WO2014037042A1

WO2014037042A1 - Paging

Info

Publication number: WO2014037042A1
Application number: PCT/EP2012/067405
Authority: WO
Inventors: Mika Juhani NEVANDER
Original assignee: Nokia Siemens Networks Oy
Priority date: 2012-09-06
Filing date: 2012-09-06
Publication date: 2014-03-13

Abstract

The invention relates to an apparatus comprising: at least one processor and at least one memory including a computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: obtain a request to access a user device, and convey a paging request to all coupled nodes for forwarding to all tracking areas of each coupled node for accessing the user device in a node restoration procedure.

Description

Paging Field

The invention relates to apparatuses, methods, systems, computer programs, computer program products and computer-readable media. Background

The following description of background art may include insights, discoveries, understandings or disclosures, or associations together with disclosures not known to the relevant art prior to the present invention but provided by the invention. Some such contributions of the invention may be specifically pointed out below, whereas other such contributions of the invention will be apparent from their context.

In the long term evolution (LTE), a mobility management entity (MME) is a control element in the evolved packet core (EPC). Typically, the MME has a logically direct control plane (CP) connection to a user device which is used as the primary control channel between the user device and the network. Some of MME's responsibilities or functionalities are authentication and security, mobility management and managing subscription profile and service connectivity.

Brief description

According to an aspect of the present invention, there is provided an apparatus comprising: at least one processor and at least one memory including a computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: obtain a request to access a user device, and convey a paging request to all coupled nodes for forwarding to all tracking areas of each coupled node for accessing the user device in a node restoration procedure.

According to an aspect of the present invention, there is provided an apparatus comprising: at least one processor and at least one memory including a computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: obtain a paging request, wherein the paging request comprises identification on a public land mobile network the paging request concerns and/or a tracking area list left empty or marked as covering all of the tracking areas, and convey the paging request to tracking areas served under the identified public land mobile network or to all served tracking areas.

According to yet another aspect of the present invention, there is provided a method comprising: obtaining a request to access a user device, and conveying a paging request to all coupled nodes for forwarding to all tracking areas of each coupled node for accessing the user device in a node restoration procedure.

According to yet another aspect of the present invention, there is provided a method comprising: obtaining a paging request, wherein the paging request comprises identification on a public land mobile network the paging request concerns and/or a tracking area list left empty or marked as covering all of the tracking areas, and conveying the paging request to tracking areas served under the identified public land mobile network or to all served tracking areas.

According to yet another aspect of the present invention, there is provided an apparatus comprising: means for obtaining a request to access a user device, and means for conveying a paging request to all coupled nodes for forwarding to all tracking areas of each coupled node for accessing the user device in a node restoration procedure.

According to yet another aspect of the present invention, there is provided an apparatus comprising: means for obtaining a paging request, wherein the paging request comprises identification on a public land mobile network the paging request concerns and/or a tracking area list left empty or marked as covering all of the tracking areas, and means for conveying the paging request to tracking areas served under the identified public land mobile network or to all served tracking areas.

According to yet another aspect of the present invention, there is provided a computer program embodied on a computer-readable storage medium, the computer program comprising program code for controlling a process to execute a process, the process comprising: obtaining a request to access a user device, and conveying a paging request to all coupled nodes for forwarding to all tracking areas of each coupled node for accessing the user device in a node restoration procedure.

According to yet another aspect of the present invention, there is provided a computer program embodied on a computer-readable storage medium, the computer program comprising program code for controlling a process to execute a process, the process comprising: obtaining a paging request, wherein the paging request comprises identification on a public land mobile network the paging request concerns and/or a tracking area list left empty or marked as covering all of the tracking areas, and conveying the paging request to tracking areas served under the identified public land mobile network or to all served tracking areas. List of drawings

Some embodiments of the present invention are described below, by way of example only, with reference to the accompanying drawings, in which

Figure 1 illustrates an example of a system;

Figure 2 is a flow chart;

Figure 3 is another flow chart;

Figure 4 illustrates examples of apparatuses;

Figure 5 illustrates other examples of apparatuses.

Description of some embodiments

The following embodiments are only examples. Although the specification may refer to "an", "one", or "some" embodiment(s) in several locations, this does not necessarily mean that each such reference is to the same embodiment(s), or that the feature only applies to a single embodiment. Single features of different embodiments may also be combined to provide other embodiments. Furthermore, words "comprising" and "including" should be understood as not limiting the described embodiments to consist of only those features that have been mentioned and such embodiments may also contain also features, structures, units, modules etc. that have not been specifically mentioned.

Embodiments are applicable to any user device, such as a user terminal, as well as to any network element, relay node, server, node, corresponding component, and/or to any communication system or any combination of different communication systems that support required functionalities. The communication system may be a wireless communication system or a communication system utilizing both fixed networks and wireless networks. The protocols used, the specifications of communication systems, apparatuses, such as servers and user terminals, especially in wireless communication, develop rapidly. Such development may require extra changes to an embodiment. Therefore, all words and expressions should be interpreted broadly and they are intended to illustrate, not to restrict, embodiments.

In the following, different exemplifying embodiments will be described using, as an example of an access architecture to which the embodiments may be applied, a radio access architecture based on long term evolution advanced (LTE Advanced, LTE-A), that is based on orthogonal frequency multiplexed access (OFDMA) in a downlink and a single-carrier frequency-division multiple access (SC-FDMA) in an uplink, without restricting the embodiments to such an architecture, however. It is obvious for a person skilled in the art that the embodiments may also be applied to other kinds of communications networks having suitable means by adjusting parameters and procedures appropriately. Some examples of other options for suitable systems are the universal mobile telecommunications system (UMTS) radio access network (UTRAN or E-UTRAN), long term evolution (LTE, the same as E-UTRA), wireless local area network (WLAN or WiFi), worldwide interoperability for microwave access (WiMAX), Bluetooth®, personal communications services (PCS), ZigBee®, wideband code division multiple access (WCDMA), systems using ultra-wideband (UWB) technology, sensor networks, mobile ad-hoc networks (MANETs) and Internet Protocol multimedia subsystems (IMS). In an orthogonal frequency division multiplexing (OFDM) system, the available spectrum is divided into multiple orthogonal sub-carriers. In OFDM systems, the available bandwidth is divided into narrower sub-carriers and data is transmitted in parallel streams. Each OFDM symbol is a linear combination of signals on each of the subcarriers. Further, each OFDM symbol is preceded by a cyclic prefix (CP), which is used to decrease Inter-Symbol Interference. Unlike in OFDM, SC-FDMA subcarriers are not independently modulated.

Typically, a (e)NodeB ("e" stands for evolved) needs to know channel quality of each user device and/or the preferred precoding matrices (and/or other multiple input-multiple output (MIMO) specific feedback information, such as channel quantization) over the allocated sub-bands to schedule transmissions to user devices. Such required information is usually signalled to the (e)NodeB.

Figure 1 depicts examples of simplified system architectures only showing some elements and functional entities, all being logical units, whose implementation may differ from what is shown. The connections shown in Figure 1 are logical connections; the actual physical connections may be different. It is apparent to a person skilled in the art that the system typically comprises also other functions and structures than those shown in Figure 1 .

The embodiments are not, however, restricted to the system given as an example but a person skilled in the art may apply the solution to other communication systems provided with necessary properties.

Figure 1 shows a part of a radio access network based on E-UTRA, LTE, LTE-Advanced (LTE-A) or LTE/EPC (EPC = evolved packet core, EPC is enhancement of packet switched technology to cope with faster data rates and growth of Internet protocol traffic). E-UTRA is an air interface of LTE Release 8 (UTRA= UMTS terrestrial radio access, UMTS= universal mobile telecommunications system). Some advantages obtainable by LTE (or E- UTRA) are a possibility to use plug and play devices, and Frequency Division Duplex (FDD) and Time Division Duplex (TDD) in the same platform. Figure 1 shows user devices 100 and 102 configured to be in a wireless connection on one or more communication channels 104 and 106 in a cell with a (e)NodeB 108 providing the cell. The physical link from a user device to a (e)NodeB is called uplink or reverse link and the physical link from the NodeB to the user device is called downlink or forward link.

The NodeB, or advanced evolved node B (eNodeB, eNB) in LTE- Advanced, is a computing device configured to control the radio resources of communication system it is coupled to. The (e)NodeB may also be referred to as a base station, an access point or any other type of interfacing device including a relay station capable of operating in a wireless environment.

The (e)NodeB includes transceivers, for example. From the transceivers of the (e)NodeB, a connection is provided to an antenna unit that establishes bi-directional radio links to user devices. The antenna unit may comprise a plurality of antennas or antenna elements. The (e)NodeB is further connected to core network 1 10 (CN). Depending on the system, the counterpart on the CN side can be a serving gateway (S-GW, routing and forwarding user data packets), packet data network gateway (P-GW), for providing connectivity of user devices (UEs) to external packet data networks, or mobile management entity (MME), etc.

A communications system typically comprises more than one

(e)NodeB in which case the (e)NodeBs may also be configured to communicate with one another over links, wired or wireless, designed for the purpose. These links may be used for signalling purposes.

The communication system is also able to communicate with other networks, such as a public switched telephone network or the Internet 1 12. The communication network may also be able to support the usage of cloud services. It should be appreciated that (e)NodeBs or their functionalities may be implemented by using any node, host, server or access point etc. entity suitable for such a usage.

The user device (also called UE, user equipment, user terminal, terminal device, etc.) illustrates one type of an apparatus to which resources on the air interface are allocated and assigned, and thus any feature described herein with a user device may be implemented with a corresponding apparatus, such as a relay node. An example of such a relay node is a layer 3 relay (self-backhauling relay) towards the base station.

The user device typically refers to a portable computing device that includes wireless mobile communication devices operating with or without a subscriber identification module (SIM), including, but not limited to, the following types of devices: a mobile station (mobile phone), smartphone, personal digital assistant (PDA), handset, device using a wireless modem (alarm or measurement device, etc.), laptop and/or touch screen computer, tablet, game console, notebook, and multimedia device.

The user device (or in some embodiments a layer 3 relay node) is configured to perform one or more of user equipment functionalities. The user device may also be called a subscriber unit, mobile station, remote terminal, access terminal, user terminal or user equipment (UE) just to mention but a few names or apparatuses.

It should be understood that, in Figure 1 , user devices are depicted to include 2 antennas only for the sake of clarity. The number of reception and/or transmission antennas may naturally vary according to a current implementation.

Further, although the apparatuses have been depicted as single entities, different units, processors and/or memory units (not all shown in Figure 1 ) may be implemented.

It is obvious for a person skilled in the art that the depicted system is only an example of a part of a radio access system and in practise, the system may comprise a plurality of (e)NodeBs, the user device may have an access to a plurality of radio cells and the system may comprise also other apparatuses, such as physical layer relay nodes or other network elements, etc. At least one of the NodeBs or eNodeBs may be a Home(e)nodeB. Additionally, in a geographical area of a radio communication system a plurality of different kinds of radio cells as well as a plurality of radio cells may be provided. Radio cells may be macro cells (or umbrella cells) which are large cells, usually having a diameter of up to tens of kilometres, or smaller cells such as micro-, femto- or picocells. The (e)NodeBs of Figure 1 may provide any kind of these cells. A cellular radio system may be implemented as a multilayer network including several kinds of cells. Typically, in multilayer networks, one node B provides one kind of a cell or cells, and thus a plurality of (e) Node Bs are required to provide such a network structure.

Recently for fulfilling the need for improving the deployment and performance of communication systems, the concept of "plug-and-play" (e)NodeBs has been introduced. Typically, a network which is able to use "plug-and-play" (e)Node Bs, includes, in addition to Home (e)NodeBs (H(e)nodeBs), a home node B gateway, or HNB-GW (not shown in Figure 1 ). A HNB Gateway (HNB-GW), which is typically installed within an operator's network may aggregate traffic from a large number of HNBs back to a core network.

One embodiment may be carried out by a device configured to operate as a mobility management entity (MME). The MME is a control element in the EPC. In practice, the MME may be a server located in operator's premises. Typically, the MME has a logically direct control plane (CP) connection to a user device which is used as the primary control channel between the user device and the network. Some of MME's responsibilities or functionalities are authentication and security, mobility management and managing subscription profile and service connectivity. The MME may also be provided as a cloud service.

In the mobility management, in general, an MME keeps track on the location of user devices in its service area. The MME requests resources from an (e)NodeB as well as from a serving gateway it selects for a user device. The MME tracks the user device's location either on the (e)NodeB level, when the user device is in an active state, or at the level of tracking area (TA) which is a group of (e)NodeBs, when the user device is in an idle mode. If data is received to be forwarded to a user device in the idle mode, the MME will be notified and it requests (e)NodeBs in a user device's tracking area to page the user device. The embodiment is suitable for paging in a node restoration procedure. A restoration procedure is usually needed when an MME reset has taken place and following procedures are initiated: a mobile terminated user data transmission and/or mobile terminated services requested by a mobile switching centre (MSC)/visitor location register (VLR). Thus, an MME may not always have information on user device's tracking area when it needs to carry out a paging procedure. When the MME receives a paging request for unknown users, the MME level paging may take place according to the Node Restoration Specification.

The embodiment starts in block 200 of Figure 2.

In block 202, a request to access a user device is obtained. A request to access a user device may take place, when a mobile switching centre (MSC)/visitor location register (VLR) or serving gateway contacts an MME that data to a certain user is provided, for example. In a node restoration procedure, the MME has been restarted and it has lost subscriber information. A serving gateway (S-GW) or a mobile switching centre (MSC)/visitor location register (VLR) may still have a subscriber bearer/ serving gateway association and therefore they may contact the MME.

In block 204, a paging request is conveyed to all coupled nodes for forwarding to all tracking areas of each coupled node for accessing the user device in a node restoration procedure.

In the node restoration procedure, typically, an MME has to carry out paging throughout all tracking areas, since is does not have the location information of user devices. In a normal paging procedure, an MME informs (e)NodeBs which tracking areas the paging at issue concerns. For making paging throughout all tracking areas, the MME has to list all tracking areas each (e)NodeB serves in the paging request. For the list, the MME has to search databases for obtaining information on served tracking areas. This may demand so much resources that the MME may fail, and typically again, since the node restoration procedure is usually carried out after a failure. This may lead to the loop of failures severely deteriorating performance of the system the MME serves. In this embodiment, however, the MME conveys a paging request to all (e)NodeBs coupled to it for they to forward the paging to all tracking areas they serve without making a database search and separately listing all tracking areas per each (e)NodeB. In this case, the tracking area list may still be conveyed along the paging request to (e)NodeBs involved, but it may be left empty or marked as covering "all" (that is to say covering all of the tracking areas), or it may not be conveyed at all. Another option is that the paging request comprises information on public land mobile networks (PLMNs) supported by the MME. This is suitable for the case wherein an (e)Node B is shared, that is it supports more than one PLMN. The paging request may be forwarded to the PLMN wherein the target tracking areas are served.

The embodiment ends in block 206. The embodiment is repeatable in many ways. One example is shown by arrow 208 in Figure 2.

Another embodiment may be carried out by a device configured to operate as a network apparatus, such as a server, (e)node or host. The embodiment may also be provided as a cloud service. The embodiment is suitable for forwarding a paging request.

The embodiment starts in block 300 of Figure 3.

In block 302, a paging request comprising identification on a public land mobile network the paging request concerns and/or comprising a tracking area list left empty or marked as covering all of the tracking areas is obtained.

In block 304, the paging request is forwarded to tracking areas served under the identified public land mobile network or to all served tracking areas.

A mobile management entity (MME) may convey a paging request to all (e)NodeBs coupled to it for they to forward the paging to all tracking areas they serve without making a database search and separately listing all tracking areas per each (e)NodeB. In this case, the tracking area list may still be conveyed along the paging request to (e)NodeBs involved, but it may be left empty or marked as covering "all" (that is to say covering all of the tracking areas), or it may not be conveyed at all. Another option is that the paging request comprises information on public land mobile networks (PLMNs) supported by the MME. This is suitable for the case wherein an (e)Node B is shared, that is it supports more than one PLMN. The paging request may be forwarded to the PLMN wherein the target tracking areas are served.

In one option, when an (e)NodeB obtains a paging request wherein a tracking area information (TAI) list is empty or marked to cover all tracking areas, it forwards the paging request to all tracking areas. Another option is that if the paging request comprises only a PLMN identification (identity) not tracking area identification, the (e)NodeB forwards the paging request to all tracking areas served in the PLMN area in question.

The embodiment ends in block 306. The embodiment is repeatable in many ways. One example is shown by arrow 308 in Figure 3.

The steps/points, signaling messages and related functions described above in Figures 2 and 3 are in no absolute chronological order, and some of the steps/points may be performed simultaneously or in an order differing from the given one. Other functions may also be executed between the steps/points or within the steps/points and other signaling messages sent between the illustrated messages. Some of the steps/points or part of the steps/points can also be left out or replaced by a corresponding step/point or part of the step/point.

It should be understood that conveying, broadcasting, signalling transmitting and/or receiving may herein mean preparing a data conveyance, broadcast, transmission and/or reception, preparing a message to be conveyed, broadcasted, signalled, transmitted and/or received, or physical transmission and/or reception itself, etc. on a case by case basis. The same principle may be applied to terms transmission and reception as well.

An embodiment provides an apparatus which may be a mobility management entity or another suitable apparatus capable to carry out processes described above in relation to Figure 2.

It should be appreciated that an apparatus may include or otherwise be in communication with a control unit, one or more processors or other entities capable of carrying out operations according to the embodiments described by means of Figure 2. It should be understood that each block of the flowchart of Figure 2 and any combination thereof may be implemented by various means or their combinations, such as hardware, software, firmware, one or more processors and/or circuitry.

Figure 4 illustrates a simplified block diagram of an apparatus according to an embodiment.

As an example of an apparatus according to an embodiment, it is shown apparatus 400, such as a node, including facilities in control unit 404 (including one or more processors, for example) to carry out functions of embodiments according to Figure 4. The facilities may be software, hardware or combinations thereof as described in further detail below.

In Figure 4, block 406 includes parts/units/modules needed for reception and transmission, usually called a radio front end, RF-parts, radio parts, radio head, etc.

Another example of apparatus 400 may include at least one processor 404 and at least one memory 402 including a computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: obtain a request to access a user device, and convey a paging request to all coupled nodes for forwarding to all tracking areas of each coupled node for accessing the user device in a node restoration procedure.

Yet another example of an apparatus comprises means 404 (406) for obtaining a request to access a user device, and means 404 (406) for conveying a paging request to all coupled nodes for forwarding to all tracking areas of each coupled node for accessing the user device in a node restoration procedure.

Yet another example of an apparatus comprises an obtainer configured to obtain a request to access a user device, and a conveying unit configured to convey a paging request to all coupled nodes for forwarding to all tracking areas of each coupled node for accessing the user device in a node restoration procedure.

It should be understood that the apparatuses may include or be coupled to other units or modules etc., such as radio parts or radio heads, used in or for transmission and/or reception. This is depicted in Figure 4 as optional block 406.

Although the apparatuses have been depicted as one entity in Figure 4, different modules and memory may be implemented in one or more physical or logical entities.

An embodiment provides an apparatus which may be a node, host, server or other suitable apparatus capable to carry out processes described above in relation to Figure 3.

It should be appreciated that an apparatus may include or otherwise be in communication with a control unit, one or more processors or other entities capable of carrying out operations according to the embodiments described by means of Figure 3. It should be understood that each block of the flowchart of Figure 3 and any combination thereof may be implemented by various means or their combinations, such as hardware, software, firmware, one or more processors and/or circuitry.

Figure 5 illustrates a simplified block diagram of an apparatus according to an embodiment.

As an example of an apparatus according to an embodiment, it is shown apparatus 500, including facilities in control unit 504 (including one or more processors, for example) to carry out functions of embodiments according to Figure 3. The facilities may be software, hardware or combinations thereof as described in further detail below.

In Figure 5, block 506 includes parts/units/modules needed for reception and transmission, usually called a radio front end, RF-parts, radio parts, radio head, etc.

Another example of apparatus 500 may include at least one processor 504 and at least one memory 502 including a computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to: obtain a paging request, wherein the paging request comprises identification on a public land mobile network the paging request concerns and/or a tracking area list left empty or marked as covering all of the tracking areas, and convey the paging request to tracking areas served under the identified public land mobile network or to all served tracking areas.

Yet another example of an apparatus comprises means 504 (506) for obtaining a paging request, wherein the paging request comprises identification on a public land mobile network the paging request concerns and/or a tracking area list left empty or marked as covering all of the tracking areas, and means 504 (506) for conveying the paging request to tracking areas served under the identified public land mobile network or to all served tracking areas.

Yet another example of an apparatus comprises an obtainer configured to obtain a paging request, wherein the paging request comprises identification on a public land mobile network the paging request concerns and/or a tracking area list left empty or marked as covering all of the tracking areas, and a conveying unit configured to convey the paging request to tracking areas served under the identified public land mobile network or to all served tracking areas.

It should be understood that the apparatuses may include or be coupled to other units or modules etc., such as radio parts or radio heads, used in or for transmission and/or reception. This is depicted in Figure 5 as optional block 506.

Although the apparatuses have been depicted as one entity in Figure 5, different modules and memory may be implemented in one or more physical or logical entities.

An apparatus may in general include at least one processor, controller or a unit designed for carrying out control functions operably coupled to at least one memory unit and to various interfaces. Further, the memory units may include volatile and/or non-volatile memory. The memory unit may store computer program code and/or operating systems, information, data, content or the like for the processor to perform operations according to embodiments. Each of the memory units may be a random access memory, hard drive, etc. The memory units may be at least partly removable and/or detachably operationally coupled to the apparatus. The memory may be of any type suitable for the current technical environment and it may be implemented using any suitable data storage technology, such as semiconductor-based technology, flash memory, magnetic and/or optical memory devices. The memory may be fixed or removable.

The apparatus may be, include or be associated with at least one software application, module, unit or entity configured as arithmetic operation, or as a program (including an added or updated software routine), executed by at least one operation processor. Programs, also called program products or computer programs, including software routines, applets and macros, may be stored in any apparatus-readable data storage medium and they include program instructions to perform particular tasks. Computer programs may be coded by a programming language, which may be a high-level programming language, such as objective-C, C, C++, C#, Java, etc., or a low-level programming language, such as a machine language, or an assembler.

Modifications and configurations required for implementing functionality of an embodiment may be performed as routines, which may be implemented as added or updated software routines, application circuits (ASIC) and/or programmable circuits. Further, software routines may be downloaded into an apparatus. The apparatus, such as a node device, or a corresponding component, may be configured as a computer or a microprocessor, such as single-chip computer element, or as a chipset, including at least a memory for providing storage capacity used for arithmetic operation and an operation processor for executing the arithmetic operation.

Embodiments provide computer programs embodied on a distribution medium, comprising program instructions which, when loaded into electronic apparatuses, constitute the apparatuses as explained above. The distribution medium may be a non-transitory medium.

Other embodiments provide computer programs embodied on a computer readable storage medium, configured to control a processor to perform embodiments of the methods described above. The computer readable storage medium may be a non-transitory medium. The computer program may be in source code form, object code form, or in some intermediate form, and it may be stored in some sort of carrier, distribution medium, or computer readable medium, which may be any entity or device capable of carrying the program. Such carriers include a record medium, computer memory, read-only memory, photoelectrical and/or electrical carrier signal, telecommunications signal, and software distribution package, for example. Depending on the processing power needed, the computer program may be executed in a single electronic digital computer or it may be distributed amongst a number of computers. The computer readable medium or computer readable storage medium may be a non-transitory medium.

The techniques described herein may be implemented by various means. For example, these techniques may be implemented in hardware (one or more devices), firmware (one or more devices), software (one or more modules), or combinations thereof. For a hardware implementation, the apparatus may be implemented within one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), processors, controllers, micro-controllers, microprocessors, digitally enhanced circuits, other electronic units designed to perform the functions described herein, or a combination thereof. For firmware or software, the implementation may be carried out through modules of at least one chip set (e.g., procedures, functions, and so on) that perform the functions described herein. The software codes may be stored in a memory unit and executed by processors. The memory unit may be implemented within the processor or externally to the processor. In the latter case it may be communicatively coupled to the processor via various means, as is known in the art. Additionally, the components of systems described herein may be rearranged and/or complimented by additional components in order to facilitate achieving the various aspects, etc., described with regard thereto, and they are not limited to the precise configurations set forth in the given figures, as will be appreciated by one skilled in the art. It will be obvious to a person skilled in the art that, as technology advances, the inventive concept may be implemented in various ways. The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.

Claims

1 . An apparatus comprising:

at least one processor and at least one memory including a computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to:

obtain a request to access a user device, and

convey a paging request to all coupled nodes for forwarding to all tracking areas of each coupled node for accessing the user device in a node restoration procedure.

2. The apparatus of claim 1 , wherein the node restoration procedure is carried out when a mobility management entity reset has taken place and following procedures are initiated: a mobile terminated user data transmission and/or mobile terminated services requested by a mobile switching centre (MSC)/visitor location register (VLR).

3. The apparatus of claim 1 or 2, wherein the paging request is conveyed without making a database search and separately listing all tracking areas per each of the coupled nodes.

4. The apparatus of any preceding claim, further comprising causing the apparatus to:

convey a tracking area list along the paging request, wherein the tracking area list is left empty or marked as covering all of the tracking areas.

5. The apparatus of any preceding claim, wherein the paging request further comprises information on supported public land mobile networks.

6. The apparatus of any preceding claim, the apparatus comprising a mobile management entity.

7. A computer program comprising program instructions which, when loaded into the apparatus, carry out the processes of any preceding claim 1 to 6.

8. An apparatus comprising:

obtain a paging request, wherein the paging request comprises identification on a public land mobile network the paging request concerns and/or a tracking area list left empty or marked as covering all of the tracking areas, and

convey the paging request to tracking areas served under the identified public land mobile network or to all served tracking areas.

9. The apparatus of claim 8, the apparatus comprising a host, node or server.

10. A computer program comprising program instructions which, when loaded into the apparatus, carry out the processes of claim 8.

1 1 . A method comprising:

obtaining a request to access a user device, and

conveying a paging request to all coupled nodes for forwarding to all tracking areas of each coupled node for accessing the user device in a node restoration procedure.

12. The method of claim 1 1 , wherein the node restoration procedure is carried out when a mobility management entity reset has taken place and following procedures are initiated: a mobile terminated user data transmission and/or mobile terminated services requested by a mobile switching centre (MSC)/visitor location register (VLR).

13. The method of claim 1 1 or 12, wherein the paging request is conveyed without making a database search and separately listing all tracking areas per each of the coupled nodes.

14. The method of any preceding claim 1 1 to 13, further comprising: conveying a tracking area list along the paging request, wherein the tracking area list is left empty or marked as covering all of the tracking areas.

15. The method of any preceding claim 1 1 to 14, wherein the paging request further comprises information on supported public land mobile networks.

16. An apparatus comprising means for carrying out the method according to any one of claims 1 1 to 15.

17. A method comprising:

obtaining a paging request, wherein the paging request comprises identification on a public land mobile network the paging request concerns and/or a tracking area list left empty or marked as covering all of the tracking areas, and

conveying the paging request to tracking areas served under the identified public land mobile network or to all served tracking areas.

18. An apparatus comprising means for carrying out the method according to claim 17.

19. A computer program embodied on a computer-readable storage medium, the computer program comprising program code for controlling a process to execute a process, the process comprising:

obtaining a request to access a user device, and

20. A computer program embodied on a computer-readable storage medium, the computer program comprising program code for controlling a process to execute a process, the process comprising:

obtaining a paging request, wherein the paging request comprises identification on a public land mobile network the paging request concerns and/or a tracking area list left empty or marked as covering all of the tracking areas, and conveying the paging request to tracking areas served under the identified public land mobile network or to all served tracking areas.