Patent Publication Number: US-2022225447-A1

Title: Handling of Radio Resource Between Terminal Devices

Description:
TECHNICAL FIELD 
     Embodiments presented herein relate to a method, a first terminal device, a computer program, and a computer program product for requesting radio resources from a second terminal device. Further embodiments presented herein relate to a method, a second terminal device, a computer program, and a computer program product for granting radio resources to a first terminal device. Further embodiments presented herein relate to a method, a network node, a computer program, and a computer program product for handling radio resources between a first terminal device and a second terminal device. 
     BACKGROUND 
     In communications networks, there may be a challenge to obtain good performance and capacity for a given communications protocol, its parameters and the physical environment in which the communications network is deployed. 
     For example, one parameter in providing good performance and capacity for a given communications protocol in a communications network is resource scheduling. 
     Resource handling is commonly handled by the scheduler located in the radio access network node on the network side. The scheduler is configured to apply certain principles to divide radio resources (bandwidth, time slots, etc.) between terminal devices in a cell served by the radio access network node. The scheduler might further be configured to apply multi-cell scheduling policies to balance and mitigate interference and load variations over larger areas than a single cell and in situation where terminal devices not only in its own cell benefit from a jointly optimized resource dispatching approach. 
     One scheduling principle is Round Robin where the served terminal devices are scheduled according a given queue order, with the constraint of scheduling equal time and resources for each individual terminal device in the queue. Other scheduling mechanisms might consider weight factors and/or different priority levels as assigned to the individual terminal devices as well as the amount of data in transmit buffers and/or radio conditions for each individual terminal device when allocating the resources among the terminal devices. 
     Despite this, there are few means for an individual terminal device to impact to what extent the scheduler assigns resources to it. 
     Hence, there is still a need for an improved scheduling of terminal devices in a communications network. 
     SUMMARY 
     An object of embodiments herein is to provide mechanisms enabling efficient scheduling of terminal devices in a communications network. 
     According to a first aspect there is presented a method for requesting radio resources from a second terminal device. The method is performed by a first terminal device. The method comprises identifying an increasing need for use of radio resources. The method comprises transmitting, via a sidelink to the second terminal device, a request for using radio resources allocated to the second terminal device. The method comprises receiving, via the sidelink, a response from the second terminal device. The response pertains to whether the second terminal device has granted the first terminal device to use at least some of the requested radio resources or not. The method comprises providing, towards a network node serving the first terminal device, a notification of that the first terminal device has requested the radio resources from the second terminal device and/or of that the second terminal device has granted the first terminal device to use at least some of the requested radio resources. 
     According to a second aspect there is presented a first terminal device for requesting radio resources from a second terminal device. The first terminal device comprises processing circuitry. The processing circuitry is configured to cause the first terminal device to identify an increasing need for use of radio resources. The processing circuitry is configured to cause the first terminal device to transmit, via a sidelink to the second terminal device, a request for using radio resources allocated to the second terminal device. The processing circuitry is configured to cause the first terminal device to receive, via the sidelink, a response from the second terminal device. The response pertains to whether the second terminal device has granted the first terminal device to use at least some of the requested radio resources or not. The processing circuitry is configured to cause the first terminal device to provide, towards a network node serving the first terminal device, a notification of that the first terminal device has requested the radio resources from the second terminal device and/or of that the second terminal device has granted the first terminal device to use at least some of the requested radio resources. 
     According to a third aspect there is presented a computer program for requesting radio resources from a second terminal device. The computer program comprises computer program code which, when run on processing circuitry of a first terminal device, causes the first terminal device to perform a method according to the first aspect. 
     According to a fourth aspect there is presented a method for granting radio resources to a first terminal device. The method is performed by a second terminal device. The method comprises receiving, via a sidelink to the first terminal device, a request for the first terminal device to use radio resources allocated to the second terminal device. The method comprises transmitting, via the sidelink, a response to the first terminal device. The response pertains to whether the second terminal device has granted the first terminal device to use at least some of the requested radio resources or not. The method comprises providing, towards a network node serving the second terminal device, a notification of that the first terminal device has requested the radio resources from the second terminal device and/or of that the second terminal device has granted the first terminal device to use at least some of the requested radio resources. 
     According to a fifth aspect there is presented a second terminal device for granting radio resources to a first terminal device. The second terminal device comprises processing circuitry. The processing circuitry is configured to cause the second terminal device to receive, via a sidelink to the first terminal device, a request for the first terminal device to use radio resources allocated to the second terminal device. The processing circuitry is configured to cause the second terminal device to transmit, via the sidelink, a response to the first terminal device. The response pertains to whether the second terminal device has granted the first terminal device to use at least some of the requested radio resources or not. The processing circuitry is configured to cause the second terminal device to provide, towards a network node serving the second terminal device, a notification of that the first terminal device has requested the radio resources from the second terminal device and/or of that the second terminal device has granted the first terminal device to use at least some of the requested radio resources. 
     According to a sixth aspect there is presented a computer program for granting radio resources to a first terminal device. The computer program comprises computer program code which, when run on processing circuitry of a second terminal device, causes the second terminal device to perform a method according to the fourth aspect. 
     According to a seventh aspect there is presented a method for handling radio resources between a first terminal device and a second terminal device. The method is performed by a network node. The method comprises obtaining, from a least one of the first terminal device served by the network node and the second terminal device served by the network node, a notification of that the first terminal device has requested radio resources from the second terminal device where the radio resources have been allocated to the second terminal device, and/or of that the second terminal device has granted the first terminal device to use at least some of the requested radio resources. The method comprises transmitting, to at least one of the first terminal device and the second terminal device, a decision pertaining to whether the network node has accepted the at least some of the requested radio resources to be granted the first terminal device or not. 
     According to an eight aspect there is presented a network node for handling radio resources between a first terminal and a second terminal device. The network node comprises processing circuitry. The processing circuitry is configured to cause the network node to obtain, from a least one of the first terminal device served by the network node and the second terminal device served by the network node, a notification of that the first terminal device has requested radio resources from the second terminal device where the radio resources have been allocated to the second terminal device, and/or of that the second terminal device has granted the first terminal device to use at least some of the requested radio resources. The processing circuitry is configured to cause the network node to transmit, to at least one of the first terminal device and the second terminal device, a decision pertaining to whether the network node has accepted the at least some of the requested radio resources to be granted the first terminal device or not. 
     According to a tenth aspect there is presented a computer program for handling radio resources between a first terminal device and a second terminal device, the computer program comprising computer program code which, when run on processing circuitry of a network node, causes the network node to perform a method according to the seventh aspect. 
     According to an eleventh aspect there is presented a computer program product comprising a computer program according to at least one of the third aspect, the sixth aspect, and the tenth aspect and a computer readable storage medium on which the computer program is stored. The computer readable storage medium can be a non-transitory computer readable storage medium. 
     Advantageously these methods, these first terminal devices, these second terminal devices, these network nodes, these computer programs, and this computer program product enable efficient scheduling of terminal devices in a communications network. 
     Advantageously these methods, these first terminal devices, these second terminal devices, these network nodes, these computer programs, and this computer program product enable cell capacity, as given by the radio resources, to be traded between different terminal devices in a communications network. 
     In turn, this enables efficient utilization of available radio resource in the communications network. 
     In turn, this enables a terminal device to obtain more radio resources than given by the scheduling policy followed by the network node. 
     Advantageously these methods, these first terminal devices, these second terminal devices, these network nodes, these computer programs, and this computer program product enable the scheduling of radio resources to a terminal device to be adapter faster than if the scheduling were to be updated by means of a quality of service (QoS) policy update and/or change of subscription policy. 
     Other objectives, features and advantages of the enclosed embodiments will be apparent from the following detailed disclosure, from the attached dependent claims as well as from the drawings. 
     Generally, all terms used in the claims are to be interpreted according to their ordinary meaning in the technical field, unless explicitly defined otherwise herein. All references to “a/an/the element, apparatus, component, means, module, step, etc.” are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, module, step, etc., unless explicitly stated otherwise. The steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The inventive concept is now described, by way of example, with reference to the accompanying drawings, in which: 
         FIGS. 1 and 2  are schematic diagrams illustrating a communications network according to embodiments; 
         FIGS. 3, 4, and 5  are flowcharts of methods according to embodiments; 
         FIG. 6  is a signaling diagram of a method according to an embodiment; 
         FIG. 7  is a schematic diagram showing functional units of a terminal device according to an embodiment; 
         FIG. 8  is a schematic diagram showing functional modules of a terminal device according to an embodiment; 
         FIG. 9  is a schematic diagram showing functional units of a network node according to an embodiment; 
         FIG. 10  is a schematic diagram showing functional modules of a network node according to an embodiment; and 
         FIG. 11  shows one example of a computer program product comprising computer readable means according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     The inventive concept will now be described more fully hereinafter with reference to the accompanying drawings, in which certain embodiments of the inventive concept are shown. This inventive concept may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of the inventive concept to those skilled in the art. Like numbers refer to like elements throughout the description. Any step or feature illustrated by dashed lines should be regarded as optional. 
     As disclosed above, there is a need for an improved scheduling of terminal devices in a communications network. 
     In more detail, there are currently no means for terminal devices to initiate trade, or redistribution, of their already scheduled radio resources. In a scenario where a terminal device has a need for extra radio resource within certain hours, etc., and another terminal device in the same cell has scheduled radio resources to spare for the same certain hours, there is currently no means for the radio resources to be traded, or redistributed, among these two terminal devices (optionally exchanging some sort of payment/remuneration). 
     Although QoS schemes seemingly are designed for such scenarios and thus how this matter should be addressed, i.e. where there are QoS models that assign different scheduling weights and priorities to different terminal devices depending on their current buffer status and radio environment, given a certain subscription, scheduling in the above scenario is not easily executed. 
       FIG. 1  is a schematic diagram illustrating a communications network bow where embodiments presented herein can be applied. The communications networks bow, could be a third generation (3G) telecommunications network, a fourth generation (4G) telecommunications network, or a fifth (5G) telecommunications network, or any combination thereof, and support any 3GPP telecommunications standard, where applicable. 
     The communications network bow comprises a radio access network  110 , a core network  120 , and a service network  130 , which are interconnected with each other. In turn, the radio access network  110  comprises a radio access network node  140  configured to provides network access to terminal devices  200   a,    200   b  within the cell served by the radio access network node  140 , thus enabling the terminal device  200   a,    200   b  to communicate with over a wireless link  150   a,    150   b.  The terminal devices  200   a,    200   b  are thereby enabled to, via the radio access network node  140 , access services of, and exchange data with, the service network  130 . 
     Operation of the radio access network node  140  is controlled by a network node  300 . The network node  300  could be part of, integrated with, collocated with, or physically separated from, the radio access network node  140 . The terminal devices  200   a,    200   b  are further configured to communicate directly with each other over a wireless sidelink  160 . As will be further disclosed below, the wireless sidelink  160  is facilitated by a proximity-based services (ProSe) as provided by a ProSe server  170 . 
     Examples of radio access network nodes  140  are radio base stations, base transceiver stations, Node Bs (NBs), evolved Node Bs (eNBs), gNBs, access points, and access nodes, and backhaul nodes. Examples of terminal devices  200   a,    200   b  are wireless devices, mobile stations, mobile phones, handsets, wireless local loop phones, user equipment (UE), smartphones, laptop computers, tablet computers, network equipped sensors, network equipped vehicles, machine type communication (MTC) devices, and so-called Internet of Things (IoT) devices. As the skilled person the communications network  100   a  might comprise a plurality of radio access network nodes  140  providing network access to a plurality of terminal devices  200   a,    200   b.    
     Hereinafter, terminal device  200   a  is denoted a first terminal device and terminal device  200   b  is denoted a second terminal device. However, this notation is for simplifying the description and does not necessarily impose a hierarchical relation between these terminal devices  200   a,    200   b.    
       FIG. 2  is a schematic diagram illustrating a communications network  100   b  showing the communications interfaces between the entities of the communications network  100   a  of  FIG. 1 . The first terminal device  200   a  and the second terminal device  200   b  communicate with each other over communication interface PC5, the first terminal device  200   a  and the second terminal device  200   b  communicate with the radio access network (including the radio access network node  140  and possibly the network node  300 ) over communication interface Uu, and the first terminal device  200   a  and the second terminal device  200   b  communicate with the ProSe server  170  over communication interface PC3. That is, the sidelink  160  is established over the PC5 interface, and the wireless links  150   a,    150   b  are established over the Uu interface. For 3GPP Release 12 and onwards, the PC5 interface is a one-to-many communication interface, i.e. it is specified for group communication. From a higher protocol layer perspective (e.g., higher layer than protocol layer 1; the physical layer), this is reflected in the assignment of destination identities (IDs), which according to the ProSe functionality are always group IDs. The Internet Protocol (IP) address of the ProSe server  170  might be preconfigured (hard-coded) in the terminal device  200   a,    200   b.  Alternatively, the terminal device  200   a,    200   b  identify the IP address of the ProSe server  170  via a domain name server (DNS) look-up. To contact the ProSe server  170  the terminal device  200   a,    200   b  have to establish a radio resource control (RRC) connection with the network node over the Uu interface. The radio access network (including the radio access network node  140  and possibly the network node  300 ) communicates with the core network  120  (possibly including the network node  300 ) over communication interface S1, and the core network  120  (possibly including the network node  300 ) communicates with the ProSe server  170  over communication interface PC4. As the skilled person understands, these are just examples of communication interfaces and the entities of  FIGS. 1 and 2  might be configured to communicate with each other using other communication interfaces, depending on the actual implementation of the communications network  100   a,    100   b,  for example with regards to which telecommunications standard is to be supported (e.g., Long Term Evolution (LTE), New Radio (NR), etc.). 
     Among a group of terminal devices  200   a,    200   b  served by the network node  300 , although the network node  300  does not consider the need of the individual terminal devices  200   a,    200   b  other than fulfilling a configured scheduling policy, there might be a need for some of the served terminal devices  200   a,    200   b  that requires the terminal device to use more than its scheduled radio resources. 
     To make this feasible among the group of terminal devices  200   a,    200   b,  it is according to the present disclosure proposed that at least two terminal devices  200   a,    200   b  perform a negotiation of radio resources over a sidelink  160 . 
     The communication over the sidelink  160  is an example of device to device (D2D) communication. D2D communication can be used to support ProSe. Typical applications range from public safety, traffic control/safety and commercial services like proximity based social networking, gaming, and advertisements for by-passers. The network node  300  indicates support of sidelink communication with the presence of system information block 18 (SIB18). 
     ProSe can be provided when terminal devices supporting such services are within direct communication capabilities range of each other. Examples of ProSe services are ProSe Direct Discovery (according to which terminal devices  200   a,    200   b  in lo proximity of each other are identified; for two terminal devices  200   a,    200   b  within cellular coverage it may also be used for other commercial purposes), and ProSe Direct Communication between two terminal devices. Radio resources from cellular traffic are reserved and used for this type of communication or enables communication in areas without cellular coverage. 
     In this context the sidelink  160  is used for ProSe Direct Discovery and Prose Direct communication between terminal devices  200   a,    200   b  and the sidelink  160  corresponds to the communication between two ProSe enabled terminal devices  200   a,    200   b.  The sidelink communication describes the channel structure consisting of Logical, Transport and physical channels over the air interface to realize a ProSe application (see, interface PC5 in  FIG. 2 ). 
     The embodiments disclosed herein relate to mechanisms for handling radio resources between a first terminal device  200   a  and a second terminal device  200   b.  In order to obtain such mechanisms there is provided a first terminal device  200   a,  a method performed by the first terminal device  200   a,  a computer program product comprising code, for example in the form of a computer program, that when run on processing circuitry of the first terminal device  200   a,  causes the first terminal device  200   a  to perform the method. In order to obtain such mechanisms there is further provided a second terminal device  200   b,  a method performed by the second terminal device  200   b,  and a computer program product comprising code, for example in the form of  30  a computer program, that when run on processing circuitry of the second terminal device  200   b,  causes the second terminal device  200   b  to perform the method. In order to obtain such mechanisms there is further provided a network node  300 , a method performed by the network node  300 , and a computer program product comprising code, for example in the form of a computer program, that when run on processing circuitry of the network node  300 , causes the network node  300  to perform the method. 
     Reference is now made to  FIG. 3  illustrating a method for requesting radio resources from a second terminal device  200   b  as performed by the first terminal device  200   a  according to an embodiment. 
     S 102 : The first terminal device  200   a  identifies an increasing need for use of radio resources. 
     In this respect, although a terminal device, such as the first terminal device  200   a,  itself might identify an increasing need for use of radio resources, the actual allocation, or scheduling, of radio resources for each terminal device  200   a,    200   b  is handled by the scheduler of the network node  300  serving the terminal devices  200   a,    200   b.  Examples of causes for the increasing need for use of radio resources will be given below. The first terminal device  200   a  then requests extra radio resource from a peer terminal device, exemplified by the second terminal device  200   b.    
     S 110 : The first terminal device  200   a  transmits, via a sidelink  160  to the second terminal device  200   b,  a request for using radio resources allocated to the second terminal device  200   b.    
     It is assumed that the second terminal device  200   b  responds to the first terminal device  200   a.    
     S 112 : The first terminal device  200   a  receives, via the sidelink  160 , a response from the second terminal device  200   b,  the response pertaining to whether the second terminal device  200   b  has granted the first terminal device  200   a  to use at least some of the requested radio resources or not. 
     A notification is then provided towards the network node  300  serving the first terminal device  200   a.    
     S 116 : The first terminal device  200   a  provides, towards a network node  300  serving the first terminal device  200   a,  a notification of that the first terminal device  200   a  has requested the radio resources from the second terminal device  200   b  and/or of that the second terminal device  200   b  has granted the first terminal device  200   a  to use at least some of the requested radio resources. 
     Different examples of how the notification might be provided towards the network node  300  will be provided below. 
     Embodiments relating to further details of requesting radio resources from a second terminal device  200   b  as performed by the first terminal device  200   a  will now be disclosed. 
     In some examples the sidelink  160  is established over interface PC5. 
     In some examples the radio resources are to be consumed by the first terminal device  200   a  for enabling cellular communication with the network node  300  serving the first terminal device  200   a.    
     There could be different causes for the increasing need for use of radio resources. In some examples the increasing need is caused by a comparatively large amount of uplink data to be transmitted by the first terminal device  200   a  towards the network node  300 . In some examples the increasing need is caused by a comparatively large amount of downlink data to be transmitted to the first terminal device  200   a  from the network node  300 . In some examples the increasing need is caused by a need for a comparatively high level of quality of service required by a certain network service which the first terminal device  200   a  is to use. There could be different network services where the large amount of data (uplink or downlink) and high level of quality of service is needed. One example of such a network service is mission critical (MC) services or other types of emergency, rescue, or investigation, services. 
     In some examples the increasing need for use of radio resources pertains to a certain amount of radio resources and/or a certain amount of time when the radio resources are needed for consumption by the first terminal device  200   a.  For example, the need could be specified in terms of a certain amount of physical resource blocks, symbols, bits, bandwidth, etc. 
     In some aspects the sidelink  160  is not already established when the first terminal device  200   a  identifies the increasing need for use of radio resources. The sidelink  160  then needs to be established before the request in S 110  is transmitted. According to an embodiment the first terminal device  200   a  is therefore configured to perform (optional) step S 104 : 
     S 104 : The first terminal device  200   a  transmits, to the network node  300 , a request to establish the sidelink  160 . 
     The first terminal device  200   a  would then receive a response from the network node  300  to establish the sidelink  160 . 
     In some aspects the request to establish the sidelink  160  includes information of the network service for which the radio resource are to be used by the terminal device  200 . Particularly, according to an embodiment, the request in S 104  to establish the sidelink  160  comprises an indication of which network service the increasing need for use of radio resources results from. 
     In some aspects the first terminal device  200   a  stores information of its previous sessions (e.g. considered sufficiently successful) so that reliable and fair second terminal devices  200   b  could be addressed first when seeking to establish the sidelink  160 . 
     The first terminal device  200   a  could then in its request to the serving network node  300  for a sidelink transmission include a request for the network node  300  to contact a list of preferred second terminal devices  200   b  for establishment of the sidelink  160 . In particular, according to an embodiment the first terminal device  200   a  is configured to perform (optional) step S 106 : 
     S 106 : The first terminal device  200   a  receives, from the network node  300 , an identifier of a set of candidate terminal devices to which the sidelink  160  can be established. The second terminal device  200   b  is then selected from the set of candidate terminal devices. 
     The identifier of the set of candidate terminal devices might be stored for future use, for example when a need for further radio resources is identified. In particular, according to an embodiment the first terminal device  200   a  is configured to perform (optional) step S 108 : 
     S 108 : The first terminal device  200   a  stores the identifier of the set of candidate terminal devices. 
     In other aspects the request includes a list of non-preferred second terminal devices  200   b  with which establishment of the sidelink is to, if possible, be avoided. The first terminal device  200   a  might store also this list such that when a need for further radio resources is identified it is avoided to establish a sidelink  160  to any of these non-preferred second terminal devices  200   b.    
     In some aspects the response in S 112  from the second terminal device  200   b  includes information of the amount of offered radio resources and/or of the time duration during which the offered radio resources might be used by the first terminal device  200   a.  In particular, according to an embodiment, the response from the second terminal device  200   b  comprises information of amount of the radio resources granted to the first terminal device  200   a  and/or for how long time the radio resources are granted to the first terminal device  200   a.    
     The notification in S 116  to the network node  300  might then include information of the amount of offered radio resources and/or of the time duration during which the offered radio resources might be used by the first terminal device  200   a.  In particular, according to an embodiment, the notification in S 116  provided towards the network node  300  comprises this information. 
     In some aspects the offer comprises details of payment/remuneration between the first terminal device  200   a  and the second terminal device  200   b.  The terminal devices  200   a,    200   b  could then reach an agreement on payment/renumeration with regards to an over-the-top application, or a peer-to-peer application for payment/renumeration, for the radio resources to be transferred from the second terminal device  200   b  to the first terminal device  200   a.  In particular, according to an embodiment, the request in S 110  comprises an offer for using radio resources allocated to the second terminal device  200   b  and the first terminal device  200   a  is configured to perform (optional) step S 114 : 
     S 114 : The first terminal device  200   a  transmits, via the sidelink  160 , a response to the second terminal device  200   b.  The response comprises at least a partial acceptance of the offer. 
     The notification in S 116  to the network node  300  might then include information of acceptance of the offer. In particular, according to an embodiment, the notification in S 116  provided towards the network node  300  comprises the at least partial acceptance of the offer. 
     In some aspects, payment/remuneration between the first terminal device  200   a  and the second terminal device  200   b  is additionally or alternatively handled via, or supervised by, the network node  300  and/or an Operational Support System (OSS) or Business Support System (BSS) in the communications network  100   a,    100   b.    
     There could be different ways for the first terminal device  200   a  to provide the notification in S 116 . Different aspects relating thereto will now be disclosed in detail. 
     According to a first aspect the notification is in S 116  provided by being transmitted directly to the network node  300 , without being transmitted via the second terminal device  200   b.  That is, according to an embodiment, the notification is in S 116  provided towards the network node  300  by being transmitted directly to the network node  300  from the first terminal device  200   a.    
     In this case the notification might comprise an encrypted, or otherwise protected, secret, such as a key, that is shared by the network node  300  and the second terminal device  200   b  but not known by the first terminal device  200   a  that will ensure the network node  300  that the second terminal device  200   b  has agreed to offer the requested radio resources to the first terminal device  200   a.  That is, according to an embodiment, the response from the second terminal device  200   b  comprises a protected secret shared by the network node  300  and the second terminal device  200   b  but not known by the first terminal device  200   a,  and the notification in S 116  comprises the protected secret. 
     According to a second aspect the notification is in S 116  provided by being transmitted to the network node  300  via the second terminal device  200   b.  That is, according to an embodiment the notification is in S 116  provided towards the network node  300  by being transmitted to the second terminal device  200   b  for forwarding therefrom to the network node  300 . 
     In this case the notification might comprise an encrypted, or otherwise protected, secret, such as a key, that is shared by the network node  300  and the first terminal device  200   a  but not known by the second terminal device  200   b  that will ensure the network node  300  that the first terminal device  200   a  has agreed to the offer of the requested radio resources as given by the second terminal device  200   b.  That is, according to an embodiment, the notification in S 116  comprises a protected secret shared by the network node  300  and the first terminal device  200   a  but not known by the second terminal device  200   b.    
     As will be further disclosed below, the network node  300  determines whether to accept or reject the at least some of the requested radio resources to be granted to the first terminal device  200   a.  Particularly, according to an embodiment the first terminal device  200   a  is configured to perform (optional) step S 118 : 
     S 118 : The first terminal device  200   a  receives, from the network node  300 , a decision pertaining to whether the network node  300  has accepted the at least some of the requested radio resources to be granted the first terminal device  200   a  or not. 
     The first terminal device  200   a  is then configured to act accordingly. Particularly, according to an embodiment the first terminal device  200   a  is configured to perform (optional) step S 120 : 
     S 120 : The first terminal device  200   a  consumes the at least some of the requested radio resources according to the decision. 
     Reference is now made to  FIG. 4  illustrating a method for granting radio resources to a first terminal device  200   a  as performed by the second terminal device  200   b  according to an embodiment. 
     As disclosed above, the first terminal device  200   a  requests extra radio resource from a peer terminal device, exemplified by the second terminal device  200   b.    
     S 204 : The second terminal device  200   b  receives, via a sidelink  160  to the first terminal device  200   a,  a request for the first terminal device  200   a  to use radio resources allocated to the second terminal device  200   b.    
     It is assumed that the second terminal device  200   b  responds to the first terminal device  200   a.    
     S 206 : The second terminal device  200   b  transmits, via the sidelink  160 , a response to the first terminal device  200   a.  The response pertains to whether the second terminal device  200   b  has granted the first terminal device  200   a  to use at least some of the requested radio resources or not. 
     A notification is then provided towards the network node  300  serving the second terminal device  200   b.    
     S 210 : The second terminal device  200   b  provides, towards a network node  300  serving the second terminal device  200   b,  a notification of that the first terminal device  200   a  has requested the radio resources from the second terminal device  200   b  and/or of that the second terminal device  200   b  has granted the first terminal device  200   a  to use at least some of the requested radio resources. 
     Different examples of how the notification might be provided towards the network node  300  will be provided below. 
     Embodiments relating to further details of granting radio resources to a first terminal device  200   a  as performed by the second terminal device  200   b  will now be disclosed. 
     In some examples the sidelink  160  is established over interface PC5. 
     As disclosed above, in some aspects the sidelink  160  is not already established when the first terminal device  200   a  identifies the increasing need for use of radio resources. The sidelink  160  then needs to be established before the request in S 204  is received. According to an embodiment the second terminal device  200   b  is therefore configured to perform (optional) step S 202 : 
     S 202 : The second terminal device  200   b  receives, from the network node  300 , a request to establish the sidelink  160 . 
     As disclosed above, in some aspects the response in S 206  from the second terminal device  200   b  includes information of the amount of offered radio resources and/or of the time duration during which the offered radio resources might be used by the first terminal device  200   a.  In particular, according the response to the first terminal device  200   a  comprises information of amount of the radio resources granted to the first terminal device  200   a  and/or for how long time the radio resources are granted to the first terminal device  200   a.    
     Further, the information of the amount of offered radio resources and/or of the time duration during which the offered radio resources might be used by the first terminal device  200   a  might be included in the notification in S 210  provided towards the network node  300 . That is, according to an embodiment, the notification in S 210  provided towards the network node  300  comprises this information. 
     As disclosed above, in some aspects the offer comprises details of payment/remuneration between the first terminal device  200   a  and the second terminal device  200   b.  Particularly, according to an embodiment, the request in S 204  comprises an offer for using radio resources allocated to the second terminal device  200   b  and the second terminal device  200   b  is configured to perform (optional) step S 208 : 
     S 208 : The second terminal device  200   b  receives, via the sidelink  160 , a response from the first terminal device  200   a.  The response comprises at least a partial acceptance of the offer. 
     The notification in S 210  to the network node  300  might then include information of acceptance of the offer. In particular, according to an embodiment, the notification in S 210  provided towards the network node  300  comprises the at least partial acceptance of the offer. 
     There could be different ways for the second terminal device  200   a  to provide the notification in S 210 . Different aspects relating thereto will now be disclosed in detail. 
     According to a first aspect the notification is in S 210  provided by being transmitted directly to the network node  300 , without being transmitted via the first terminal device  200   a.  That is, according to an embodiment, the notification is in S 210  provided towards the network node  300  by being transmitted directly to the network node  300  from the second terminal device  200   b.    
     In this case the notification might comprise an encrypted, or otherwise protected, secret, such as a key, that is shared by the network node  300  and the first terminal device  200   a  but not known by the second terminal device  200   b  that will ensure the network node  300  that the first terminal device  200   b  has agreed to the offer of the requested radio resources as given by the second terminal device  200   b.  That is, according to an embodiment, the response in S 206  from the first terminal device  200   a  comprises a protected secret shared by the network node  300  and the first terminal device  200   a  but not known by the second terminal device  200   b,  and the notification in S 210  comprises the protected secret. 
     According to a second aspect the notification is in S 210  provided by being transmitted to the network node  300  via the first terminal device  200   a.  That is, according to an embodiment the notification is in S 210  provided towards the network node  300  by being transmitted to the first terminal device  200   a  for forwarding therefrom to the network node  300 . 
     In this case the notification might comprise an encrypted, or otherwise protected, secret, such as a key, that is shared by the network node  300  and the second terminal device  200   b  but not known by the first terminal device  200   a  that will ensure the network node  300  that the second terminal device  200   b  has agreed to offer the requested radio resources to the first terminal device  200   a.  That is, according to an embodiment, the notification in S 210  comprises a protected secret shared by the network node  300  and the second terminal device  200   b  but not known by the first terminal device  200   a.    
     As will be further disclosed below, the network node  300  determines whether to accept or reject the at least some of the requested radio resources to be granted to the first terminal device  200   a.  Particularly, according to an embodiment the second terminal device  200   b  is configured to perform (optional) step S 212 : 
     S 212 : The second terminal device  200   b  receives, from the network node  300 , a decision pertaining to whether the network node  300  has accepted the at least some of the requested radio resources to be granted the first terminal device  200   a  or not. 
     The second terminal device  200   b  is then configured to act accordingly. Particularly, according to an embodiment the second terminal device  200   b  is configured to perform (optional) step S 214 : 
     S 214 : The second terminal device  200   b  refrains from consuming the at least some of the requested radio resources according to the decision. 
     Reference is now made to  FIG. 5  illustrating a method for handling radio resources between a first terminal device  200   a  and a second terminal device  200   b  as performed by the network node  300  according to an embodiment. 
     As disclosed above, a notification pertaining to whether the second terminal device  200   b  has granted the first terminal device  200   a  to use at least some of the requested radio resources or not is provided towards the network node  300 . 
     S 308 : The network node  300  obtains, from a least one of the first terminal device  200   a  served by the network node  300  and the second terminal device  200   b  served by the network node  300 , a notification of that the first terminal device  200   a  has requested radio resources from the second terminal device  200   b  where the radio resources have been allocated to the second terminal device  200   b,  and/or of that the second terminal device  200   b  has granted the first terminal device  200   a  to use at least some of the requested radio resources. 
     The network node  300  then responds with a decision regarding whether to accept or reject the at least some of the requested radio resources to be granted the first terminal device  200   a.    
     S 314 : The network node  300  transmits, to at least one of the first terminal device  200   a  and the second terminal device  200   b,  a decision pertaining to whether the network node  300  has accepted the at least some of the requested radio resources to be granted the first terminal device  200   a  or not. 
     Embodiments relating to further details of handling radio resources between a first terminal device  200   a  and a second terminal device  200   b  as performed by the network node  300  will now be disclosed. 
     As disclosed above, in some aspects the notification in S 308  might include information of acceptance of an offer. In particular, according to an embodiment the notification in S 308  comprises at least a partial acceptance of an offer of the first terminal device  200   a  for using radio resources allocated to the second terminal device  200   b.    
     As further disclosed above, in some aspects the notification in S 308  might include information of the amount of offered radio resources and/or of the time duration during which the offered radio resources might be used by the first terminal device  200   a.  In particular, according to an embodiment the notification in S 308  comprises information of amount of the radio resources granted to the first terminal device  200   a  and/or for how long time the radio resources are granted to the first terminal device  200   a.    
     As further disclosed above, in some aspects the sidelink  160  is not already established when the first terminal device  200   a  identifies the increasing need for use of radio resources. Particularly, according to an embodiment the network node  300  is configured to perform (optional) steps S 302 , S 304 : 
     S 302 : The network node  300  receives, from the first terminal device  200   a,  a request to establish the sidelink  160 ; and in response thereto: 
     S 304 : The network node  300  transmits, at least to the second terminal device  200   b,  a request to establish the sidelink  160 . 
     It is thus assumed that both the first terminal device  200   a  and the second terminal device  200   b  are requested, or even instructed or ordered, to establish the sidelink  160 . The request might further comprise instructions for the first terminal device  200   a  and the second terminal device  200   b  to not use uplink resources when transmission over the sidelink  160  is expected to be received. 
     As further disclosed above, in some aspects the request in S 302  to establish the sidelink  160  includes information of the network service for which the radio resource are to be used by the terminal device  200 . Particularly, according to an embodiment, the request to establish the sidelink  160  comprises an indication of which network service the increasing need for use of radio resources results from. 
     In some aspects the request in S 304  to establish the sidelink  160  is transmitted to more than one potential second terminal device. In particular, according to an embodiment, the request to establish the sidelink  160  is transmitted to a set of candidate terminal devices, and the network node  300  is configured to perform (optional) step S 306 : 
     S 306 : The network node  300  transmits, to the first terminal device  200   a,  an identifier of the set of candidate terminal devices. 
     There could be different ways for the network node  300  to determine which terminal devices to include in the set of candidate terminal devices. As will be further disclosed next, in some aspects the set of candidate terminal devices is based on their radio conditions, capabilities, and which network service the first terminal device  200   a  is to use, etc. Particularly, according to an embodiment, the set of candidate terminal devices is selected based on at least one of: their radio conditions, their capabilities, and which network service the requested radio resources are to be used by the first terminal device  200   a.  Further examples thereof will now be disclosed 
     In some aspects the network node  300  considers which second terminal devices  200   b  to inform of an incoming sidelink transmission over the PC5 interface by considering their corresponding weights in the scheduling process. 
     For example, the network node  300  could indicate the resource allocations of radio resources for the considered announcing and monitoring terminal devices by creating a list of potential second terminal devices  200   b  with respect to radio measures relevant for scheduling bandwidth prioritization, such as measurements of reference signal received power (RSRP), signal plus interference and noise ratio (SINR), modulation and coding scheme (MCS), channel quality indicator (CQI), transmission rank, etc. The network node  300  could then select a set of potential second terminal devices  200   b  among the terminal devices  200   b  present in the scheduling evaluations of the network node  300  such that the potential second terminal devices  200   b  will have an opportunity to provide radio resources to the first terminal device  200   a.  This could reduce the risk of a second terminal devices  200   b  beings selected that has little or no priority in the ongoing scheduling evaluations. 
     In some aspects the network node  300  considers which device category (such as UE category) the potential second terminal devices  200   b  belong to. For example, the network node  300  could consider their respective capabilities in terms of number of transmit/receive antennas, MCS, multiple input multiple output (MIMO) and transmission rank capability, QoS capabilities, maximum uplink/downlink throughput, etc. As an example, if the first terminal device  200   a  is of lower device category and/or has lower capabilities than the second terminal device  200   b,  only requested radio resources corresponding to the category and/or capabilities of the first terminal device  200   a  might be granted to the first terminal device  200   a,  which might enable surplus radio resources to be granted from the second terminal device  200   b  to a yet further terminal device, if needed. 
     In some aspects the request from the first terminal device  200   a  to establish the sidelink  160  comprises information about whether the requested radio resource are to be used for uplink communication or downlink communication. In some aspects the network node  300  thus considers what link direction (i.e., uplink or downlink) the requested radio resource are to be used for by the first terminal device  200   a.  The network node  300  could then select a set of potential second terminal devices  200   b  by considering those potential second terminal devices  200   b  present in the scheduling evaluations of the network node  300  such that the potential second terminal devices  200   b  will have an opportunity to provide radio resources to the first terminal device  200   a  in the link direction requested by the first terminal device  200   a.  This could reduce the risk of a second terminal devices  200   b  beings selected that has little or no radio resource available in the link direction requested by the first terminal device  200   a.    
     In some aspects the request from the first terminal device  200   a  to establish the sidelink  160  comprises an indication of which network service (such as mobile broadband, voice, streaming, etc.) the increasing need for use of radio resources results from. In some aspects the network node  300  thus considers what type of network service the requested radio resource are to be used for by the first terminal device  200   a.  The network node  300  could then select a set of potential second terminal devices  200   b  by considering those potential second terminal devices  200   b  present in the scheduling evaluations of the network node  300  such that the potential second terminal devices  200   b  will have an opportunity to provide radio resources to the first terminal device  200   a  capable of supporting the requested network service. This could reduce the risk of a second terminal devices  200   b  beings selected that has not enough amount of radio resource available for the network service to be used by the first terminal device  200   a.    
     As the skilled person understands the request from the first terminal device  200   a  might comprise an indication of two or more network services the increasing need for use of radio resources results from, and where the set of potential second terminal devices  200   b  is selected accordingly. 
     As the skilled person further understands, the above examples for selecting a set of potential second terminal devices  200   b  could be combined by the network node  300  considering two or more pieces of information (such as weights, category, link direction, network services). 
     In some aspects, the network node  300  determines whether to accept or reject the radio resources to be granted to the first terminal device  200   a.  In particular, according to a first embodiment the network node  300  is configured to perform (optional) step S 310 : 
     S 310 : The network node  300  accepts the at least some of the requested radio resources to be granted to the first terminal device  200   a;  or 
     In particular, according to a second embodiment the network node  300  is configured to perform (optional) step S 312 : 
     S 312 : The network node  300  rejects the at least some of the requested radio resources to be granted the first terminal device  200   a.    
     The decision is then transmitted as in above S 314 . 
     There could be different ways for the network node  300  to determine whether to accept (as in S 310 ) or reject (as in S 312 ) the at least some of the requested radio resources to be granted the first terminal device  200   a.    
     When the notification in S 308  is received (only) from the first terminal device  200   a,  the at least some of the requested radio resources are rejected to be granted to the first terminal device  200   a  when the notification fails to comprise a protected secret shared by the network node  300  and the second terminal device  200   b  but not known by the first terminal device  200   a.  The request might be granted, or at least be considered for further evaluation, when the notification comprises the protected secret. 
     When the notification in S 308  is received (only) from the second terminal device  200   b,  the at least some of the requested radio resources are rejected to be granted to the first terminal device  200   a  when the notification fails to comprise a protected secret shared by the network node  300  and the first terminal device  200   a  but not known by the second terminal device  200   b.  The request might be granted, or at least be considered for further evaluation, when the notification comprises the protected secret. 
     When a separate instance of the notification in S 308  is received from each of the first terminal device  200   a  and from the second terminal device  200   b,  the at least some of the requested radio resources are rejected to be granted the first terminal device  200   a  when the instances of the notification fail to match each other. The request might be granted, or at least be considered for further evaluation, when the instances of the notification match each other. 
     The further evaluation might relate to a policy decision for the first terminal device  200   a  and/or the second terminal device  200   b,  properties of a network subscription for the first terminal device  200   a  and/or the second terminal device  200   b,  etc. that might allow or not allow radio resources to be accepted from, or shared to, another terminal device. 
     One particular embodiment for handling radio resources between a first terminal device  200   a  and a second terminal device  200   b  based on at least some of the above disclosed embodiments will now be disclosed in detail with reference to the signaling diagram of  FIG. 6 . According to this embodiment, the first terminal device  200   a  sends via a D2D application a request to other D2D-capable terminal devices (as symbolized by the second terminal device  200   b ) in its vicinity (via the PC5 interface) to use a part of the radio resources (specified in term of duration, bandwidth, throughput, etc.) of these other terminal devices. The other part either accepts or rejects the request and information of this is sent to the first terminal device  200   a  and their serving network node  300 . 
     S 401 : First terminal device  200   a  considers its current cellular performance non-adequate (considering adequate radio quality but still poor throughput, i.e. due to high cell load) and decides to request potential other terminal devices in its vicinity to request a specified share of their radio resources, for example described in terms of a specified duration in time, bandwidth, application throughput, number of delivered bits, etc. 
     S 402 : First terminal device  200   a  requests its serving network node  300  for a sidelink transmission to contact other terminal devices  200   b  to request extra radio resources from them. 
     S 403   a,  S 403   b:  first terminal device  200   a  indicates resource allocations for the considered announcing and monitoring terminal devices. 
     S 404 : First terminal device  200   a  requests, via the sidelink, resources from the listening terminal devices (implicitly selected by the serving network node  300 ). For example, first terminal device  200   a  might provide a request with an offer for radio resource corresponding to specified duration in time, bandwidth, application throughput, number of delivered bits, etc. and optionally a renumeration offer for the radio resource. 
     S 405   a,  S 405   b:  First terminal device  200   a  responds to first terminal device  200   a  with either an acknowledgement (ACK) or a negative acknowledgement (NACK) to the request whereby first terminal device  200   a  in turn is prompted with an ACK/NACK, potentially including a partial agreement of the offer (in terms of offered radio resources, demand for renumeration, etc.), potentially including an alternative to the offer (in terms of offered radio resources, demand for renumeration, etc.). 
     S 406 : First terminal device  200   a  selects one offer and replies to second terminal device  200   b  with an agreement. 
     S 407 : First terminal device  200   a  sends a Requester Payment Agreed Message (R-PAM), including information of second terminal device  200   b  and terms, e.g. duration, of contract, etc. to the serving network node  300 . 
     S 408 : Second terminal device  200   b  sends a Provider Payment Agreed Message (P-PAM), including information of second terminal device  200   b  and duration of the contract, etc. to the serving network node  300 . 
     S 409 : Network node  300  checks presence and validity of both R-PAM and P-PAM. If both are found valid the network node  300  re-allocates scheduled radio resources of second terminal device  200   b  to first terminal device  200   a  for the time period agreed in the contract. If at least one is found invalid the network node  300  dismisses the request. With frequent mismatches between observed R-PAM and P-PAM, either first terminal device  200   a  or second terminal device  200   b  could be blocked/listed/black-listed/put-on-monitor for further considerations. 
     S 410 : Network node  300  releases second terminal device  200   b  from the contract after duration of contract time has passed (possibly in combination with some utilized measure of used radio resources). 
     S 411   a,  S 411   b:  Network node  300  informs first terminal device  200   a  and second terminal device  200   b  of the termination of the contract. 
       FIG. 7  schematically illustrates, in terms of a number of functional units, the components of a terminal device  200   a,    200   b  according to an embodiment. Processing circuitry  210  is provided using any combination of one or more of a suitable central processing unit (CPU), multiprocessor, microcontroller, digital signal processor (DSP), etc., capable of executing software instructions stored in a computer program product  1110   a  (as in  FIG. 11 ), e.g. in the form of a storage medium  230 . The processing circuitry  210  may further be provided as at least one application specific integrated circuit (ASIC), or field programmable gate array (FPGA). 
     Particularly, the processing circuitry  210  is configured to cause the terminal device  200   a,    200   b  to perform a set of operations, or steps, as disclosed above. For example, the storage medium  230  may store the set of operations, and the processing circuitry  210  may be configured to retrieve the set of operations from the storage medium  230  to cause the terminal device  200   a,    200   b  to perform the set of operations. The set of operations may be provided as a set of executable instructions. Thus the processing circuitry  210  is thereby arranged to execute methods as herein disclosed. 
     The storage medium  230  may also comprise persistent storage, which, for example, can be any single one or combination of magnetic memory, optical memory, solid state memory or even remotely mounted memory. 
     The terminal device  200   a,    200   b  may further comprise a communications interface  220  for communications with network node  300 , ProSe server  170 , other terminal devices  200   a,    200   b,  etc. in the communication network  100   a,    100   b.  As such the communications interface  220  may comprise one or more transmitters and receivers, comprising analogue and digital components. 
     The processing circuitry  210  controls the general operation of the terminal device  200   a,    200   b  e.g. by sending data and control signals to the communications interface  220  and the storage medium  230 , by receiving data and reports from the communications interface  220 , and by retrieving data and instructions from the storage medium  230 . Other components, as well as the related functionality, of the terminal device  200   a,    200   b  are omitted in order not to obscure the concepts presented herein. 
       FIG. 8  schematically illustrates, in terms of a number of functional modules, the components of a terminal device  200   a,    200   b  according to an embodiment. 
     When acting as a first terminal device  200   a,  the terminal device  200   a  comprises an identity module  210   a  configured to perform step S 102 , a transmit module  210   e  configured to perform step S 110 , a receive module  310   f  configured to perform step S 112 , and a provide module  310   h  configured to perform step S 116 . When acting as a first terminal device  200   a,  the terminal device  200   a  may further comprise a number of optional functional modules, such as any of a transmit module  210   b  configured to perform step S 104 , a receive module  210   c  configured to perform step S 106 , a store module  210   d  configured to perform step S 108 , a transmit module  210   g  configured to perform step S 114 , a receive module  210   i  configured to perform step S 118 , and a consume module  210   j  configured to perform step S 120 . 
     When acting as a second terminal device  200   b  the terminal device  200   b  comprises a receive module  210   l  configured to perform step S 204 , a transmit module  210   m  configured to perform step S 206 , and a provide module  210   o  configured to perform step S 210 . When acting as a second terminal device  200   b  the terminal device  200   b  may further comprise a number of optional functional modules, such as any of a receive module  210   k  configured to perform step S 202 , a receive module  210   n  configured to perform step S 208 , a receive module  210   p  configured to perform step S 212 , and a refrain module  210   q  configured to perform step S 214 . 
     In general terms, each functional module  210   a - 210   q  may be implemented in hardware or in software. Preferably, one or more or all functional modules  210   a - 210   q  may be implemented by the processing circuitry  210 , possibly in cooperation with the communications interface  220  and the storage medium  230 . The processing circuitry  210  may thus be arranged to from the storage medium  230  fetch instructions as provided by a functional module  210   a - 210   q  and to execute these instructions, thereby performing any steps of the terminal device  200   a,    200   b  as disclosed herein. 
       FIG. 9  schematically illustrates, in terms of a number of functional units, the components of a network node  300  according to an embodiment. Processing circuitry  410  is provided using any combination of one or more of a suitable central processing unit (CPU), multiprocessor, microcontroller, digital signal processor (DSP), etc., capable of executing software instructions stored in a computer program product  1110   c  (as in  FIG. 11 ), e.g. in the form of a storage medium  430 . The processing circuitry  410  may further be provided as at least one application specific integrated circuit (ASIC), or field programmable gate array (FPGA). 
     Particularly, the processing circuitry  410  is configured to cause the network node  300  to perform a set of operations, or steps, as disclosed above. For example, the storage medium  430  may store the set of operations, and the processing circuitry  410  may be configured to retrieve the set of operations from the storage medium  430  to cause the network node  300  to perform the set of operations. The set of operations may be provided as a set of executable instructions. Thus the processing circuitry  410  is thereby arranged to execute methods as herein disclosed. 
     The storage medium  330  may also comprise persistent storage, which, for example, can be any single one or combination of magnetic memory, optical memory, solid state memory or even remotely mounted memory. 
     The network node  300  may further comprise a communications interface  420  for communications with other entities, functions, nodes, servers, and devices of the communication networks  100   a,    100   b.  As such the communications interface  420  may comprise one or more transmitters and receivers, comprising analogue and digital components. 
     The processing circuitry  410  controls the general operation of the network node  300  e.g. by sending data and control signals to the communications interface  420  and the storage medium  430 , by receiving data and reports from the communications interface  420 , and by retrieving data and instructions from the storage medium  430 . Other components, as well as the related functionality, of the network node  300  are omitted in order not to obscure the concepts presented herein. 
       FIG. 10  schematically illustrates, in terms of a number of functional modules, the components of a network node  300  according to an embodiment. The network node  300  of  FIG. 10  comprises a number of functional modules; an obtain module  310   d  configured to perform step S 308 , and a transmit module  310   g  configured to perform step S 314 . The network node  300  of  FIG. 10  may further comprise a number of optional functional modules, such as any of a receive module  310   a  configured to perform step S 302 , a transmit module  310   b  configured to perform step S 304 , a transmit module  310   c  configured to perform step S 306 , an accept module  310   e  configured to perform step S 310 , and a reject module  310   f  configured to perform step S 312 . 
     In general terms, each functional module  310   a - 310   g  may be implemented in hardware or in software. Preferably, one or more or all functional modules  310   a - 310   g  may be implemented by the processing circuitry  410 , possibly in cooperation with the communications interface  420  and the storage medium  430 . The processing circuitry  410  may thus be arranged to from the storage medium  430  fetch instructions as provided by a functional module  310   a - 310   g  and to execute these instructions, thereby performing any steps of the network node  300  as disclosed herein. 
     The network node  300  may be provided as a standalone device or as a part of at least one further device. For example, the network node  300  may be provided in a node of the radio access network or in a node of the core network. Alternatively, functionality of the first terminal device  200   a  may be distributed between at least two devices, or nodes. These at least two nodes, or devices, may either be part of the same network part (such as the radio access network or the core network) or may be spread between at least two such network parts. In general terms, instructions that are required to be performed in real time may be performed in a device, or node, operatively closer to the cell than instructions that are not required to be performed in real time. In this respect, at least part of the network node  300  may reside in the radio access network, such as in the radio access network node. 
     Thus, a first portion of the instructions performed by the network node  300  may be executed in a first device, and a second portion of the of the instructions performed by the network node  300  may be executed in a second device; the herein disclosed embodiments are not limited to any particular number of devices on which the instructions performed by the network node  300  may be executed. Hence, the methods according to the herein disclosed embodiments are suitable to be performed by a network node  300  residing in a cloud computational environment. Therefore, although a single processing circuitry  310  is illustrated in  FIG. x9  the processing circuitry  310  may be distributed among a plurality of devices, or nodes. The same applies to the functional modules  310   a - 310   g  of  FIG. 30  and the computer programs  1120   c  of  FIG. 11 . 
       FIG. 11  shows one example of a computer program product  1110   a,    1110   b,    1110   c  comprising computer readable means  1130 . On this computer readable means  1130 , a computer program  1120   a  can be stored, which computer program  1120   a  can cause the processing circuitry  210  and thereto operatively coupled entities and devices, such as the communications interface  220  and the storage medium  230 , to execute methods according to embodiments described herein. The computer program  1120   a  and/or computer program product  1110   a  may thus provide means for performing any steps of the first terminal device  200   a  as herein disclosed. On this computer readable means  1130 , a computer program  1120   b  can be stored, which computer program  1120   b  can cause the processing circuitry  310  and thereto operatively coupled entities and devices, such as the communications interface  320  and the storage medium  330 , to execute methods according to embodiments described herein. The computer program  1120   b  and/or computer program product  1110   b  may thus provide means for performing any steps of the second terminal device  200   b  as herein disclosed. On this computer readable means  1130 , a computer program  1120   c  can be stored, which computer program  1120   c  can cause the processing circuitry  410  and thereto operatively coupled entities and devices, such as the communications interface  420  and the storage medium  430 , to execute methods according to embodiments described herein. The computer program  1120   c  and/or computer program product  1110   c  may thus provide means for performing any steps of the network node  300  as herein disclosed. 
     In the example of  FIG. 11 , the computer program product  1110   a,    1110   b,    1110   c  is illustrated as an optical disc, such as a CD (compact disc) or a DVD (digital versatile disc) or a Blu-Ray disc. The computer program product  1110   a,    1110   b,    1110   c  could also be embodied as a memory, such as a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), or an electrically erasable programmable read-only memory (EEPROM) and more particularly as a non-volatile storage medium of a device in an external memory such as a USB (Universal Serial Bus) memory or a Flash memory, such as a compact Flash memory. Thus, while the computer program  1120   a,    1120   b,    1120   c  is here schematically shown as a track on the depicted optical disk, the computer program  1120   a,    1120   b,    1120   c  can be stored in any way which is suitable for the computer program product  1110   a,    1110   b,    1110   c.    
     The inventive concept has mainly been described above with reference to a few embodiments. However, as is readily appreciated by a person skilled in the art, other embodiments than the ones disclosed above are equally possible within the scope of the inventive concept, as defined by the appended patent claims.