Patent Application
20230328833
Some embodiments of this description relate to a network node and a client device for disaster condition indication of a serving public land mobile network (PLMN) in a communication system. Furthermore, the some embodiments also relate to corresponding methods and a computer program.
During a disaster, cellular networks often get overloaded or become unavailable and users may therefore be denied services. Disasters can be man-made such as, e.g., a fire in a building or natural such as, e.g., an earthquake. When a disaster happens, a lot of people may try to call emergency services or each other. Due to multiple users requesting services at the same time, the network resources can get congested and users may not be able to get the requested services. Network failure can also happen during a disaster thereby the network becoming unavailable.
An objective of some embodiments is to provide a solution which mitigates or solves the drawbacks and problems of conventional solutions.
Another objective of some embodiments is to provide a disaster condition indication mechanism for communication systems.
The above and further objectives are solved by the subject matter of the independent claims. Further advantageous embodiments can be found in the dependent claims.
According to a first aspect, the above mentioned and other objectives are achieved with a network node for a communication system, the network node being associated with a serving public land mobile network (PLMN) for a first client device, and wherein the network node is configured to:
transmit a first control message to the first client device upon determining that the serving PLMN for the first client device is in a disaster condition, wherein the first control message indicates that the serving PLMN for the first client device is in the disaster condition.
That a network node is associated with a PLMN may be understood as to mean that the network node is a part of the PLMN.
That a PLMN is in disaster condition may be decided by a government agency and may be due to a natural disaster.
The serving PLMN may in some cases be the home PLMN.
An advantage of the network node according to the first aspect is that the client device is informed about the disaster condition of the serving PLMN so that the client device e.g. can move to another PLMN not in disaster condition to obtain service.
In an implementation form of a network node according to the first aspect, the network node is an access and mobility management function (AMF) of a core network, and wherein the first control message is a registration reject message, a de-registration request message, a configuration update command message, or a service reject message.
An advantage with this implementation form is that the client device will know that the network node is still able to communicate with the client device. So the client device can proactively move to another PLMN not in disaster condition for obtaining services.
In an implementation form of a network node according to the first aspect, the network node is a network access node of a radio access network (RAN) and wherein the first control message is a paging message.
An advantage with this implementation form is that a plurality of client devices may be informed at the same time about the disaster condition of the serving PLMN since the paging channel is monitored by all client devices and the paging message is received by all client devices.
In an implementation form of a network node according to the first aspect, the network node is a network access node of a RAN, and wherein the first control message is a radio resource control (RRC) connection reject message, a RRC connection release message, or a RRC serving PLMN disaster condition message.
An advantage with this implementation form is that the indication using RRC signalling may be more robust than, e.g., using non-access stratum (NAS) signalling.
In an implementation form of a network node according to the first aspect, the network node is a network access node of a RAN, and wherein the first control message is a system information block (SIB).
An advantage with this implementation form is that the client device continuously monitors the SIB which means that the client device will directly be aware of the disaster condition. Further, since the SIB is broadcasted all client devices in a served cell will be informed about the disaster condition of the serving PLMN.
In an implementation form of a network node according to the first aspect, the network node is further configured to:
redirect the first client device from the serving PLMN to a visiting PLMN for the first client device upon determining that the serving PLMN for the first client device is in a disaster condition.
An advantage with this implementation form is that this will enable the client device to get back to service possibly without any service interruption.
In an implementation form of a network node according to the first aspect, the visiting PLMN belongs to a 3rd generation partnership project (3GPP) or a non-3GPP system.
An advantage with this implementation form is that the non-3GPP system may be able to provide services to the client device as the non-3GPP system does not use the RAN of the 3GPP system which is the most susceptible entity in the network to get congested during a disaster condition.
In an implementation form of a network node according to the first aspect, the first control message further indicates at least one timer defining a start register time instance at the visiting PLMN for the first client device and/or a re-registration time instance at the serving PLMN for the first client device.
The timer defining a start register time instance may also be understood as a timer defining a minimum wait time to start registration. The timer defining a re-registration time instance may also be understood as a timer defining a minimum wait time to start re-registration.
An advantage with this implementation form is that the network does not get overloaded by too many client devices attempting registration to the network at the same time. Instead, the registrations may be distributed over a longer period of time. This also applies to the re-registration procedure to the serving PLMN.
In an implementation form of a network node according to the first aspect, the network node is further configured to:
transmit a second control message to a second client device upon determining that a serving PLMN for the second client device is in a disaster condition, wherein the second control message indicates that the serving PLMN for the second client device is in the disaster condition.
An advantage with this implementation form is that if the serving PLMN becomes unresponsive the client device will be able to obtain information about the disaster condition from other PLMNs still functioning.
In an implementation form of a network node according to the first aspect, the network node is a network access node of a RAN, and wherein the second control message is a SIB.
An advantage with this implementation form is that as the client device can get the SIB information for the other available PLMNs during a PLMN scanning procedure.
In an implementation form of a network node according to the first aspect, the network node is further configured to:
transmit a third control message to a second client device upon determining that a disaster condition for a serving PLMN for the second client device is over, wherein the third control message indicates that the disaster condition for the serving PLMN for the second client device is over.
An advantage with this implementation form is that the second client device may re-register at the serving PLMN for the second client device when the disaster condition is over.
According to a second aspect, the above mentioned and other objectives are achieved with a client device for a communication system, the client device being configured to be served by a serving PLMN, and further configured to:
An advantage of the client device according to the second aspect is that the client device is informed about the disaster condition of the serving PLMN. This means that the client device may initiate a PLMN selection procedure so as to find another PLMN that is not in disaster condition. Thereby, service interruption for the client device is avoided or shortened.
In an implementation form of a client device according to the second aspect, the client device is further configured to:
An advantage with this implementation form is that the client device will know which PLMNs to register to when the disaster condition happens.
In an implementation form of a client device according to the second aspect, the first control message and/or the second control message further indicates at least one timer defining a start register time instance at the visiting PLMN for the client device and/or a re-registration time instance at the serving PLMN for the client device.
The timer defining a start register time instance may also be understood as a timer defining a minimum wait time to start registration. The timer defining a re-registration time instance may also be understood as a timer defining a minimum wait time to start re-registration.
An advantage with this implementation form is that the network can configure client devices based on subscription what is the minimum time it needs to wait to perform a registration. This helps the network to prioritize some of client devices before others for faster and more effective registration.
In an implementation form of a client device according to the second aspect, the first network node is an AMF of a core network, and wherein the first control message is a registration reject message, a de-registration request message, a configuration update command message, or a service reject message.
An advantage with this implementation form is that client device may obtain information from the core network in NAS signalling even before the network becomes unresponsive which can happen when the serving PLMN is in the disaster condition.
In an implementation form of a client device according to the second aspect, the first network node is a network access node of a RAN, and wherein the first control message is a paging message.
An advantage with this implementation form is that a plurality of client devices can be informed at the same time about the disaster condition of the serving PLMN since the paging channel is monitored by all client devices and the paging message is received by all client devices.
In an implementation form of a client device according to the second aspect, the first network node is a network access node of a RAN, and wherein the first control message is a RRC connection reject message, a RRC connection release message, or a RRC serving PLMN disaster condition message.
An advantage with this implementation form is that the indication using RRC signalling may be more robust than, e.g., using NAS signalling.
In an implementation form of a client device according to the second aspect, the first network node is a network access node of a RAN, and wherein the first control message is a SIB.
An advantage with this implementation form is that the client device continuously monitors the SIB which means that the client device will directly be aware of the disaster condition. Further, since the SIB is broadcasted all client devices in a served cell will be informed about the disaster condition of the serving PLMN.
In an implementation form of a client device according to the second aspect, the second network node is a network access node of a RAN, and wherein the second control message is a SIB.
An advantage with this implementation form is that as the client device can get the SIB information for the other available PLMNs during a PLMN scanning procedure.
In an implementation form of a client device according to the second aspect, the client device is further configured to:
receive a third control message from a second network node associated with a visiting PLMN for the client device, wherein the third control message indicates that the disaster condition for the serving PLMN for the client device is over.
An advantage with this implementation form is that the client device may re-register at the serving PLMN when the disaster condition is over.
According to a third aspect, the above mentioned and other objectives are achieved with a method for a network node being associated with a serving PLMN for a first client device, the method comprising:
transmitting a first control message to the first client device upon determining that the serving PLMN for the first client device is in a disaster condition, wherein the first control message indicates that the serving PLMN for the first client device is in the disaster condition.
The method according to the third aspect can be extended into implementation forms corresponding to the implementation forms of the network node according to the first aspect. Hence, an implementation form of the method comprises the feature(s) of the corresponding implementation form of the network node.
The advantages of the methods according to the third aspect are the same as those for the corresponding implementation forms of the network node according to the first aspect.
According to a fourth aspect, the above mentioned and other objectives are achieved with a method for a client device being configured to be served by a serving PLMN, the method comprising:
The method according to the fourth aspect can be extended into implementation forms corresponding to the implementation forms of the client device according to the second aspect. Hence, an implementation form of the method comprises the feature(s) of the corresponding implementation form of the client device.
The advantages of the methods according to the fourth aspect are the same as those for the corresponding implementation forms of the client device according to the second aspect.
Some embodiments also relate to a computer program, characterized in program code, which when run by at least one processor, causes said at least one processor to execute any method according to one or more embodiments. Further, some embodiments also relate to a computer program product comprising a computer readable medium and said mentioned computer program, wherein said computer program is included in the computer readable medium, and comprises of one or more from the group: read-only memory (ROM), programmable ROM (PROM), erasable PROM (EPROM), flash memory, electrically EPROM (EEPROM), and a hard disk drive.
Further applications and advantages of one or more embodiments will be apparent from the following detailed description.
The appended drawings are intended to clarify and explain different embodiments, in which:
If a public land mobile network (PLMN) is not able to provide services such as, e.g., voice calls or mobile data services to a user equipment (UE) due to a disaster condition, there are often other PLMNs available in the area which may be able to provide service to the UE. However, those PLMNs could be configured to be forbidden PLMNs in the UE and the UE will hence never select one of those PLMNs.
To minimize service interruptions, it would be beneficial to enable a UE of a given PLMN to obtain service from another PLMN for an area where a disaster condition applies, even if the other PLMN is a forbidden PLMN for the UE under normal conditions. PLMN selection is a procedure which enables the UE to select the most appropriate PLMN at a particular point of time. Most of the time when the UE is in the home country, the home PLMN will be the most appropriate PLMN and the home PLMN will thus be the serving PLMN. To prevent the UE from switching from the home PLMN, roaming is often disabled inside the home country. Other PLMNs in the home country may, e.g., be added to a list of forbidden PLMNs so that the UE does not roam unnecessarily into these PLMNs.
Some embodiments of the present disclosure provide a disaster condition indication mechanism for communication systems thereby informing client devices, such as UEs, that a serving PLMN is in disaster condition. Thereby, the client devices may take appropriate measures such as, e.g., initiating a PLMN selection procedure.
The processor 102 of the network node 100 may be referred to as one or more general-purpose central processing units (CPUs), one or more digital signal processors (DSPs), one or more application-specific integrated circuits (ASICs), one or more field programmable gate arrays (FPGAs), one or more programmable logic devices, one or more discrete gates, one or more transistor logic devices, one or more discrete hardware components, and one or more chipsets. The memory 106 of the network node 100 may be a read-only memory, a random access memory, or a non-volatile random access memory (NVRAM).
The transceiver 104 of the network node 100 may be a transceiver circuit, a power controller, an antenna, or an interface which communicates with other modules or devices. In some embodiments, the transceiver 104 of the network node 100 may be a separate chipset or being integrated with the processor 102 in one chipset. In some embodiments, the processor 102, the transceiver 104, and the memory 106 of the network node 100 are integrated in one chipset.
With reference to
In some embodiments, the network node 100 is associated with the serving PLMN for a client device. That may be understood to mean that the network node 100 is part of the serving PLMN, e.g. a base station of a RAN or a function of a core network. In some embodiments, the network node 100 is not associated with the serving PLMN for a client device. Therefore, in some embodiments, the network node 100 is further configured to transmit a second control message 520 to a client device upon determining that a serving PLMN for the second client device is in a disaster condition. The second control message 520 indicates that the serving PLMN for the client device is in the disaster condition. This is also illustrated in
The processor 302 of the client device 300 may be referred to as one or more general-purpose CPUs, one or more DSPs, one or more ASICs, one or more FPGAs, one or more programmable logic devices, one or more discrete gates, one or more transistor logic devices, one or more discrete hardware components, and one or more chipsets. The memory 306 of the client device 300 may be a read-only memory, a random access memory, or a NVRAM.
The transceiver 304 of the client device 300 may be a transceiver circuit, a power controller, an antenna, or an interface which communicates with other modules or devices. In some embodiments, the transceiver 304 of the client device 300 may be a separate chipset or being integrated with the processor 302 in one chipset. In some embodiments, the processor 302, the transceiver 304, and the memory 306 of the client device 300 are integrated in one chipset.
With reference to
In some embodiments, the second network node 100′ may be a network access node of a RAN, and the second control message 520 is a SIB broadcasted by the second network node 100′.
It is noted that the client device 300 may receive the first control message 510 only; receive the second control message 520 only; or receive both the first control message 510 and the second control message 520.
When the client device 300 is informed or aware that the serving PLMN 610 is in the disaster condition the client device 300 may try to register to another PLMN that is not in disaster condition. Thereby, service interruption for the client device 300 is avoided or shortened. Therefore, in some embodiments, the client device 300 is configured to obtain a PLMN list comprising one or more visiting PLMNs. The client device 300 is further configured to register at a visiting PLMN in the PLMN list upon receiving the first control message 510 from the first network node 100 or the second control message 520 from the second network node 100′.
There are a number of different ways for the client device 300 to obtain the PLMN list. Non-limiting examples may be any of:
In some embodiments, the PLMN list comprises an identity of each PLMN in the PLMN list so that the PLMNs can be identified by the client device/UE.
For registration synchronization and resource control in the communication system 500 the first control message 510 and/or the second control message 520 may further indicate at least one timer T defining a start register time instance at the visiting PLMN 620 for the first client device 300 and/or a re-registration time instance at the serving PLMN 610 for the first client device 300. The timer defining a start register time instance may also be understood as a timer defining a minimum wait time to start registration at the visiting PLMN. The timer defining a re-registration time instance may also be understood as a timer defining a minimum wait time to start re-registration at the previously served PLMN which was under disaster condition.
In the following disclosure further exemplary implementation cases of the present solution will be described. The present mechanism for disaster condition indication may be realized using different types of control signalling and involving one or more communication procedures. These implementation cases are fully or partially set in a 3GPP context hence the terminology and system architecture herein used, but the discussed embodiments are exemplary, and should not be limited thereto. Furthermore, a network node may determine that the serving PLMN is in disaster condition in a number of different ways which is out of the scope of the present disclosure. However, it may be mentioned that the network node 100 or the network may be informed by a government agency, an operator, etc.
Furthermore,
For a service request procedure, in step I in
Correspondingly, for a registration request procedure, in step I in
In
The network may also initiate a configuration update command procedure by sending a configuration update command message with a new indication to the UE that the serving PLMN is in disaster condition and the UE needs to move to another PLMN not in disaster condition. Therefore, in Step I in
For both cases in step II in
In a general case the UE may perform a NAS signalling procedure and gets no response from the serving PLMN, e.g. since there is no radio resources available. In such case the UE may perform a scan on neighbouring PLMNs to see if their SIBs indicate that the serving PLMN is in the disaster condition. This is more or less in line with the embodiment shown in
Moreover,
In a first case in
Therefore, in some embodiments, the network node 100 may be configured to redirect the client device 300 from a serving PLMN 610 to a visiting PLMN 620 for a client device 300 upon determining that the serving PLMN 610 for the client device 300 is in a disaster condition. In this respect the previously mentioned PLMN list may be used for disaster condition PLMN selection. Also, the previously mentioned timer(s) T may be used so that the client device is aware of when to register or re-register.
The visiting PLMN 620 may belong to a 3GPP or a non-3GPP system. Generally, there may be two different access systems, which means there are two ways for the UE to access the core network. One may be 3GPP which, e.g., is GSM, WCDMA, LTE, NR and the other may be non-3GPP such as through a WiFi connection. So, the UE may move from a 3GPP system to a non-3GPP system, or vice versa.
In a second case in
For both cases in
Some embodiments relate to a further mechanism in which a client device 300 is informed that a disaster condition is over for its serving PLMN.
From a network node point of view, the network node 100 may further be configured to transmit a third control message 530 to a client device 300 upon determining that a disaster condition for a serving PLMN for the client device 300 is over. Hence, the third control message 530 indicates that the disaster condition for the serving PLMN for the client device 300 is over. This is illustrated in
From a client device 300 point of view and with further reference to
The signalling of the third control message 530 may be performed with the same or corresponding methods as the ones used for the first control message 510 signalling. In some embodiments, the third control message 530 may be:
One or more embodiments may be implemented in different communication standards. For example, the present solution may impact 3GPP TS 24.501 and TS 23.122 -NAS. The proposed changes may impact NR RRC specs, such as and 38.331 respectively. For example, the sections for “System information acquisition”, “RRC Connection Reject” and “RRC Connection Release”. In some embodiments, a new information element (IE) can be added for “RRCReject” and “RRCRelease” messages. In some embodiments, a new 5G mobility management (5GMM) cause value to indicate disaster condition may, e.g., be added to 3GPP TS 24.501 in Table 9.11.3.2.1. An example of Table 9.11.3.2.1 with a 5GMM cause value to indicate disaster condition added in underlined bold face type denoted “Disaster Condition” is provided below.
The network node 100 in this disclosure includes but is not limited to: a NodeB in wideband code division multiple access (WCDMA) system, an evolutional Node B (eNB) or an evolved NodeB (eNodeB) in LTE systems, or a relay node or an access point, or an in-vehicle device, a wearable device, or a gNB in the fifth generation (5G) networks.
Further, the network node 100 herein may be denoted as a radio network access node, an access network access node, an access point, or a base station, e.g. a radio base station (RBS), which in some networks may be referred to as transmitter, “gNB”, “gNodeB”, “eNB”, “eNodeB”, “NodeB” or “B node”, depending on the technology and terminology used. The radio network access nodes may be of different classes such as e.g. macro eNodeB, home eNodeB or pico base station, based on transmission power and thereby also cell size. The radio network access node can be a station (STA), which is any device that contains an IEEE 802.11-conformant MAC and PHY interface to the wireless medium. The radio network access node may also be a base station corresponding to the 5G wireless systems.
However, the network node 100 may also be a node of a core network. The network node 100 may e.g. be AMF as previously mentioned but may also be a session management function (SMF) or a policy control function (PCF).
The client device 300 in this disclosure includes but is not limited to: a UE such as a smart phone, a cellular phone, a cordless phone, a session initiation protocol (SIP) phone, a wireless local loop (WLL) station, a personal digital assistant (PDA), a handheld device having a wireless communication function, a computing device or another processing device connected to a wireless modem, an in-vehicle device, a wearable device, an integrated access and backhaul node (IAB) such as mobile car or equipment installed in a car, a drone, a device-to-device (D2D) device, a wireless camera, a mobile station, an access terminal, an user unit, a wireless communication device, a station of wireless local access network (WLAN), a wireless enabled tablet computer, a laptop-embedded equipment, an universal serial bus (USB) dongle, a wireless customer-premises equipment (CPE), and/or a chipset. In an Internet of things (IOT) scenario, the client device 300 may represent a machine or another device or chipset which performs communication with another wireless device and/or a network equipment.
The UE may further be referred to as a mobile telephone, a cellular telephone, a computer tablet or laptop with wireless capability. The UE in this context may e.g. be portable, pocket-storable, hand-held, computer-comprised, or vehicle-mounted mobile device, enabled to communicate voice and/or data, via the radio access network, with another entity, such as another receiver or a server. The UE can be a station (STA), which is any device that contains an IEEE 802.11-conformant media access control (MAC) and physical layer (PHY) interface to the wireless medium (WM). The UE may also be configured for communication in 3GPP related LTE and LTE-Advanced, in WiMAX and its evolution, and in fifth generation wireless technologies, such as NR.
Furthermore, any method according to one or more embodiments may be implemented in a computer program, having code means, which when run by processing means causes the processing means to execute the steps of the method. The computer program is included in a computer readable medium of a computer program product. The computer readable medium may comprise essentially any memory, such as a read-only memory (ROM), a programmable read-only memory (PROM), an erasable PROM (EPROM), a flash memory, an electrically erasable PROM (EEPROM), or a hard disk drive.
Moreover, it is realized by the skilled person that embodiments of the network node 100 and the client device 300 comprises the necessary communication capabilities in the form of e.g., functions, means, units, elements, etc., for performing the solution. Examples of other such means, units, elements and functions are: processors, memory, buffers, control logic, encoders, decoders, rate matchers, de-rate matchers, mapping units, multipliers, decision units, selecting units, switches, interleavers, de-interleavers, modulators, demodulators, inputs, outputs, antennas, amplifiers, receiver units, transmitter units, DSPs, MSDs, TCM encoder, TCM decoder, power supply units, power feeders, communication interfaces, communication protocols, etc. which are suitably arranged together for performing the solution.
Especially, the processor(s) of the network node 100 and the client device 300 may comprise, e.g., one or more instances of a central processing unit (CPU), a processing unit, a processing circuit, a processor, an application specific integrated circuit (ASIC), a microprocessor, or other processing logic that may interpret and execute instructions. The expression “processor” may thus represent a processing circuitry comprising a plurality of processing circuits, such as, e.g., any, some or all of the ones mentioned above. The processing circuitry may further perform data processing functions for inputting, outputting, and processing of data comprising data buffering and device control functions, such as call processing control, user interface control, or the like.
Finally, it should be understood that the present disclosure is not limited to the embodiments described above, but also relates to and incorporates all embodiments within the scope of the appended independent claims.
This application is a continuation of International Application No. PCT/CN2021/072297, filed on Jan. 15, 2021, the disclosure of which is hereby incorporated by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2021/072297 | Jan 2021 | WO |
| Child | 18328152 | US |
