Technical Field The invention refers to a method and a scheduler in a wireless communication system for scheduling the sending of data on a data connection between a radio base station and a wireless device.

Background

Mobile networks, such as e.g. wireless communication systems, consists of many components that supports 3GPP (3 ^rd Generation Partnership Project) based networks, like HSPDA HSPA (High Speed Downlink Packet Access/High Speed Packet Access), LTE (Long Term Evolution) and now also 5G New Radio Access Networks, to serve many wireless devices simultaneously with high or low bitrate and with reasonable packet latency. One of the key components in such a network is the MAC (Medium Access Control) Scheduler which is located above the physical layer in the data link layer according to the IEEE 802 reference model. The MAC Scheduler assigns bandwidth resources or radio resource blocks to wireless devices and is responsible for deciding on how uplink and downlink channels are used by the radio base station of a wireless communication system, which may be an evolved Node B (eNodeB or eNB) in LTE, and the wireless devices in a cell served by said radio base station. It also enforces the necessary Quality of Service (QoS) for wireless device connections. QoS is a set of rules that come from the Policy and Charging Rules Function (PCRF) in the core network. These rules define priority, bit rate and latency requirements for different connections to the UE. They are usually based on the types of applications using the wireless device connection. For example, the QoS requirements for a VoLTE (Voice over LTE) call are different from those for checking the e-mail.

Fig. 1 discloses a typical set-up of a MAC Scheduler in a wireless communication network. In order to take its resource allocation decisions, the MAC Scheduler receives information, such as:

- QoS data from the PCRF: minimum guaranteed bandwidth, maximum allowed bandwidth, packet loss rates, relative priority of users/wireless devices, etc.,

- messages from the wireless devices regarding the radio channel quality, the strength or weakness of the radio signal, etc., - measurements from the radio base station radio receiver or the wireless device radio receiver on the physical layer (PHY) regarding radio channel quality, noise and interference, etc.,

- buffer status reports from the upper layers (RLC) and/or core network about how much data is queued up waiting for transmission,

- system requirements, such as high system throughput or low latency per bearer.

The MAC Scheduler takes this as input to its supported scheduling algorithms to initiate a scheduling decision in MAC multiplexing, such as:

- Round Robin: users are scheduled in circular order without any priority,

- Proportional Fairness: Consider channel quality of wireless devices along with how much throughput the wireless devices have received and balance that in its allocation decision,

- Delay based: wireless devices that are close to its packet delay requirements will receive a higher priority in the allocation decision,

- Maximum C/l: always assign resource blocks to the wireless device with the best channel quality.

As can be seen in Fig. 2, the MAC scheduler has control over the OFDM (Orthogonal Frequency- Division Multiplexing) modulation in the sense that it decides, according to information received from other LTE network components, how much bandwidth each UE receives at any given moment. In Fig. 2, the resource elements (sub-carriers) are represented on the frequency axis, while the sub-frames are represented on the time axis.

Hence a MAC Scheduler can be programmed to support one scheduling algorithm with many input parameters. The common way of implementing the possible contradicting user and system requirements is by a weight framework. Each parameter value is given a weight according to a weight function or weight curve, and in the resource allocation decision all weights are summarized or multiplied to find the wireless device with the highest weight, which then are allocated resources for upcoming transmission time interval (TTI)

Summary

It is an object of the present invention to improve the method in a MAC Scheduler with a more efficient technique for scheduling the transmission of data. This object is achieved by the independent claims. Advantageous embodiments are described in the dependent claims.

According to a first aspect, a method for scheduling the sending of data on a data connection between a radio base station and a wireless device is provided. The method comprising or triggering the steps of determining expected radio channel resources per data rate associated to said data connection, calculating, based on the expected radio channel resources per data rate, relative resource shares between said wireless device and at least another wireless device, served by said radio base station, and scheduling the data transmission on said data connection based on the relative resource shares.

According to a second aspect, a scheduler for scheduling the sending of data on a data connection between a radio base station and a wireless device is provided. The scheduler comprising a processor and a memory, said memory containing instructions executable by said processor, whereby said scheduler is operative to trigger or perform the steps of determining expected radio channel resources per data rate associated to said data connection, calculating, based on the expected radio channel resources per data rate, relative resource shares between said wireless device and at least another wireless device, served by said radio base station, and scheduling the data transmission on said data connection based on the relative resource shares.

According to a third aspect, a scheduler in a wireless communication system for scheduling the sending of data on a data connection between a radio base station and a wireless device is provided. The scheduler is configured to trigger or perform the steps of determining expected radio channel resources per data rate associated to said data connection, calculating, based on the expected radio channel resources per data rate, relative resource shares between said wireless device and at least another wireless device, served by said radio base station, and scheduling the data transmission on said data connection based on the relative resource shares.

The present invention also concerns computer programs comprising portions of software codes or instructions in order to implement the method as described above when operated by at least one respective processing unit of a user device and a recipient device. The computer program can be stored on a computer-readable medium. The computer-readable medium can be a permanent or rewritable memory within the user device or the recipient device or located externally. The respective computer program can also be transferred to the user device or recipient device for example via a cable or a wireless link as a sequence of signals.

Brief Description of the Figures

In the following, the invention will further be described with reference to exemplary embodiments illustrated in the figures, in which:

Fig. 1 shows a block diagram of a known set-up of a MAC Scheduler in a wireless communication system,

Fig. 2 shows a schematic illustration of a resource scheduling for uplink and downlink resources,

Fig. 3 shows an exemplary block diagram of a wireless communication network according to one embodiment,

Fig. 4 shows a flow diagram of a scheduling method according to one embodiment, Fig. 5 shows a flow diagram of a scheduling method according to a further embodiment, Fig. 6 shows a sequence diagram illustrating one embodiment of a scheduling method, Fig. 7 shows a block diagram of a scheduler according to one embodiment,

Fig. 8 shows a block diagram illustrating a scheduler according to another embodiment.

Detailed Description

In the below, for purposes of explanation and not limitation, specific details are set forth in order to provide a thorough understanding of the present invention. It will be apparent to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. For example, although the exemplary embodiments are described in connection with LTE standard terminology to illustrate the present invention, they are equally applicable to other kinds of mobile communication systems, like UMTS or 5G. Also, the invention may be practiced in any network to which mobile users may attach. For example, the present invention is applicable to, besides cellular networks, Local Area Networks (LANs), Wireless LANs (WLANs), or similar wireless networks, but also to wireline networks such as, for example, the intranet of a company or the Internet. Within the context of the present application, the term "wireless device" refers to a device for instance used by a person for his or her personal communication. It can be a telephone type of device, for example a telephone or a SIP phone, cellular telephone, a mobile station, cordless phone, or a personal digital assistant type of device like laptop, notebook, notepad equipped with a wireless data connection. The wireless device may also be associated with non-humans like animals, plants, or even machines.

Within the context of the present application, the term "wireless communication network" may particularly denote a collection of nodes or entities, related transport links, and associated management needed for running a service, for example a telephony service or a packet transport service. Depending on the service, different node types or entities may be utilized to realize the service. A network operator owns the communication network and offers the implemented services to its subscribers. Typical examples of a communication network are radio access network (such as 2G, GSM, 3G, WCDMA, CDMA, LTE, WLAN, Wi-Fi), mobile backhaul network, or core network such as IMS, CS Core, PS Core.

Within the context of the present application a transmission time interval (TTI) may particularly denote a duration of a transmission of data on a radio link between the wireless device and the radio base station. In LTE, the TTI is set to 1 ms. During each TTI the physical radio environment per wireless device shall be considered. Further, the Quality of Service requirements among the wireless devices should be prioritized during each TTI. Further, the wireless device shall be informed of allocated radio resources.

The illustration in the drawing is schematic. In different drawings, similar or identical elements are provided with the same reference signs or with reference signs which are different from one another in the first digit.

Fig. 3 shows an exemplary embodiment of a wireless communication network, comprising a radio base station 100 and two wireless devices A 200 and B 300. The wireless devices 200, 300 are named as "UE" (User Equipment) but they may also refer to other wireless devices as mentioned above. Data connections 210, 310 are established between both wireless devices 200, 300 and the radio base station 100. Within the context of the present application data connections 210, 310 may particularly denote bearers which are established between the radio base station 100 and the respective wireless devices 200, 300. The data connection 210, 310 may also particularly denote a flow or IP flow between the radio base station 100 and the respective wireless devices 200, 300.

According to the exemplary embodiment of Fig. 3, wireless device A 200 is located closer to the radio base station 100 than wireless device B 300. Due to this set up it might be possible that data connection 210 has a better radio connection with the radio base station 100 than data connection 310. This is depicted by a broader or smaller arrow between each wireless device 200, 300 and the radio base station 100. It may also be possible that each radio data connection 210, 310 is influenced by other parameters, like radio channel interferences or geographical setup.

According to one example embodiment, expected radio channel resources per data rate associated to data connections 210 and 310, which is needed to transmit data between radio base station 100 and wireless device A 200 / wireless device B 300 over said data connection is determined. Within the context of the present application the association of the expected radio channel resources per data rate to the data connection means that these resources are related or linked to the data connection. Within the context of the present application a resource may particularly denote a physical resource block according to Long Term Evolution, LTE, which occupies a given frequency range for a certain timeframe. In another example the resource may particularly denote a physical resource block in a Narrow-Band Internet-of-Things (NB-loT) scenario. It may also be possible to have multiple resources on a single resource block, e.g. by using code division multiplex or multi-user, MIMO. In other word, each connection 210, 310 has a different maximum data transmission rate or bandwidth. Therefore, for each connection 210, 310, a different expected radio channel resource for a fixed transmission rate (e.g. 1 Mbit/s) is determined. If e.g. the connection 210 is a good radio connection it is possible to transmit data with a channel coding with less redundancy. This results in less resources to be used to reach the same transmission rate. If the data rate has been fixed to a reference transmission rate, like 1 Mbit/s, the "costs" or expected number of required resources used for a transmission over a good connection with a fixed data rate is lower than for a transmission over a bad connection with higher interferences and the same fixed data rate.

The data transmission can be scheduled for uplink or downlink transmission. According to an example the data rate or bitrate for wireless device A 200 might be set as a reference value to 1 Mbit/s and the expected radio channel resource per data rate was determined as being 25% of all available radio channel resources of the radio base station 100. This means that, according to this example, wireless device A needs 25% of the available radio channel resources of the radio base station 100 to transmit data with a certain bitrate of 1 Mbit/s over the data connection 210. In the example of Fig. 2, the data connection 310 between wireless device B 300 and the radio base station 100 might have a higher expected radio channel resource per data rate. According to this example, the expected radio channel resource might be 50% of all available radio channel resources at a reference bitrate of 1 Mbit/s. This means that wireless device B 300 needs 50% of the radio resources of the radio base station 100 to transmit data over this data connection 310 with a bit rate of 1 Mbit/s.

The expected radio channel resource per data rate may be determined as a percentage value of total available resources at the radio base station 100, as shown above, or may be determined as a value which provides the number of resources needed per data rate. The data rate may particularly denote a bit rate or any other rate of data per timeframe. According to another embodiment the expected radio channel resources per data rate may be expressed in an inverse manner, namely how many data or bits can be transmitted on every resource at a reference bitrate of e.g. 1 Mbit/s.

The expected radio channel resources per data rate may be an expected average value and may be based on historical or previous transmissions. The information of previous used radio channel resources per data rate may be stored as history data in a memory and can be used to determine expected radio channel resources per data rate. Using historical data allows the execution of less measurement processes which reduces processing time and increases radio transmission capacity.

According to another embodiment the determination of expected radio channel resources per data rate may be based on measurements of the radio environment. The measurement may be measurement on radio environment from the wireless devices 200, 300 or may be measurements on radio environment from the radio base station 100, or both. These measurements of radio environment may be measured attenuations on a radio channel or may be measurements on the strength of pilot signals in a radio frame or anything else which may provide information about the quality of a radio connection. This allows a fast reaction on changes in the character of the radio channels due e.g. to movement of the wireless devices 200, 300 in relation to the radio base station 100. In another embodiment, the expected radio channel resources per data rate may be determined periodically. The periodic determination is done every timeslot in a consistent manner which allows a very consistent and predictable data flow. The periodicity may be correlated with a transmission time interval (TTI) for said wireless device. This results in one determined expected radio channel resources per data rate every TTI such that if a change in radio condition occurs, the resources can be distributed among the wireless devices in a very flexible manner and on short-term. In another embodiment, the expected radio channel resources per data rate are determined event triggered such that only in case of an event the determination step is executed. One example for an event may be the change of the quality of the data connection 210, 310 between the radio base station 100 and at least one of the wireless device 200 or the at least another wireless device 300. This will reduce processing time at the scheduler.

In a further step, relative resource shares between said wireless device and at least another wireless device, served by said radio base station is calculated. This calculation is based on the expected radio channel resources per data rate which has been determined before. In the example embodiment of Fig. 3, a relative resource share between wireless device wireless device A 200 and another wireless device B 300 is calculated. According to another embodiment, more than two wireless devices are served by the radio base station 100 - which results in a relative resource share calculation between all wireless devices. According to the embodiment of Fig. 3 and taking into account the determined expected radio channel resources per data rate a calculation of relative resources shares between both wireless devices 200, 300 is done. Further quality of service requirements and other fairness criteria must be taken into account to calculate the relative resource shares. Assuming that wireless device A 200 has a bitrate requirement of 2 Mbit/s and wireless device B has a bitrate requirement of 1 Mbit/s and further assuming the already determined expected radio channel resources per data rate of 25% for wireless device A and 50% for wireless device B with a common data rate of 1 Mbit/s the relative resource share may be calculated as allocating 50% (2 x 25%) to wireless device A 200 and 50% (1 x 50%) to wireless device B. In this rather simple example both QoS requirements are met so that both wireless devices 200, 300 can be served in a manner to fulfill all quality requirements. The relative resource share has been calculated as bitrate requirements times expected radio channel resources per data rate. Fig. 4 shows a flowchart for illustrating a method 400 which may be utilized for implementing the illustrated concepts in a scheduler of a wireless communication network. The method may be performed by a scheduler in an access node of the wireless communication network, which may be a cellular network, e.g., by a scheduler in a base station which is responsible for providing access of wireless communication devices to the cellular network. The scheduler is configured to trigger or perform in step 410 the determination of an expected radio channel resources per data rate associated to said data connection. The determined expected radio channel resources are needed to transmit data between said radio base station and said wireless device over said data connection. The scheduler is further configured to trigger or perform in a next step 420 the calculation of relative resource shares between said wireless device and at least another wireless device, served by said radio base station based on the expected radio channel resources per data rate. The scheduler is further configured to trigger or perform in a next step 430 the scheduling of the data transmission on said data connection based on the relative resource shares. If a processor-based implementation of the scheduler is used, the steps of the method may be performed by one or more processors of the scheduler. In such a case the scheduler may further comprise a memory in which program code for implementing the below described functionalities is stored. According to an embodiment the calculation of the relative resource shares is based on the quality of service (QoS) requirements for said wireless device and said at least another wireless device. If a QoS requirement for one wireless device comprises low latency and/or high transmission rates this wireless device may be prioritized. It may also be possible that the QoS requirements comprise a priority indication which is adapted to signal a prioritized handling of said wireless device.

According to one embodiment the relative resource share for a wireless device is calculated by multiplying the expected radio channel resources with a bit rate requirement for said wireless device. If e.g. the expected radio channel resources per bit rate has been determined as a share of 10% at a reference bit rate of 1 Mbit/s of all available radio channel resource shares and the QoS requirement comprises a bit rate of 2 Mbit/s then the share is multiplied by the quotient of

Mbit

the bit rate from the QoS requirement and the reference bit rate: 10% * = 20%. The

1

s

same calculation is done for the share for wireless device B 300. If the QoS requirements for wireless device B 300 is only 1 Mbit/s and the expected radio channel resource for wireless device B 300 is 50% due to bad radio coverage then the relative resource share remains 50%:

Mbit

50% * Hwfi _t = 50% . If the radio base station 100 only serves the two wireless devices A 200

1

s

and B 300, then both shares may be adapted to cover 100% of the available resources. For

20%

wireless device A with a share of 20% the final share is set to * 100% « 29 % and

20% + 50%

50%

for wireless device B with a share of 50% the final share is set to * 100% « 71 %.

20% + 50%

After the relative resource share for all wireless devices have been calculated the resources can be scheduled according to different algorithm. According to one embodiment in which the resource allocation is decided every 10ms all resources can be scheduled for wireless device A 200 the next 2.9ms and then for wireless device B 300 for 7.1 ms. According to another embodiment the scheduler may schedule 29 resources to wireless device A 200 and then 71 resources to wireless device B 300 every specific timeslot (e.g. 1 ms).

According to a further embodiment, the scheduling of the data transmission is done separately for uplink data transmission and downlink data transmission. The uplink data transmission is the transmission of data from the wireless device to the radio base station and the downlink data transmission is the transmission of data from the radio base station to the wireless device. Scheduling both directions separately may reduce the complexity of the scheduling algorithm and allows a better consideration of the quality of service requirements which may be different for uplink and downlink data traffic.

According to a further embodiment the scheduling of the data transmission is based on a round robin scheduling, taking into account the calculated resource shares. A round robin scheduler may base the schedule of resources on a product of a resource share parameter p and the time tsince since each wireless device has been scheduled. This calculated weight is used to decide which wireless device is scheduled at a specific time.

According to a further embodiment, which is depicted in Fig. 5, the scheduling of the data transmission on a data connection 210, 310 comprises step 510 of allocating a bucket of delay tokens to the data connection. Step 510 is a preparation step to allow the execution of the further steps. For each connection, IP flow or bearer between wireless devices 200, 300 and a radio base station 100, a bucket of delay tokens is established. Further, one delay token per transmission time interval (TTI) is allocated to said delay token bucket in step 520. The delay token may only be added if uplink or downlink data are to be transmitted via said data connection. This step 520 may be executed each transmission time interval and is a recurring process. Each delay token represents the relative resource share for said data connection per transmission time interval. In a next step 530, it is checked if a delay token is available in the delay token bucket or not. If this check is positive and a delay token is available in the delay token bucket, the data transmission is scheduled according to the relative resource share according to step 540 and the delay token is removed from the delay token bucket. Data Connections / IP flows / bearers having delay tokens in their respective buckets are considered first and the "oldest" packets are scheduled first.

According to a further embodiment step 550 may be executed if a delay token is not available in the delay token bucket in said transmission time interval. According to step 550 the data transmission is scheduled according to a round robin scheme with other wireless devices which do not have a delay token available for data transmission in said transmission time interval. Step 550 may only be applicable if there are still resources left for scheduling in this transmission time interval.

The delay token always represents the calculated relative resource shares per data connection, IP flow or bearer. If the relative resource shares changes e.g. due to a change in the connection quality, a token still represents the calculated relative resource share even if it is now higher or lower than before. The changing value of a delay token with respect to the amount of data traffic makes it possible to quickly follow the changes in given resource shares in a controlled manner while still getting the benefit of supporting variable bit rates.

Fig. 6 shows a message flow diagram for illustrating a method which may be utilized for implementing the illustrated concepts in a scheduler of a wireless communication network. According to this example the scheduler is split-up into Resource Allocator 610 and a Resource Regulator 620. The Resource Allocator 610 and the Resource Regulator 620 could be encapsulated in one scheduler or may be implemented as distributed nodes or modules in the network. According to one embodiment the Resource Allocator 610 may be allocated to a specific cell of the wireless communication network which is served by a radio base station 100 such that each cell in the network may have a Resource Allocator 610 which is responsible for scheduling the data transmissions to all wireless devices in a specific cell. The Resource Regulator 620 on the other hand may be allocated to a centralized function in the network and may be connected to more than one Resource Allocator 610.

The advantage of this distribution of functions over two separate nodes is that the Resource Allocator 610 can focus on the complex task of scheduling efficiently according to Layer 1 / Layer 2 procedures. Further it is now possible to test and verify the functionality of both parts of the scheduler separately. If an update of functionality in the scheduling behavior is needed, only the centralized Resource Regulator 620 must be updated, wherein the Resource Allocators 610 may remain unchanged. This will increase the handling and management of a complex scheduler in a wireless radio communication network.

According to the embodiment of Fig. 6, the first step 410 which corresponds to step 410 of Fig. 4, of determining expected radio channel resources per data rate for a data connection 210 between a radio base station 100 and a wireless device 200 which is served by the radio base station 100 in its cell is handled by the Resource Allocator 610 which is allocated to that specific cell. The results of the determination step are reported via a message 615 to the Resource Regulator 620. This message 615 can be send periodically to the Resource Regulator 620. This result may comprise a number of resources and the reference bit rate at which the resources are determined. It may also be possible to report shares or percentages to the Resource Regulator 620. It may be possible to use more than one message to report said result of step 410. The Resource Regulator 620 calculates in a further step 420, which corresponds to step 420 in Fig. 4, based on the expected radio channel resources per data rate, relative resource shares between said wireless device 200 and at least another wireless device 300, served by said radio base station 100. After the Resource Regulator sends the results of the calculation step 420 to the Resource Allocator 610 in a step 625, the Resource Allocator 610 schedules the data transmission on said data connection 210 based on the reported relative resource shares.

In other words, the Resource Allocator 610 performs or triggers to determine expected radio channel resources per data rate associated to the data connection 210. The Resource Allocator is further adapted to trigger or perform the step of scheduling the data transmission on said data connection 210 based on a received relative resource share which are calculated based on the expected radio channel resources per data rate. The Resource Regulator 620 performs or triggers the calculation of relative resource shares between a wireless device 200, 300 and at least another wireless device 200, 300, served by the radio base station 100, based on expected radio channel resources per data rate associated to the data connections 210, 310 between each of the served wireless devices 200, 300 and the radio base station 100. The Resource Allocator 620 is further adapted to perform or trigger the sending of the calculated relative resource shares to a Resource Allocator 610 for triggering the scheduling of data transmission on the data connections.

Fig. 7 illustrates an exemplary embodiment of a scheduler 700 which comprises a Resource Regulator 710 and a Resource Allocator 720. The Resource Regulator 710 and the Resource Allocator 720 may be located in a distributed manner in a wireless communication network as also disclosed in the embodiment of Fig. 6. The Resource Allocator 720 comprises means for scheduling the data transmission on data connections which are depicted as water taps. Each water tap is logically connected to the Resource Regulator 710 which is calculating, based on expected radio channel resources per data rate, relative resource shares between said wireless device 200 and at least another wireless device 300, served by said radio base station 100. The relative resource shares are depicted by water jets, floating off each of the water taps. A broad water jet represents a high relative resource share wherein a small water jet represents a low relative resource share. The two circled arrows may represent a round robin distribution such that each water tap is opened for a specific timeframe but with different openings such that more or less data/water is floating off each water tap.

Fig. 8 illustrates an exemplary embodiment of a scheduler 800 which is configured to operate as herein described. According to one embodiment the scheduler 800 is configured for scheduling the sending of data on a data connection 210 between a radio base station 100 and a wireless device 200. The scheduler 800 is configured to trigger or perform determining expected radio channel resources per data rate associated to said data connection 210. The scheduler is further configured to trigger or perform calculating, based on the expected radio channel resources per data rate, relative resource shares between said wireless device 200 and at least another wireless device 300, served by said radio base station 100 and to trigger or perform scheduling the data transmission on said data connection 210 based on the relative resource shares.

According to a further embodiment the scheduler 800 comprises an interface circuit 810, processing circuit 820, and memory 830. The interface circuits 810 are used to receive information from other nodes or from a wireless device 200, 300 and to send information to other nodes in the access network. The processing circuit 820 processes the information received via the interface circuits 810. In one embodiment, the processing circuit 820 comprises a determination unit 822 for determining expected radio channel resources per data rate associated to said data connection. The processing circuits 820 may further comprise a calculation unit 824 for calculating, based on the expected radio channel resources per data rate, relative resource shares between said wireless device and at least another wireless device, served by said radio base station. The processing circuits 820 may further comprises a scheduling unit 826 for scheduling the data transmission on said data connection based on the relative resource. The processing circuits 820 may comprise one or more microprocessors, hardware, firmware, or a combination thereof. In one embodiment, the determination unit 822, the calculation unit 824 and the scheduling unit 826 may be implemented by a single microprocessor. In other embodiments, the determination unit 822, the calculation unit 824 and the scheduling unit 826 may be implemented using different microprocessors.

Memory 830 comprises both volatile and non-volatile memory for storing computer program code and data needed by the processing circuit 820 for operation. Memory 830 may comprise any tangible, non-transitory computer-readable storage medium for storing data including electronic, magnetic, optical, electromagnetic, or semiconductor data storage. Memory 830 stores a computer program 832 comprising executable instructions that configure the processing circuits 820 to implement methods 400 according to FIG. 4. In general, computer program instructions and configuration information are stored in a non-volatile memory, such as a read only memory (ROM), erasable programmable read only memory (EPROM) or flash memory. Temporary data generated during operation may be stored in a volatile memory, such as a Random Access Memory (RAM). In some embodiments, the computer program 832 for configuring the processing circuit 820 as herein described may be stored in a removable memory, such as a portable compact disc, portable digital video disc, or another removable media. The computer program 832 may also be embodied in a carrier such as an electronic signal, optical signal, radio signal, or computer readable storage medium.

It is to be understood that the structure as illustrated in Fig. 8 is merely schematic and that the scheduler 800 may actually include further components which, for the sake of clarity, have not been illustrated, e.g., further interfaces or processing circuits. For example, multiple network interfaces could be provided which are configured to allow communication with different types of other nodes. Also, it is to be understood that the storage entity may include further types of program code modules, which have not been illustrated. Moreover, it is to be understood that the above concepts may be implemented by using correspondingly designed software to be executed by one or more processors of an existing device, or by using dedicated device hardware. Also, the nodes as described herein may be implemented by a single device or by multiple devices, e.g., a device cloud or system of cooperating devices.

Those skilled in the art will further appreciate that the functions explained herein below may be implemented using hardware circuitry, software means, or a combination thereof. The software means may be in conjunction with a programmed microprocessor or a general-purpose computer, using an Application Specific Integrated Circuit (ASIC) and/or Digital Signal Processors (DSPs). It will also be apparent that when the present invention is described as a method, it may also be embodied in a computer processor and a memory coupled to the processor, wherein the memory is encoded with one or more programs that perform the method when executed by the processor.