in process of handover from EPS.
The NSAC support in EPS parameter indicates whether the NSAC is supported or not in EPS.
The NSACF may optionally return the current status of the network slice availability (e.g. a percentage out of the max number of UEs registered with a network slice) in the availability status parameter. This information may be used for NSACF signalling and load balancing in case multiple NSACFs are serving the same network slice.
Editor's note: It is FFS how to support in case multi NSACF is supported, e.g. discover the same NSACF, coordination of the local maximum number among NSACF.
Outputs, Required: maximum number of UEs per network slice reached, availability status.
Service Operation name: Nnsacf_NumberOfPDUsPerSliceAvailability CheckAndUpdate
Description: Updates the number of PDU Sessions established on a network slice (e.g. increase or decrease). Also, if the number of PDU Sessions on the network slice is to be increased, the NSACF first checks whether the number of the PDU Sessions on that network slice has reached the maximum number of PDU Sessions per network slice threshold. If the maximum number of PDU Sessions on the network slice has already been reached, the PDU Session Establishment procedure is rejected.
Inputs, Required: S-NSSAI, update flag.
The S-NSSAI parameter is the network slice for which the number of PDU Sessions established on a network slice is to be updated.
The update flag input parameter indicates whether the number of the PDU Sessions established on that network slice is to be increased, for example at PDU Session Establishment procedure or decreased, for example at PDU Session Release procedure.
Inputs, Optional: EPS to 5GS handover, NSAC support in EPS
The EPS to 5GS handover parameter indicates that the UE is in process of handover from EPS.
The NSAC support in EPS parameter indicates whether the NSAC is supported or not in EPS.
Outputs, Required: maximum number of PDU Sessions per network slice reached, availability status
While the disclosure has been particularly shown and described with reference to exemplary Aspects thereof, the disclosure is not limited to these Aspects. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as defined by this document. For example, the Aspects above are not limited to 5GS, and the Aspects are also applicable to communication system other than 5GS.
The whole or part of the example Aspects disclosed above can be described as, but not limited to, the following supplementary notes.
supplementary note 1. A method of a Session Management Function (SMF) apparatus comprising:
supplementary note 2. A method of a Network Slice Admission Control Function (NSACF) apparatus comprising:
supplementary note 3. A method of an Access and Mobility Management Function (AMF) apparatus comprising:
supplementary note 4. A method of a Network Slice Admission Control Function (NSACF) apparatus comprising:
supplementary note 5. A method of an apparatus related to Session Management Function (SMF) comprising:
supplementary note 6. A method of a Session Management Function (SMF) apparatus comprising:
supplementary note 7. A method of a Network Slice Admission Control Function (NSACF) apparatus comprising:
supplementary note 8. A method of an Access and Mobility Management Function (AMF) apparatus comprising:
supplementary note 9. A method of a Network Slice Admission Control Function (NSACF) apparatus comprising:
supplementary note 10. A Session Management Function (SMF) apparatus comprising:
supplementary note 11. A Network Slice Admission Control Function (NSACF) apparatus comprising:
supplementary note 12. An Access and Mobility Management Function (AMF) apparatus comprising:
supplementary note 13. A Network Slice Admission Control Function (NSACF) apparatus comprising:
supplementary note 14. An apparatus related to Session Management Function (SMF) comprising:
supplementary note 15. A Session Management Function (SMF) apparatus comprising:
supplementary note 16. A Network Slice Admission Control Function (NSACF) apparatus comprising:
supplementary note 17. An Access and Mobility Management Function (AMF) apparatus comprising:
supplementary note 18. A Network Slice Admission Control Function (NSACF) apparatus comprising:
supplementary note 19. A method of a first apparatus comprising:
supplementary note 20. A method of a second apparatus comprising:
supplementary note 21. A method of a third apparatus comprising:
supplementary note 22. A method of a second apparatus comprising:
supplementary note 23. A method of a second apparatus comprising:
supplementary note 24. The method according to supplementary note 23, wherein the second apparatus detecting a communication system changing of a communication apparatus from a first communication system to a second communication system based on the third parameter and the fourth parameter.
supplementary note 25. A method of a second apparatus comprising:
supplementary note 26. The method according to supplementary note 25, wherein the second apparatus detecting a communication system changing of a communication apparatus from a first communication system to a second communication system based on the third parameter and the fourth parameter.
supplementary note 27. A method according to supplementary note 19, supplementary note 20, or supplementary note 22, wherein the first apparatus is Session Management Function (SMF).
supplementary note 28. The method according to supplementary note 19, supplementary note 20, supplementary note 21, supplementary note 22, supplementary note 23, supplementary note 24, supplementary note 25 or supplementary note 26, wherein the second apparatus is Network Slice Admission Control Function (NSACF).
supplementary note 29. The method according to supplementary note 19, supplementary note 20, supplementary note 21, supplementary note 22, supplementary note 24, supplementary note 25 or supplementary note 26, wherein the communication apparatus is User Equipment (UE).
supplementary note 30. The method according to supplementary note 19, supplementary note 20, supplementary note 21, supplementary note 22, supplementary note 24, or supplementary note 26, wherein the first communication system is Evolved Packet System (EPS).
supplementary note 31. The method according to supplementary note 19, supplementary note 20, supplementary note 21, supplementary note 22, supplementary note 24, or supplementary note 26, wherein the second communication system is 5G System (5GS).
supplementary note 32. The method according to supplementary note 21, supplementary note 23 or supplementary note 25, wherein the third apparatus is Access and Mobility Management Function (AMF).
While the invention has been particularly shown and described with reference to example embodiments thereof, the invention is not limited to these embodiments. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the claims.
This application is based upon and claims the benefit of priority from Indian provisional patent application No. 202111028662, filed on Jun. 25, 2021, the disclosure of which is incorporated herein in its entirety by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202111028662 | Jun 2021 | IN | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/022372 | 6/1/2022 | WO |
