KR20230161335A - Method and apparatus for on-time packet forwarding based on resource - Google Patents

Abstract

This disclosure relates generally to communication systems, and more specifically to a time-sensitive packet delivery method that guarantees the maximum/minimum delay requirements of a service, receiving link and node delay information and node buffer resource information on the path. A process of calculating the local delay budget that other nodes must guarantee based on the buffer resource information of the last node, a process of controlling nodes to transmit packets based on the local delay budget, and Within the local delay budget After nodes transmit packets, the last node can ultimately guarantee the remaining delay budget.

Description

Resource-based on-time packet forwarding method and device {METHOD AND APPARATUS FOR ON-TIME PACKET FORWARDING BASED ON RESOURCE}

This disclosure relates to a time-determined packet delivery method in packet networks such as Ethernet, IP, MPLS, etc., to ensure the delay time required for traffic to be delivered through the network, based on clear resource information. This relates to a packet delivery method and device that guarantees delay time.

Recently, in the network technology field, research and development is underway on industrial convergence network technology that can simultaneously accommodate time-sensitive (citizen) traffic such as general management traffic and real-time remote control traffic in a single network. In the application of Industry 4.0, control and telemetry data must be delivered at the target critical time for industrial automation and distributed manufacturing through remote control of robots, machines, etc.

In particular, actuators such as sensors, robots, and machines in the industrial area and the process logic controller (PLC) that controls them perform closed-loop control by exchanging measurement data and control data at regular time intervals. The process is precisely controlled in the form of . In these applications, even if data arrives early, it must wait for a set processing time, and for this, each end device must have a buffer. If data arrives late beyond the set processing time, the process does not operate as planned, so the period of the closed control loop must be increased to match the maximum expected delay time. This ultimately causes a problem that reduces control precision. Additionally, as the difference between the maximum delay and minimum delay increases, a problem arises in which the buffer size at each end device must be increased.

In order to meet the requirements of the above applications, it is no longer sufficient to simply optimize the network and minimize delay according to the existing method, and jitter represents the delay time required for traffic to be delivered to the end and the delay deviation between packets. In order to guarantee a quantified target time, the maximum/minimum delay time must be guaranteed.

Based on the above-described discussion, this disclosure is a resource-based on-time that ensures that the total delay time experienced by service traffic while being transmitted through the network satisfies the quantified maximum/minimum delay target time required by the service. Provides a device and method for packet delivery.

According to various embodiments of the present disclosure, a time-specific packet delivery method that guarantees the maximum/minimum delay requirements of a service includes a process of receiving link and node delay information and node buffer resource information on the path, and buffer resource information of the last node. A process of calculating the local delay budget that other nodes must guarantee based on, a process of controlling nodes to transmit packets based on the local delay budget, and a remaining delay budget after nodes transmit packets within the local delay budget. It may include a method of controlling the last node to finally guarantee.

According to one embodiment, the buffer resource information of the last node may be determined based on the buffer size allocated to the service and the properties of the service.

According to one embodiment, the process of controlling nodes to transmit packets based on the local delay budget may include setting clear upper and lower limits of the local delay budget that each node must guarantee.

According to one embodiment, the process of controlling nodes to transmit packets based on the local delay budget includes collecting buffer resource information of all nodes and determining the delay time that can be provided based on the buffer resources of each node. It may include the process of calculating the local delay budget of each node that does not exceed.

According to one embodiment, the local delay budget may be determined based on the total network delay and the remaining delay time minus the delay that the last node can guarantee to ensure service delay requirements.

According to one embodiment, in order for the last node to finally guarantee the remaining delay budget, a process of transmitting delay information actually consumed by each node to the last node when nodes transmit packets within the upper and lower limits of the local delay budget; , It may include a process of identifying the remaining delay budget based on actual delay information received from previous nodes, and setting the identified remaining delay budget as the local delay budget of the last node.

According to one embodiment, when the upper limit of the remaining delay is greater than the maximum delay that can be provided based on the buffer resources of the last node, a method of determining the local delay budget upper limit of the last node as the maximum delay that the last node can provide .

According to one embodiment, the properties of the service may include information about the packet delivery period, the number of packets delivered within the period, and the packet size.

According to various embodiments of the present disclosure, in a device for time-specific packet delivery that guarantees maximum/minimum delay requirements of a service, the device includes a transceiver and a control unit operably connected to the transceiver, and the control unit. receives link and node delay information and node buffer resource information on the path, calculates the local delay budget that other nodes must guarantee based on the buffer resource information of the last node, and allows nodes to send packets based on the local delay budget. It can be controlled to transmit, nodes transmit packets within the local delay budget, and the last node ultimately guarantees the remaining delay budget.

According to various embodiments of the present disclosure, in the SDN controller for time-specific packet delivery that guarantees the maximum/minimum delay requirements of the service, the SDN controller includes a transceiver and a control unit operably connected to the transceiver; , The control unit receives link and node delay information and node buffer resource information on the path, calculates the local delay budget that other nodes must guarantee based on the buffer resource information of the last node, and nodes based on the local delay budget. You can control to transmit packets, control nodes to transmit packets within the local delay budget, and have the last node ultimately guarantee the remaining delay budget.

The apparatus and method according to various embodiments of the present disclosure ensure the on-time performance required by the service by having each node forward according to a clear local delay budget that can satisfy service delay requirements based on clear resource information. , by enabling packet scheduling at intermediate nodes with a margin larger than the delay requirements of the service, the packet scheduling burden on the nodes can be reduced while strictly complying with the upper and lower bound requirements of the service.

In addition, the apparatus and method according to various embodiments of the present disclosure increase the difference between the local delay budget upper and lower limits of each node as much as possible even when the difference between the upper and lower limits of the service delay requirement is very small or even the same, so that each node This allows the packet scheduling burden to be reduced.

The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below. will be.

Figure 1 illustrates problems with the prior art CQF method according to various embodiments of the present disclosure.
Figure 2 illustrates a problem of the SR-TSN method, which is a prior art, according to various embodiments of the present disclosure.
Figure 3 shows problems with the prior art LBF method according to various embodiments of the present disclosure.
Figure 4 illustrates a resource-based on-time forwarding method according to an embodiment of the present disclosure.
Figure 5 may illustrate the operation of a resource-based on-time forwarding method according to various embodiments of the present disclosure.
FIG. 6 illustrates an operation of expanding a resource-based on-time forwarding scheme according to various embodiments of the present disclosure.
Figure 7 shows a method of operating an SDN controller according to an embodiment of the present disclosure.
Figure 8 shows a configuration diagram of an SDN controller in a communication system according to various embodiments of the present disclosure.

Terms used in the present disclosure are merely used to describe specific embodiments and may not be intended to limit the scope of other embodiments. Singular expressions may include plural expressions, unless the context clearly indicates otherwise. Terms used herein, including technical or scientific terms, may have the same meaning as generally understood by a person of ordinary skill in the technical field described in this disclosure. Among the terms used in this disclosure, terms defined in general dictionaries may be interpreted to have the same or similar meaning as the meaning they have in the context of related technology, and unless clearly defined in this disclosure, have an ideal or excessively formal meaning. It is not interpreted as In some cases, even terms defined in the present disclosure cannot be interpreted to exclude embodiments of the present disclosure.

In various embodiments of the present disclosure described below, a hardware approach method is explained as an example. However, since various embodiments of the present disclosure include technology using both hardware and software, the various embodiments of the present disclosure do not exclude software-based approaches.

Hereinafter, the present disclosure relates to a method and device for resource-based on-time packet delivery. Specifically, the present disclosure provides a technology for delivering time-specific packets in packet networks such as Ethernet, IP, MPLS, etc., so that the total delay experienced while service traffic is delivered through the network can satisfy the delay time requirements of the service. Explain.

In the following description, terms referring to signals, terms referring to channels, terms referring to control information, terms referring to network entities, terms referring to device components, etc. are used for convenience of explanation. This is exemplified. Accordingly, the present disclosure is not limited to the terms described below, and other terms having equivalent technical meaning may be used.

Related technologies for ensuring a quantified target time related to this disclosure include time-sensitive forwarding technology defined by IEEE 802.1 TSN (Time-Sensitive Networking) and IETF's DetNet (Deterministic Networking). Methods defined in TSN include TAS (Time Aware Shaper), which controls the queue output time based on time synchronization, and CQF (Cyclic Queuing and forwarding) using this. However, this method has a problem in that the end-to-end delay time of the network cannot be controlled as desired because the maximum delay and delay deviation are determined by the time interval (TI) determined according to the traffic characteristics of the service. For example, Figure 1 details the problems with the CQF scheme.

Figure 1 illustrates problems with the prior art CQF method according to various embodiments of the present disclosure.

Referring to Figure 1, in the CQF method, the maximum delay and delay deviation are determined by the time interval value determined according to traffic properties and the number of hops on the path. For example, if TI is 125 μs, each node stores and transmits traffic by crossing two queues every 125 μs, so the maximum end-to-end delay of the traffic is (number of nodes + 1) x 125 μs, and the minimum The delay is (number of nodes - 1) x 125 μs, and the jitter is 250 μs (2 x 125 μs). However, this value is determined by the TI value determined according to the characteristics of the traffic, and is unrelated to the maximum delay and delay deviation required by the service. Therefore, the CQF method has limitations in satisfying service delay requirements. The T-CQF (Tagged CQF) method being discussed in DetNet to improve TSN's CQF method to operate in a wide area network also has the same limitations.

Another method being discussed in DetNet is the SR-TSN method, which extends Segment Routing (SR) technology to specify a deadline by which packets must be transmitted from each node. However, although this can satisfy the maximum delay requirement of the service, it does not guarantee on-time. For example, Figure 2 explains the problems of the SR-TSN scheme in detail.

Figure 2 illustrates a problem of the SR-TSN method, which is a prior art, according to various embodiments of the present disclosure.

Referring to Figure 2, SR-TSN appropriately distributes a delay budget to each node, which is the maximum delay requested by the user minus the minimum fixed delay on the path, and each node forwards packets within the given budget, thereby maintaining the network If congestion does not occur, packets are forwarded with minimal delay, and even if congestion occurs, maximum delay is guaranteed. Therefore, the on-time performance that this method can guarantee is determined by the maximum delay requirement of the service and the minimum fixed delay on the path, as shown in the example in FIG. 2, so on-time performance cannot be guaranteed as required by the service.

The recently announced delay-based forwarding method can, in principle, deliver traffic at a time that exactly suits service requirements. This method calculates the traffic transmission time to ensure maximum/minimum delay based on the service delay requirement, the number of nodes remaining from each node to the endpoint, the time expected to be required to transmit the packet, and the time taken to date. . This method has the advantage of being able to satisfy service requirements even if nodes other than the last node, which is responsible for ensuring on-time, output packets with a delay time different from the calculated delay budget. However, since this method does not know the resource status of the last node, in reality it must operate within the calculated delay budget. This limitation causes the problem that as the delay deviation requirements of the service are small, each node must operate according to a much smaller budget. For example, Figure 3 details the problems with the LBF method.

Figure 3 shows problems with the prior art LBF method according to various embodiments of the present disclosure.

Referring to Figure 3, in order to provide on-time forwarding, LBF calculates the maximum/minimum delay requirements of the service (SLO_UB, SLO_LB), the time taken to date (e_delay), the number of nodes remaining to the destination (to_hops), and the remaining path. Calculate the local delay budget for each node based on the minimum delay time (to_delay) expected to take. As in example 1 in Figure 3, if all nodes deliver packets within the calculated local delay upper bound (UB) and lower bound (Lower Bound, LB), the delay time to the destination meets the service requirements. You can be satisfied. However, if the actual delay time of each node deviates from the local delay budget, as shown in Example 2 to Example 3 of FIG. 3, the service requirements cannot be satisfied. As in Example 2, if nodes N1, N2, and N3 deliver packets with a delay greater than the calculated delay budget, the total delay time will be greater than the maximum delay requirement of the service even if node N4 delivers the packet without delay.

Additionally, as in Example 3, when nodes N1, N2, and N3 forward packets with a delay less than the calculated delay budget, node N4's calculated delay budget (3.4 ms) exceeds node N4's maximum delay limit (3 ms), The total delay time will be less than the minimum delay requirement of the service. Therefore, in principle, the LBF method can satisfy service delay requirements even if each node exceeds the calculated budget, but in practice, each node must exactly adhere to the calculated budget because it is unknown what the allowable budget exceedance range is. Just do it.

This limitation is that when the upper and lower limits of service delay requirements are the same as in Examples 2 and 3, all intermediate nodes must deliver packets at the exact time without margin, unnecessarily increasing the packet scheduling burden on all nodes. do.

The present disclosure is intended to solve the limitations of on-time forwarding performance, which are problems of the above-described prior technologies, and in particular, to solve the problems of the conventional delay-based forwarding method. Specifically, in solving the problem of the conventional time-definite forwarding technology based on delay, other nodes can calculate the local delay budget using the resource information of the last node or nodes on the path.

Various information required to operate the resource-based on-time forwarding method according to the present disclosure, such as service delay requirements for each node in the network, number of nodes on the path, minimum fixed delay of each node and link, buffer of nodes Resource information, etc. can be provided in various ways. It can be collected through an SDN-based centralized control/management controller, or it can be collected through a distributed signaling protocol. The information required for on-time forwarding identified based on the collected resource and delay information is provided in a packet header through various packet formats, and the necessary information can be updated after necessary processing at each node. Alternatively, it may be provided through packet overhead on the data plane, such as segment routing, which is advantageous in terms of network scalability. The following is an embodiment of the present disclosure, and it is assumed that information necessary for operation is provided in a packet header and that each node updates related information after packet processing for on-time forwarding.

Figure 4 illustrates a resource-based on-time forwarding method according to an embodiment of the present disclosure.

Referring to Figure 4, the following parameters are defined.

- SLO_LB: User latency requirement lower bound

- SLO_UB: User latency requirement upper bound

- L[i]_Dmin: Link[i] minimum fixed delay

- N[i]_Dmin: node[i] minimum fixed delay

- E2E_Dmin: Minimum fixed delay sum of the end-to-end path (∑L_Dmin + ∑N_Dmin)

- E2E_LB: End-to-end path delay budget lower bound (SLO_LB - E2E_Dmin)

- E2E_UB: End-to-end path delay budget upper bound (SLO_UB - E2E_Dmin)

- N_Dmax: Maximum delay that can be provided by the node's buffer resources.

- LN_Dmax: Maximum delay that can be provided by the buffer resources of the last node

- N[i]_LB: Node[i] delay budget lower bound (1≤i≤n-1)

- N[i]_UB: Node[i] delay budget upper limit (1≤i≤n-1)

- R_LB: Remaining delay budget lower bound (last node's delay budget lower bound)

- R_UB: Remaining delay budget upper bound (delay budget upper bound of the last node)

Referring to Figure 4, a series of packets requiring guarantees of both minimum (SLO_LB) and maximum (SLO_UB) delay times are defined as on-time flows, and E2E_Dmin and N_Dmax of each node and the last node are processed through the SDN controller or protocol. The available LN_Dmax can be collected. E2E_Dmin may be the sum of the minimum fixed delays of all links and nodes existing on the path between the transmitting end and the receiving end.

The minimum link delay may be calculated by comparing packet transmission and reception times between nodes that are time-synchronized through the IEEE 1588 time synchronization method, or may be measured through a separate delay measurement method.

The node minimum delay is a fixed delay required for all packet processing except queuing delay, such as packet encoding/decoding and packet overhead lookup, and may be a value determined depending on the node's implementation.

N_Dmax and LN_Dmax refer to the time that the intermediate node and the last node can buffer as much as possible. The maximum delay calculated based on the properties of the service flow (bandwidth, packet size, etc.) and buffer resources, excluding the node's minimum fixed delay. It could be time.

The on-time forwarding method according to an embodiment of the present disclosure sets the lower limit (N[i]_LB) and upper limit of the delay budget that each node must guarantee based on the collected E2E_Dmin, N_Dmax, LN_Dmax and the SLO_LB and SLO_UB requested by the user. (N[i]_LB), and the delay budget lower bound (R_LB) and upper bound (R_UB) that the last node must guarantee can be determined.

According to one embodiment, it is calculated as Equation 1 to Equation 4.

Here, N[i]_D may mean the actual delay time of the ith node.

Equation 1 to Equation 2 may be the simplest calculation example in which the delay budget of the last nodes is distributed uniformly to each node. Additionally, according to one embodiment, the corresponding N[i]_LB and N[i]_UB may naturally mean a value smaller than N_Dmax.

According to another embodiment, considering the N_Dmax of each node, the total of N[i]_LB can be distributed differently so that the total of N[i]_LB is E2E_LB - LN_Dmax and the total of N[i]_UB is E2E_UB.

According to one embodiment, a method of providing an on-time forwarding function based on the calculated N[i]_LB, N[i]_UB, R_LB, and R_UB is as follows.

Except for the last node, other nodes (N[i], 1≤i≤n-1) have a local delay budget calculated and delivered based on delay and buffer information through a centralized controller or signaling protocol, i.e., local delay budget. QoS operation is performed to ensure that packets are forwarded within the delay budget lower limit (N[i]_LB) and upper limit (N[i]_UB), and the actual delay time (N[i]_D) is determined according to the packet processing results. You can forward packets in a packet.

According to one embodiment, as a method of conveying the actual delay time of a node, the remaining delay budget (R_UB, R_LB) of the packet header is initially specified as the same value as the end-to-end path delay budget (E2E_UB, E2E_LB), and each node receives the packet. When forwarding, the remaining delay budget information in the packet header coming to the last node can become the local delay budget of the last node by updating to the value minus the actual delay time. The last node can perform QoS operations so that packets are forwarded within the remaining delay budget lower limit (R_LB) and upper limit (R_UB). If the local delay budget upper limit of the last node is greater than the maximum delay (LN_Dmax) that the last node buffer can provide, LN_Dmax can be the delay upper limit of the last node.

Figure 5 may illustrate the operation of a resource-based on-time forwarding method according to various embodiments of the present disclosure. Figure 5 assumes the same network configuration and service requirements as Figure 3 to compare the differences between the present disclosure and the conventional LBF method.

Referring to FIG. 5, Example 1 of FIG. 5 shows a case where the upper and lower limits of service delay requirements are different. It can be seen that all nodes forward packets within the calculated local delay budget, and the total delay time satisfies the delay requirements of the service.

According to an embodiment of the present disclosure, Example 2 of FIG. 5 shows improved characteristics compared to the conventional LBF method. Even when the upper and lower limits of the service delay requirement are the same, the present disclosure has a local delay budget upper limit of 1.67ms and a lower limit of 0.67ms, so QoS operation can be comfortably performed with a margin of 1ms. On the other hand, in the conventional LBF method, the upper and lower limits of the local delay budget have the same value, as shown in Examples 2 and 3 of FIG. 3. Therefore, in the conventional LBF method, unless there is additional information, all nodes must perform QoS operations to ensure that packets are forwarded at the correct time.

According to one embodiment, the resource-based on-time forwarding method according to the present disclosure defines the remaining delay budget (R_UB, R_LB) as the value minus the actual delay time of the last node when the last node delivers the packet to the destination (receiving end). By doing so, the receiving end can use it as data needed to internally process the service in the application.

FIG. 6 illustrates an operation of expanding a resource-based on-time forwarding scheme according to various embodiments of the present disclosure. Specifically, in the resource-based on-time forwarding method according to the present disclosure shown in FIG. 4, the last node can be expanded into the network as shown in FIG. 6. Here, the network can be a network that can forward packets within a given delay budget, like the last node in Figure 4, and the maximum delay time that the network can provide can be determined.

Figure 7 shows a method of operating an SDN controller according to an embodiment of the present disclosure.

Referring to FIG. 7, the SDN controller may receive resource information of the last node from the last node (701).

According to one embodiment, the resource information of the last node may be determined based on the buffer size allocated to the service and the properties of the service. The local delay budget can be determined based on the delay requirements of the service and the maximum delay time of the last node.

According to one embodiment, the service properties may include information about bandwidth or packet size.

According to one embodiment, the last node may be a network that can forward packets within a given delay budget and for which a maximum delay time can be determined.

According to one embodiment, the local delay budget may be identified based on service delay requirements and the total time delay budget spent in the network.

The SDN controller may identify the local delay budget based on the resource information of the last node (703).

According to one embodiment, if the local delay budget of the last node is greater than the maximum delay that the last node can provide, the maximum delay that the last node can provide may be determined as the upper delay limit of the last node.

Figure 8 shows a configuration diagram of an SDN controller in a communication system according to various embodiments of the present disclosure. The configuration illustrated in FIG. 3 can be understood as the configuration of the SDN controller 800. Hereinafter used ‘…’ wealth', '… Terms such as 'unit' refer to a unit that processes at least one function or operation, and may be implemented as hardware, software, or a combination of hardware and software.

Referring to FIG. 8, the SDN controller 800 may include a communication unit 810, a storage unit 820, and a control unit 830.

The communication unit 810 may perform functions for transmitting and receiving signals through various communication methods, including wired and wireless communication.

Additionally, the communication unit 810 may include multiple transmission and reception paths. In terms of hardware, the communication unit 810 may be composed of digital circuits and analog circuits (eg, radio frequency integrated circuit (RFIC)). Here, the digital circuit and analog circuit can be implemented in one package.

All or part of the communication unit 810 may be referred to as a 'transmitter', a 'receiver', or a 'transceiver'. Additionally, in the following description, transmission and reception performed through wired or wireless means may be used to mean that the processing as described above is performed by the communication unit 810.

The storage unit 820 may store data such as basic programs, applications, and setting information for the operation of the SDN controller. The storage unit 820 may be comprised of volatile memory, non-volatile memory, or a combination of volatile memory and non-volatile memory. Additionally, the storage unit 820 may provide stored data upon request from the control unit 830.

The control unit 830 can control the overall operations of the SDN controller. For example, the control unit 830 may transmit and receive signals through the communication unit 810. Additionally, the control unit 830 can record and read data in the storage unit 820. The control unit 830 can perform the functions of the protocol stack required by communication standards. To this end, the control unit 830 may include at least one processor or microprocessor, or may be part of a processor. Additionally, a portion of the communication unit 810 and the control unit 830 may be referred to as a communication processor (CP).

According to various embodiments, the control unit 830 may control to perform the operations of FIGS. 4 to 7.

According to various embodiments of the present disclosure, a packet delivery method in which a network satisfies the delay requirements of a service is a resource-based on-time method, wherein other nodes calculate a local delay budget using resource information of the last node on the path. It can be delivered as a packet.

According to one embodiment, the buffer resource information of the last node may be delivered as a resource-based on-time packet, with a maximum delay time determined according to the buffer size allocated to the service and the properties of the service.

According to one embodiment, the calculation of the local delay budget may be delivered as a resource-based on-time packet calculated based on the delay requirements of the service and the maximum delay time of the last node.

According to one embodiment, the last node can forward the packet within a given delay budget and forward it as a resource-based on-time packet, which is characterized as a network where the maximum delay time can be determined.

According to various embodiments of the present disclosure, a packet delivery method in which a network satisfies the delay requirements of a service provides a residual delay budget minus the delay requirement of the service and the total delay time spent in the network to the destination (receiving end). It can be characterized as:

According to various embodiments of the present disclosure, the present disclosure provides all link and node delay information, node buffer resource information, etc. on the path through various methods such as a centralized method based on a software defined network (SDN) controller or a distributed method based on a protocol. A process of collecting, a process of calculating the overall maximum/minimum delay budget between end-to-ends to satisfy service requirements based on the collected link and node delay information, and a guarantee for previous nodes based on the buffer resource information of the last node. The process of calculating the maximum/minimum local delay budget, the process of controlling nodes to transmit packets based on the local delay budget, and the final node dividing the local delay budget consumed by previous nodes from the total maximum/minimum delay budget. It may include the process of finally consuming the remaining budget after subtracting the total.

According to various embodiments of the present disclosure, the present disclosure calculates the time required to arrive by transmitting the delivery time of the packet while synchronizing the time of all network nodes as a method of checking the remaining budget that the final node must guarantee. Alternatively, the local budget information consumed by each node can be added to the packet transmitted in a visually asynchronous network and delivered, or the local budget information consumed by each node can be subtracted from the total local budget and delivered.

According to various embodiments of the present disclosure, the SDN controller-based centralized method has the controller collect information on all network nodes, and when a service is requested, each node sends packets according to a budget calculated based on the information collected by the controller. It is responsible for the function of setting to transmit, and in the protocol-based distributed method, each node transmits delay and resource information to the final node when a service is requested through the protocol, and the final node transmits delay and resource information based on the information collected along with the service request. It can be responsible for setting packets to be transmitted according to the calculated local budget.

Methods according to embodiments described in the claims or specification of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

When implemented as software, a computer-readable storage medium that stores one or more programs (software modules) may be provided. One or more programs stored in a computer-readable storage medium are configured to be executable by one or more processors in an electronic device (configured for execution). One or more programs include instructions that cause the electronic device to execute methods according to embodiments described in the claims or specification of the present disclosure.

These programs (software modules, software) may include random access memory, non-volatile memory, including flash memory, read only memory (ROM), and electrically erasable programmable ROM. (electrically erasable programmable read only memory, EEPROM), magnetic disc storage device, compact disc-ROM (CD-ROM), digital versatile discs (DVDs), or other types of disk storage. It can be stored in an optical storage device or magnetic cassette. Alternatively, it may be stored in a memory consisting of a combination of some or all of these. Additionally, multiple configuration memories may be included.

In addition, the program may be distributed through a communication network such as the Internet, an intranet, a local area network (LAN), a wide area network (WAN), or a storage area network (SAN), or a combination thereof. It may be stored on an attachable storage device that is accessible. This storage device can be connected to a device performing an embodiment of the present disclosure through an external port. Additionally, a separate storage device on a communication network may be connected to the device performing an embodiment of the present disclosure.

In the specific embodiments of the present disclosure described above, elements included in the disclosure are expressed in singular or plural numbers depending on the specific embodiment presented. However, singular or plural expressions are selected to suit the presented situation for convenience of explanation, and the present disclosure is not limited to singular or plural components, and even components expressed in plural may be composed of singular or singular. Even expressed components may be composed of plural elements.

Meanwhile, in the detailed description of the present disclosure, specific embodiments have been described, but of course, various modifications are possible without departing from the scope of the present disclosure. Therefore, the scope of the present disclosure should not be limited to the described embodiments, but should be determined not only by the scope of the patent claims described later, but also by the scope of this patent claim and equivalents.

Claims (20)

In a time-specific packet delivery method that guarantees the maximum/minimum delay requirements of the service,
A process of receiving link and node delay information and node buffer resource information on the path;
The process of calculating the local delay budget that other nodes must guarantee based on the buffer resource information of the last node,
A process of controlling nodes to transmit packets based on the local delay budget;
A method of controlling nodes to transmit packets within the local delay budget and allowing the last node to finally guarantee the remaining delay budget. In claim 1,
A method in which the buffer resource information of the last node is determined based on the buffer size allocated to the service and the attributes of the service. In claim 1,
The process of controlling nodes to transmit packets based on the local delay budget is,
A method that involves setting explicit upper and lower bounds on the local delay budget that each node must guarantee. In claim 3,
The process of controlling nodes to transmit packets based on the local delay budget is,
A process of collecting buffer resource information of all nodes,
A method including the process of calculating a local delay budget for each node that does not exceed the delay time that can be provided based on the buffer resources of each node. In claim 4,
The local delay budget is determined based on the total network delay and the remaining delay time minus the delay that the last node can guarantee to ensure service delay requirements. In claim 1,
The process of controlling the last node to finally guarantee the remaining delay budget is,
A process of transmitting delay information actually consumed by each node to the last node when nodes transmit packets within the upper and lower limits of the local delay budget;
A process of identifying the remaining delay budget based on actual delay information received from previous nodes;
A method comprising setting the identified remaining delay budget as the local delay budget of the last node. In claim 6,
When the upper limit of the remaining delay is greater than the maximum delay that can be provided based on the buffer resources of the last node, a method of determining the upper limit of the local delay budget of the last node as the maximum delay that the last node can provide. The method of claim 2, wherein the service properties include information on a packet delivery period, the number of packets delivered within the period, and packet size. In the device for time-sensitive packet delivery that guarantees the maximum/minimum delay requirements of a service, the device includes:
Transmitter and receiver,
Comprising a control unit operably connected to the transceiver unit,
The control unit,
Receive link and node delay information and node buffer resource information on the path,
Calculate the local delay budget that other nodes must guarantee based on the buffer resource information of the last node,
Control nodes to transmit packets based on the local delay budget,
A device that controls nodes to transmit packets within the local delay budget and the last node to finally guarantee the remaining delay budget. In claim 9,
A device in which the buffer resource information of the last node is determined based on the buffer size allocated to the service and the attributes of the service. The method of claim 9, wherein the control unit,
A device that sets upper and lower limits of a clear local delay budget that each node must guarantee in order to control nodes to transmit packets based on the local delay budget. The method of claim 11, wherein the control unit
In order to control nodes to transmit packets based on the local delay budget,
Collect buffer resource information of all the nodes,
A device that calculates the local delay budget of each node that does not exceed the delay time that can be provided based on the buffer resources of each node. In claim 12,
The local delay budget is determined based on the total network delay and the remaining delay time minus the delay that can be guaranteed by the last node to ensure service delay requirements. The method of claim 9, wherein the control unit,
In order for the last node to finally guarantee the remaining delay budget,
When nodes transmit packets within the upper and lower limits of the local delay budget, the delay information actually consumed by each node is transmitted to the last node,
Identify the remaining delay budget based on actual delay information received from previous nodes,
Apparatus for setting the identified remaining delay budget to the local delay budget of the last node. In claim 14,
If the upper limit of the remaining delay is greater than the maximum delay that can be provided based on the buffer resources of the last node, the device determines the upper limit of the local delay budget of the last node as the maximum delay that the last node can provide. The method of claim 10, wherein the service properties include information on a packet delivery period, the number of packets delivered within the period, and packet size. In the SDN controller for time-specific packet delivery that guarantees the maximum/minimum delay requirements of the service, the SDN controller includes:
Transmitter and receiver,
Comprising a control unit operably connected to the transceiver unit,
The control unit,
Receive link and node delay information and node buffer resource information on the path,
Calculate the local delay budget that other nodes must guarantee based on the buffer resource information of the last node,
Control nodes to transmit packets based on the local delay budget,
A device that controls nodes to transmit packets within the local delay budget and the last node to finally guarantee the remaining delay budget. In claim 17,
A device in which the buffer resource information of the last node is determined based on the buffer size allocated to the service and the attributes of the service. The method of claim 17, wherein the control unit:
A device that sets upper and lower limits of a clear local delay budget that each node must guarantee in order to control nodes to transmit packets based on the local delay budget. In the method of operating an SDN controller to deliver time-specific packets that guarantee the maximum/minimum delay requirements of the service,
A process of receiving link and node delay information and node buffer resource information on the path;
The process of calculating the local delay budget that other nodes must guarantee based on the buffer resource information of the last node,
A process of controlling nodes to transmit packets based on the local delay budget;
A method of controlling nodes to transmit packets within the local delay budget and allowing the last node to finally guarantee the remaining delay budget.

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