Method and apparatus for a communication network

Abstract

Method and apparatus for a communication network. One method includes: receiving (102) a plurality of cyclic data stream parameters (cp#1, cp#2) and associated QoS requirements (QoS#1, QoS#2), wherein at least one of the plurality of stream parameters (cp#1, cp#2) at least characterizes the arrival of frames of an associated cyclic data stream of a communication network (CN) and an associated communication endpoint (App#1, App#2, App#i); receiving (104) first capability information (ci1#1-3) characterizing the capabilities of corresponding wired links (l1, l2, l3) of the communication network (CN); receiving (105)... 6) Second capability information (ci2#4-5) characterizing the capabilities of the corresponding radio links (l3, l5) of the communication network (CN); determining (108) pre-scheduling (PS) based on multiple cyclic data stream parameters (cp#1, cp#2), associated QoS requirements (QoS#1, QoS#2), first network capability information (ci1#1-3) and second capability information (ci2#4-5); and configuring (110) at least one network entity (SCHED#1, NE#1-6) of the communication network (CN) based on the determined at least one pre-scheduling (PS).

Description

Background Technology

[0001] In the context of Industry 4.0, wireless communication is finding its way into the factory floor on a massive scale. This brings highly flexible networks and vertical integration to factories, making future manufacturing extremely customizable and highly efficient. However, this flexibility comes at the cost of increased complexity in managing such networks, especially given the stringent QoS requirements that must be met in many real-time industrial applications. In wired communication systems such as Time-Sensitive Networking (TSN), end-to-end service guarantees (such as bounded latency) are achieved by scheduling each user and applying traffic shaping mechanisms (e.g., time-aware shaping). Summary of the Invention

[0002] The problems of the prior art are solved by the method according to claim 1 and the apparatus according to the other claims.

[0003] According to the first aspect described, a method includes: receiving a plurality of cyclic data stream parameters and associated QoS requirements, wherein at least one of the plurality of stream parameters at least characterizes the arrival of frames of associated cyclic data streams and associated communication endpoints of a communication network; receiving first capability information characterizing the capabilities of corresponding wired links of the communication network; receiving second capability information characterizing the capabilities of corresponding wireless links of the communication network; determining a pre-scheduling based on the plurality of cyclic data stream parameters, the associated QoS requirements, the first network capability information, and the second capability information; and configuring at least one network entity of the communication network based on the determined at least one pre-scheduling.

[0004] Advantageously, suitable pre-scheduling is determined on heterogeneous networks consisting of wired TSNs and wireless networks. Different constraints are given by the respective systems, and this method allows for end-to-end optimization of each data stream.

[0005] A favorable example is characterized in that the determination of pre-scheduling includes: successively selecting at least one segment of the communication network based on first network capability information and second capability information; and determining at least one preliminary instance of pre-scheduling of the selected segment of the communication network based on multiple cyclic data stream parameters and associated QoS requirements associated with the first segment.

[0006] Advantageously, network segments allow for faster computation of pre-scheduling compared to immediately computing the pre-scheduling of the entire network.

[0007] An advantageous example is characterized in that the first selected segment includes a wireless or wired link, and wherein the second segment includes a wired or wireless link.

[0008] Advantageously, this separation can be determined by the corresponding link attributes.

[0009] A favorable example is characterized in that the selection of the first selected segment includes: determining multiple current uses associated with wired and wireless links based on the provided first and second capability information; determining the first selected segment includes: links with multiple connections associated with current use that are above a usage threshold.

[0010] If a segment in the network is under high load of real-time cross traffic, the segment should first be pre-scheduled for low latency, as it will become a bottleneck in the communication network for the end-to-end cyclic data flow under consideration.

[0011] An advantageous example is characterized in that the selection of the first selected segment includes: determining multiple bandwidths of wired and wireless links based on the provided first and second capability information; and determining the first selected segment, which includes links of multiple connections in the link having associated bandwidths below a bandwidth threshold.

[0012] If one segment of a network has significantly lower available bandwidth compared to the rest of the communication network, it is beneficial to optimize resource efficiency to prevent other users from going hungry.

[0013] A favorable example is characterized in that the pre-scheduling includes at least one gating list associated with at least one network entity serving at least one of the wired links in the communication network.

[0014] Advantageously, at least one gating list is determined based on second capability information that characterizes the capabilities of the corresponding wireless links in the communication network.

[0015] A favorable example is characterized in that the pre-scheduling includes at least one network entity configured to schedule at least one network entity serving at least one of the radio links of the communication network for each time unit and each radio link.

[0016] Advantageously, the expected cycle traffic volume for each time unit and each wireless link is determined based on the first capability information characterizing the capabilities of the corresponding wired link.

[0017] An advantageous example is characterized in that the pre-scheduling includes at least one gating list for at least one wired link of a network converter entity, and expected cyclic traffic for each time unit and each radio link of a scheduler entity configured to schedule network converter entities serving at least one of the radio links associated with the network converter entity.

[0018] Advantageously, via a pre-scheduled centralized pre-scheduled network converter entity.

[0019] According to a second aspect of this specification, an apparatus is provided, comprising: a receiving unit for receiving a plurality of cyclic data stream parameters and associated QoS requirements, wherein at least one of the plurality of stream parameters characterizes at least the arrival of frames of associated cyclic data streams and associated communication endpoints of a communication network; a receiving unit for receiving first capability information characterizing the capability of a corresponding wired link of the communication network; a receiving unit for receiving second capability information characterizing the capability of a corresponding wireless link of the communication network; a determining unit for determining a pre-scheduling based on the plurality of cyclic data stream parameters, the associated QoS requirements, the first network capability information, and the second capability information; and a configuring unit for configuring at least one network entity of the communication network based on the determined at least one pre-scheduling.

[0020] An advantageous example is characterized in that the determining component for determining pre-scheduling includes: a selection component for sequentially selecting at least one segment of a communication network based on first network capability information and second capability information; and a determining component for determining at least one preliminary instance of pre-scheduling for the selected segment of the communication network based on a plurality of cyclic data stream parameters and associated QoS requirements associated with the first segment.

[0021] An advantageous example is characterized in that the first selected segment includes a wireless or wired link, and wherein the second segment includes a wired or wireless link.

[0022] A favorable example is characterized in that the selection of the first selected segment includes: determining multiple current uses associated with wired and wireless links based on the provided first and second capability information; determining the first selected segment includes links with multiple connections in the links that have associated current uses above a usage threshold.

[0023] An advantageous example is characterized in that the selection component for selecting a first selected segment includes: a determining component for determining multiple bandwidths of wired and wireless links based on provided first and second capability information; and a determining component for determining a first selected segment of a link that includes multiple connections in the link having associated bandwidths below a bandwidth threshold.

[0024] A favorable example is characterized in that the pre-scheduling includes at least one gating list associated with at least one network entity serving at least one of the wired links in the communication network.

[0025] A favorable example is characterized in that the pre-scheduling includes at least one network entity configured to schedule at least one network entity serving at least one of the radio links of the communication network for each time unit and each radio link.

[0026] An advantageous example is characterized in that the pre-scheduling includes a gating list for at least one wired link of a network converter entity, and the expected cyclic traffic for each time unit and each radio link of a scheduler entity configured to schedule network converter entities serving at least one of the radio links associated with the network converter entity.

[0027] Another aspect of this specification relates to the use of the method according to the first aspect or the apparatus according to the second aspect. Attached Figure Description

[0028] Figure 1 A communication network and a device for determining the pre-scheduling of the communication network are schematically depicted. Figure 2 , Figure 3 and Figure 4 The flowcharts are depicted schematically; and Figure 5 The grouping of the corresponding cyclic data stream is schematically depicted.

[0029] Figure 1 A communication network CN and a pre-scheduled PS for determining the communication network CN are schematically depicted. The exemplary communication network CN consists of a TSN and a 5G-based TSN network entity.

[0030] Apparatus 100 includes a receiving component for receiving 102 plurality of cyclic data stream parameters cp#1, cp#2 and associated QoS requirements QoS#1, QoS#2. At least one of the plurality of stream parameters cp#1, cp#2 characterizes at least the arrival of frames in the associated cyclic data stream, the associated frame size, and the associated communication endpoints App#1, App#2, App#i of the communication network CN. Endpoints App#1, App#2, App#i represent real-time applications, such as industrial control applications, executed on or directly linked to one of the network entities NE#1-6 in the communication network CN.

[0031] The device 100 includes a receiving component or receiving interface for receiving 104 first capability information ci1#1-3, which characterizes the capabilities of corresponding wired links l1, l2, l3 of the communication network CN.

[0032] The apparatus 100 includes: a receiving component for receiving second capability information ci2#4-5 characterizing the capabilities of corresponding radio links l3, l5 of the communication network CN.

[0033] As shown in the example, capability information ci2 is information about the current channel conditions for each user or network entity NE#4-6. This information can be taken into account in end-to-end scheduling. For example, even under impaired channel conditions, better resilience can be achieved for users' higher and inconsistent resource demands by scheduling longer time slots.

[0034] The first and second capability information c1#1-3 and c2#4-5 include static or dynamic parameters describing the corresponding attributes of the links or network entities of the communication network CN.

[0035] The apparatus 100 includes: a determining component for determining 108 pre-scheduled PSs based on multiple cyclic data stream parameters cp#1, cp#2, associated QoS requirements QoS#1, QoS#2, first network capability information ci1#1-3 and second capability information ci2#4-5.

[0036] Apparatus 100 includes a configuration component for configuring at least one network entity SCHED#1, NE#1-6 of communication network CN 110 based on at least one pre-scheduled PS. According to an example, configuring 110 includes the transmission of at least a portion of the pre-scheduled PS.

[0037] The pre-scheduled PS includes at least one gating list associated with network entities NE#1-4 serving at least one of the wired links l1, l2, and l3 of the communication network CN. Data transmission prioritization is performed at the egress port of the corresponding network entity NE#1-4 serving the respective wired link l1-l3. Transmission is determined based on the Transmission Selection Algorithm (TSA). If data from a specific queue is selected, the corresponding gate is opened to transmit the data. The gate opening event is determined by the gating list. Therefore, coordination between different data flows is guaranteed, and a protection window is provided to ensure that high-priority data has guaranteed access to the network at a specific time. Specific traffic categories are allowed to be transmitted within a specific time period.

[0038] According to the example, the pre-scheduled PS includes at least the expected cyclic traffic for each time unit and each radio link l4, l5 for scheduler entity SCHED#1, which is configured to schedule at least one network entity NE#4-6 serving at least one of radio links l4, l5 of communication network CN. Therefore, scheduler entity SCHED#1 can exclusively reserve a certain amount of radio resources in advance for online scheduling of packets associated with the pre-scheduled cyclic data stream.

[0039] According to the example, the pre-scheduled PS includes a gating list for at least one wired link l3 of a network entity NE#4, specifically referred to as a network converter, and the expected cyclic traffic for each time unit and each radio link l4, l5 of the scheduler entity SCHED#1. The scheduler entity SCHED#1 is configured to schedule network converter entity NE#4 to serve at least one of the radio links l4, l5 associated with network converter entity NE#4. Network entity NE#4 uses at least one gating list to serve wired link l3.

[0040] Based on the concept of a logical bridge, network segment seg#2 represents a single TSN node. Accordingly, each individual 5G node NE#4-6 also has a converter to act as a TSN node to the outside world. Therefore, network entities NE#5 and NE#6 also have converters for applications app#1, 2, and 3 (although in this case, they have no scheduling function because the links are not scheduled to the apps).

[0041] To find the optimal scheduling for end-to-end cyclic data streams on heterogeneous networks, all streams across network entities must be jointly optimized. The network is a time-triggered system where the transmission time of each frame can be precisely triggered—both in endpoint applications and at each network entity—based on a common time shared across all network entities.

[0042] Scheduling is roughly divided into two categories: The first category performs scheduling at the per-frame level. For each frame arriving at a network entity, the scheduler determines when to schedule that frame. We call this type of scheduling "online scheduling." The second category provides pre-scheduled resources (PSs) that include resources prior to the arrival of the corresponding frame at the network entity, based on knowledge about frame arrival, for example, in industrial applications where communication is performed in a deterministic cycle. Pre-scheduling is determined in advance; we call this "offline scheduling." This description addresses the latter case of pre-configured scheduling, i.e., pre-scheduled PSs.

[0043] The provided framework offers users or applications a set of transmission time offsets as part of a pre-scheduled PS that determines which network node must reserve resources for which frame. This configuration can then be translated into or include a corresponding gating list of TSN network entities, or a corresponding resource allocation in a 5G system. For 5G systems, due to channel uncertainty, this pre-configured scheduling is not determined at a low level (i.e., the reservation of individual resource elements at the physical layer). Therefore, a two-stage approach is used. First, a pre-scheduled PS is determined to reserve the corresponding time slots based on a suitable estimate of the channel. Second, the online scheduler SCHED#1 determines the precise resource allocation at the physical layer at the per-frame level.

[0044] This concept is also used in the framework of TSN bridges and 5G virtual bridge systems, such as in Figure 1 As shown in the diagram. For TSN systems, the end-to-end scheduler can directly schedule each frame, making it possible to determine the gating list. In the 5G case, firstly, the pre-scheduled PS includes: an approximate scheduling based on available transmission resources. This pre-scheduled PS is then used as scheduler SCHED#1 in the online 5G MAC scheduler to allocate specific resources on the radio link. To operate such end-to-end scheduling, capability information from the bridge and the configuration of available interfaces are provided. For TSN bridges or network converter entities, the gating list is determined externally. The network converter entity applies the gating list to the egress ports of its bridge via a remote configuration protocol.

[0045] Advantageously, the latency and bit rate for each user, as well as the cyclic data stream, remain constant over time, allowing for pre-scheduling calculations. A possible implementation example exposes the 5GS bridge's capability information in the sense of a network converter entity. This information could include buffer status, link quality, serving users, experienced latency, etc., and could be made available at the TSN AF (TSN Application Function) through an existing connection to the external TSN network control plane. In another example, UE-specific parameters (such as latency within the UE (between DS-TT and UE AN), latency from the UE to the NW-TT, propagation delay or other delays, channel / link quality, packet delay budget, QoS flow, etc.) could be reported by the UE and sent to the TSN-AF or measured between DS-TT and NW-TT. These values ​​are reported to the TSN-AF, where they are communicated to the TSN network. The scheduler could then, for example, be placed outside the TSN AF.

[0046] According to the example, TSCAI (TSC Auxiliary Information) is transmitted from the core network (CN) to the gNB in ​​the sense of scheduler SCHED#1. The order of the preceding transmissions is as follows: from TSN-AF to Session Management Function (SMF), and then to the gNB in ​​the sense of scheduler SCHED#1. TSN-AF is responsible for obtaining PSFP (IEEE 802.1Q) and creating containers for each flow or multiple flows. SMF appends QoS flows and bursts periodically, and sends the containers to the gNB.

[0047] The SMF maps bursts / periodic arrivals from the TSN clock to the 5G clock. Then, if a mismatch exists, the User Plain Function (UPF) updates the SMF by updating the Cumulative Rate Ratio. Based on the latter value, the SMF corrects the TSCAI and sends it back to the gNB.

[0048] According to the example, the capability information includes at least one of the following latency measurements: 5GSIndependentDelayMin, independentDelayMax, and txPropagationDelay.

[0049] Additionally, reporting to 5GS in the sense of scheduler entity SCHED#1 includes: - After the PDU session is established, the bridging information of the 5GS bridge in the sense of network translation entity will be reported to the TSN network; - Map TSN flow requirements obtained from the TSN network to 5GS QoS information (e.g., 5QI, TSC auxiliary information) of the QoS flow in the corresponding PDU session for efficient time-aware scheduling; - Functionality of 5GS bridges as defined in 802.1Qcc, such as 5GS bridge latency for each port pair for each traffic class, including 5GS bridge latency (dependent and independent of frame size, and their maximum and minimum values: independentDelayMax, independentDelayMin, dependentDelayMax, dependentDelayMin), ingress port number, egress port number, and traffic class; and / or propagation delay (txPropagationDelay) for each port, including transmission propagation delay and egress port number.

[0050] The TSN AF is responsible for receiving bridge information from the 5GS bridge and registering or updating that information to the TSN network.

[0051] According to the example, device 100 is arranged outside the TSN-AF and connected to an interface from the outside to the TSN-AF. The TSN-AF is internally connected to the NW-TT (Network-Side TSN Converter).

[0052] According to the example, device 100 is divided into two parts. One part is inside the TSN-AF and connected to an external TSN network segment. The second part of device 100 is located outside the TSN-AF and connected to the internal part. A connection is arranged between the CNC (Centralized Network Configuration) and the TSN AF.

[0053] Consider the communication network (CN) in a joint manner. With the increasing size of the network, this can become a computationally intensive task. Therefore, problem relaxation or heuristic methods can be applied to find a solution within a feasible computational time. Additionally, the optimization objective can be applied to different network segments to reduce the problem set and take into account network-specific characteristics, as illustrated below.

[0054] Figure 2 Depicting Figure 1 A schematic flowchart of step 108 is provided. A determining component is provided to read the first and second capability information at 202. For example, the first and second capability information includes at least one of the following: node capabilities and link capabilities. The node capability includes the current state of the corresponding node, and the link capability includes the current state of the corresponding link.

[0055] The determining component for pre-scheduling includes a selection component that successively selects at least one segment of the 204 communication network based on first network capability information and second capability information. Therefore, selecting 204 represents the selection of a sub-network segment. The idea is to break down the network into iteratively optimized sub-network segments. This allows for significantly faster computation of feasible solutions that may not be globally optimal. At least one selected network segment exhibits characteristics that distinguish it from the rest of the network. This could be due to different underlying networking technologies within the segment, or due to the influence of current traffic.

[0056] For example, the first selected segment seg#2 includes a wireless link, and the second segment seg#1 includes a wired link.

[0057] In another example, the first selected segment seg#3 was chosen because links l3 and l4 have above-average current usage.

[0058] In yet another example, the first selected segment seg#3 was chosen to provide a lower-than-average bandwidth for links l3 and l4.

[0059] A selection component is provided to choose at least one of 206 optimization objectives. Depending on the configuration of the communication network, multiple optimization objectives can be formulated to solve the constrained problem. Examples of at least one optimization objective include: - Minimize the worst-case end-to-end wait time stream(i).delay; - Minimize the per-link wait time for each packet stream: stream(i).packet(j).delay([link(l)]); - Minimize the worst-case end-to-end jitter stream(i).∆delay; - Maximize the utilization of 5G links, that is, maximize the sum of the rates link(l).maxRate(t, b) on all 5G links in all resource blocks B; and - Maximize the number of users supported.

[0060] An adjustment component is provided to adjust the constraints of the segment for selecting the communication network in 208.

[0061] The determining component 210 is provided to determine whether the selected constraints can be satisfied by the selected segment of the communication network.

[0062] If the selected segment cannot satisfy the selected constraints, the component is determined to determine a solution to the 218 conflict, for example by adjusting at least one constraint and / or at least one optimization objective.

[0063] If the selected segment satisfies the selection constraints, the determining component determines at least one preliminary instance of pre-scheduling of the selected segment among the segments of the communication network based on multiple cyclic data flow parameters, associated QoS requirements, and network capability information associated with the first segment. Specifically, determining 212 includes: determining a solution to optimize the selected objective, for example, the offset associated with the link of the network entity.

[0064] For example, constraints define a set of feasible possible scheduling implementations. These constraints are defined for heterogeneous communication networks consisting of TSNs and TSN-over-5G subnetworks. For instance, pre-scheduling can be determined via three types of input parameters: the network model and configuration of the given communication network in the form of corresponding capability information; the parameters and configuration of the i-th flow in the communication network in the form of cyclic data flow parameters—where I = 1, 2, ..., S and S is the total number of cyclic data flows; and the user requirements for each cyclic data flow in the form of associated QoS parameters.

[0065] The task of this device is to determine the pre-scheduling of planned packets for each hop in the communication network. For example, for each flow i = 1..S, each packet j = 1..Pi in that flow, and each link l = 1..Li through which the packet traverses, the pre-scheduling can be determined by the transmission offset. ,j,l are uniquely defined, such as in Figure 5 As shown in the image.

[0066] For a link(l) in a link, l = 1..L, at least one capability information includes at least one of the following: - Link type (5G, TSN, etc.): link(l).type; - Available bandwidth on each link: link(l).maxRate; and - Transmission delay for each link: link(l).delay.

[0067] For a stream(i) in a cyclic data stream, at least one cyclic data stream parameter includes at least one of the following: - Network configuration: Number of links: link(l); - Frame arrival time (e.g., as cycle time): stream(i).cycleTime; and - Payload per frame: stream(i).packetSize.

[0068] For a stream(i) in a cyclic data stream, at least one QoS parameter associated with at least one cyclic data stream parameter includes at least one of the following: - Target end-to-end delay on the network: stream(i).delay; - Target end-to-end jitter: stream(i).∆delay; and - Target grouping error rate: stream(i).errorRate.

[0069] Provide an update component to at least update the offset determined in step 212 of step 216.

[0070] Constraints are determined based on capability information. In yet another example, capability information represents constraints. These constraints can be grouped into general network constraints and technology-specific constraints, such as TSN and 5G in this case.

[0071] Network constraints include at least one of the following: - Frame constraint: For each stream i = 1..S, its frames j = 1..P must have a transmission offset stream(i).frame(j), which is positive and scheduled within its cycle time stream(i).cycleTime; - Transmission order: Each frame in a communication network is transmitted at the next link (l) after it has been fully received in advance at the previous link (l-1). stream(i).packet(j).offset[link(l − 1)] <stream(i).packet(j).offset[link(l)]; - End-to-end latency: Each frame in a communication network has a latency budget within that frame and must be delivered to the appropriate endpoint: stream(i).packet(j).offset[link(Li)]− stream(i).packet(j).offset[link(1)] <stream(i).delay。

[0072] Additionally, more demand-based constraints can be defined for each stream, such as for jitter stream(i).∆delay or packet loss stream(i).errorRate. Constraints on delivery order can also be applied, for example, if frames must be transmitted in bursts.

[0073] TSN constraints include at least one of the following: - Single-link usage: Each wired TSN link (link(l).type = TSN) is exclusively used by a single frame at a time. Therefore, we must ensure that any two packets stream(i).packet(j) in the network do not interfere with the same link; that is, we must ensure that exclusive access is scheduled for each frame. - Well-defined windows. In a wired TSN segment, each frame is not scheduled individually, but rather based on its traffic class. A TSN supports a maximum of eight traffic classes, which group frames of different flows with the same or similar requirements. If a pre-scheduled packet belongs to a single traffic class, this constraint ensures that the corresponding traffic class gate in the gated list (GCL) is open at the appropriate egress port; - Handle constraints of multiple traffic categories for concurrent access links; - Inlet filtering; and - Queuing behavior.

[0074] Radio domain constraints include at least one of the following: - Transmission Opportunities: Unlike Ethernet-based systems where frames can be transmitted at any time, frames in the radio domain can only be sent at specific discrete points in time. These transmission opportunities are configurable, but are typically fixed per stream during operation and depend on the Transmission Time Interval (TTI): For link(l).type = 5G. - Transmission Resources: Unlike Ethernet systems, frames in wireless systems are scheduled not only over time but also, depending on the technology, frequency, code, and antenna. In the case of 5G, we consider both time and frequency, allowing frames to be transmitted simultaneously on different frequencies. Instead of the constant rate `link(l).maxRate` dependent on the link in an Ethernet link, we consider a dynamic transmission rate over time `t` and frequency `b`, which is also different for each user `i` (i.e., the stream) in the communication network due to channel variations. Therefore, we use a different notation that quantifies the transmission rate of each time-frequency resource block with a corresponding dependency: `link(l).maxRate(t, b, i)`. The total rate per TTI of the wireless link is constrained by the total number of supported resource blocks `B`. Since the behavior of `maxRate(t, b, i)` is highly dynamic, we rely on assumptions and estimates about the channel. This is why the application includes a two-stage scheduling method that includes pre-scheduling determination and online scheduling based on pre-scheduling determination.

[0075] The determination of pre-schedules based on constraints in the form of capability information is illustrated below. Several options exist regarding how to derive pre-schedules from capability information. Possible solver frameworks include, for example, (M)Integer Linear Programming ((M)ILP), Constrained Programming (CP), or Satisfiability Modular Theory (SMT). Different approaches can be conceived regarding optimality: - No optimization: Based on constraints, one can derive a schedule that satisfies all necessary requirements. Often, there are many solutions or no solutions at all. Therefore, constraints are only used to determine whether the satisfiability of the scheduling problem is feasible. - Single-run optimization: It is possible to specify a single optimization objective, that is, a value that should be minimized or maximized while satisfying constraints. For example, minimizing the sum of all worst-case end-to-end wait times for all flows is such an optimization objective. - Multiple optimization. Optimizing multiple parameters at once is generally not directly applicable to constraint-based problems. However, it is possible to formulate a cost function based on multiple parameters, which can then be minimized or maximized. For example, minimizing end-to-end latency and jitter are two optimization objectives, which can be considered together by considering the cost function F(.): .

[0076] A determining component is provided to determine whether all segments have been accessed in order to determine the corresponding preliminary schedule. If yes, the preliminary pre-schedule is determined as the final pre-schedule. If another segment of the communication network is waiting for the determination of the corresponding preliminary pre-schedule, the procedure continues to step 204.

[0077] This method performs well for correctly selected network segments. In cases such as... Figure 1 In the case of TSN and TSN-over-5G implementations illustrated in the examples, information for determining appropriate segments can be easily extracted because all network participants provide information to [the relevant network]. Figure 1 The device 100 provides information about network status and node capabilities. Using these input parameters, the centralized device determines appropriate segments of the network and deploys configurations to the network in a pre-scheduled manner.

[0078] A possible approach would be to first investigate the available and required bandwidth for all cyclic data flows on each network entity. The more users that must share the same link, the greater the impact of pre-scheduling on overall end-to-end performance. Therefore, we first select the coherent set of nodes with the highest utilization in the network. Then, we determine the optimization objective for that segment and adjust the constraints. For example, we set a new latency constraint for one of the segments, which must, of course, be lower than the end-to-end latency requirement stream(i).delay. We can now optimize this sub-network and determine the transmission offset of the cyclic data flows through that link. Subsequently, we iteratively continue to solve for the offsets on all remaining links in the communication network.

[0079] After the subnetworks have been pre-determined, there is a chance that scheduling will be infeasible, i.e., there will be scheduling conflicts that do not satisfy the constraints. In this case, there are two options: either determine different segments or readjust the constraints of the subnetworks. This does not happen frequently; otherwise, it indicates that the instructions for selecting segments were not correct, or in general, it is not well applied to the communication network under consideration. The more heterogeneous the network, the better the method will perform.

[0080] Figure 3 A schematic flowchart is depicted. The selection component of the segment for selecting the first selection includes: determining 302 multiple current uses associated with wired and wireless links based on the provided first and second capability information; and determining 304 the segment for selecting the first selection includes: links with multiple connections associated with current use that are above a usage threshold.

[0081] Figure 4 A schematic flowchart is depicted. The selection of the first selected segment 204 includes: determining multiple bandwidths of wired and wireless links 402 based on the provided first and second capability information; and determining that the first selected segment 404 includes: links with multiple connections having associated bandwidths below a bandwidth threshold. After a resource-efficient solution has been obtained—while still maintaining some upper bound on the waiting time for the selected segment—the remainder of the network can be optimized to achieve the lowest end-to-end waiting time for a given pre-scheduled segment.

[0082] Figure 5The diagram schematically depicts the packetization of the corresponding cyclic data stream by offset scheduling at each link in the communication network. For example, summarizing the offset along the selected path through the communication network allows for checking whether the associated QoS parameters in terms of latency can be met.

Claims

1. A method for a communication network, comprising: Receive (102) a plurality of cyclic data stream parameters (cp#1, cp#2) and associated QoS requirements (QoS#1, QoS#2), wherein at least one of the plurality of stream parameters (cp#1, cp#2) at least characterizes the arrival of frames of the associated cyclic data stream of the communication network (CN) and the associated communication endpoints (App#1, App#2, App#i); Receive (104) first capability information (ci1#1-3) characterizing the capabilities of the corresponding wired links (l1, l2, l3) of the communication network (CN). Receive (106) second capability information (ci2#4-5) characterizing the capabilities of the corresponding radio links (l3, l5) of the communication network (CN). The (108) pre-scheduling (PS) is determined based on multiple cyclic data stream parameters (cp#1, cp#2), associated QoS requirements (QoS#1, QoS#2), first network capability information (ci1#1-3), and second capability information (ci2#4-5), wherein determining the (108) pre-scheduling (PS) includes: Based on the first network capability information (ci1#1-3) and the second capability information (ci2#4-5), at least one segment (seg#1-3) of the communication network (CN) is selected consecutively (204). Based on multiple cyclic data stream parameters (cp#1-2), associated QoS requirements (QoS#1-2) related to the first segment (seg#1-3), and network capability information (ci), determine (212) at least one preliminary instance of pre-scheduling (PS) for selected segments in the segments (seg#1-3) of the communication network (CN); and Configure at least one network entity (SCHED#1, NE#1-6) of the (110) communication network (CN) based on at least one pre-scheduling (PS).

2. The method according to claim 1, wherein, The first selected segment (seg#2; seg#1) includes a wireless or wired link (l4-l5; l1-3), and the second segment (seg#1; seg#2) includes a wired or wireless link (l1-3; l4-5).

3. The method according to claim 1, wherein, The selection (204) of the first selected segment (seg#1-3) includes: Based on the provided first and second capability information (cp1, cp2), determine (302) multiple current uses associated with wired and wireless links (l1-5); The first selected segment (seg#1-3) is determined to include: links (l1-5) with multiple currently used associated connections that are above the usage threshold.

4. The method according to claim 1, wherein, The selection (204) of the first selected segment (seg#1-3) includes: Based on the provided first and second capability information (cp1, cp2), determine multiple bandwidths of the wired and wireless links (l1-l5) (402); Determine (404) the first selected segment (seg#1-3), which includes multiple links in the links (l1-5) with associated bandwidth below the bandwidth threshold.

5. The method according to any one of claims 1-4, wherein, Pre-scheduling (PS) includes at least one gating list associated with at least one network entity (NE#1-4) serving at least one of the wired links (l1, l2, l3) of the communication network (CN).

6. The method according to any one of claims 1-4, wherein, Pre-scheduling (PS) includes at least: the expected cyclic traffic for each time unit and each radio link (l4, l5) for the scheduler entity (SCHED#1), the scheduler entity (SCHED#1) being configured to schedule at least one network entity (NE#4-6) serving at least one of the radio links (l4, l5) of the communication network (CN).

7. The method according to claim 5, wherein, Pre-scheduling (PS) includes: at least one gating list for at least one wired link (l3) of the network converter entity (NE#4), and expected cyclic traffic for each time unit and each radio link (l4, l5) of the scheduler entity (SCHED#1), which is configured to schedule network converter entities (NE#4) serving at least one of the radio links (l4, l5) associated with the network converter entity (NE#4).

8. An apparatus (100) for a communication network, comprising: A receiving component is configured to receive (102) a plurality of cyclic data stream parameters (cp#1, cp#2) and associated QoS requirements (QoS#1, QoS#2), wherein at least one of the plurality of stream parameters (cp#1, cp#2) at least characterizes the arrival of frames of the associated cyclic data stream of the communication network (CN) and the associated communication endpoints (App#1, App#2, App#i); The receiving unit is used to receive (104) first capability information (ci1#1-3) characterizing the capability of the corresponding wired links (l1, l2, l3) of the communication network (CN). The receiving unit is used to receive (106) second capability information (ci2#4-5) characterizing the capability of the corresponding radio links (l3, l5) of the communication network (CN). A determining component is used to determine (108) pre-scheduling (PS) based on multiple cyclic data stream parameters (cp#1, cp#2), associated QoS requirements (QoS#1, QoS#2), first network capability information (ci1#1-3), and second capability information (ci2#4-5), wherein the determining component for determining (108) pre-scheduling (PS) includes: The selection component is used to select at least one segment (seg#1-3) of the communication network (CN) in succession based on the first network capability information (ci1#1-3) and the second capability information (ci2#4-5). The determining component is used to determine (212) at least one preliminary instance of pre-scheduling (PS) for selected segments in the segments (seg#1-3) of the communication network (CN) based on multiple cyclic data stream parameters (cp#1-2), associated QoS requirements (QoS#1-2) associated with the first segment (seg#1-3), and network capability information (ci); and Configuration component for configuring at least one network entity (SCHED#1, NE#1-6) of the (110) communication network (CN) based on at least one determined pre-scheduling (PS).

9. The apparatus (100) according to claim 8, wherein, The first selected segment (seg#2; seg#1) includes a wireless or wired link (l4-l5; l1-3), and the second segment (seg#1; seg#2) includes a wired or wireless link (l1-3; l4-5).

10. The apparatus (100) according to claim 8, wherein, The selection components for selecting the first selection segment (seg#1-3) of (204) include: The determining component is used to determine (302) multiple current uses associated with wired and wireless links (l1-5) based on the provided first and second capability information (cp1, cp2); A determining component for determining (304) a first selected segment (seg#1-3) of a link (l1-5) that has multiple associated currently used connections above a usage threshold.

11. The apparatus (100) according to claim 8, wherein, The selection (204) of the first selected segment (seg#1-3) includes: A determining component is used to determine multiple bandwidths of the wired and wireless links (l1-l5) based on the provided first and second capability information (cp1, cp2); A determining component for determining (404) a first selected segment (seg#1-3) of a link (l1-5) comprising multiple connections having associated bandwidths below a bandwidth threshold.

12. The apparatus (100) according to any one of claims 8 to 11, wherein, Pre-scheduling (PS) includes at least one gating list associated with network entities (NE#1-4) serving at least one wired link (l1, l2, l3) of the communication network (CN).

13. The apparatus (100) according to any one of claims 8 to 11, wherein, Pre-scheduling (PS) includes at least: the expected cyclic traffic for each time unit and each radio link (l4, l5) for the scheduler entity (SCHED#1), the scheduler entity (SCHED#1) being configured to schedule at least one network entity (NE#4-6) serving at least one of the radio links (l4, l5) of the communication network (CN).

14. The apparatus (100) according to claim 12, wherein, Pre-scheduling (PS) includes: a gating list for at least one wired link (l3) of the network converter entity (NE#4), and the expected cyclic traffic for each time unit and each radio link (l4, l5) of the scheduler entity (SCHED#1), which is configured to schedule network converter entities (NE#4) to serve at least one of the radio links (l4, l5) associated with the network converter entity (NE#4).

15. Use of the apparatus (100) according to any one of claims 8 to 14 in a communication network.

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