Communication network bandwidth resource visual dynamic allocation method and system based on SDN (Software Defined Network)

Abstract

The invention discloses a communication network bandwidth resource visualized dynamic allocation method and system based on an SDN, and relates to the technical field of communication networks, and the method comprises the steps: obtaining the channel interference intensity, the spectrum occupancy rate and the service flow priority data of each node in a wireless network based on a southbound interface of an SDN controller, and obtaining the channel interference intensity, the spectrum occupancy rate and the service flow priority data of each node through a channel resource dynamic allocation table; generating a multi-dimensional resource view; according to the multi-dimensional resource view, multi-level coverage domains of the wireless network are divided, the service load level of each coverage domain is identified, and a pre-allocation scheme of cross-domain bandwidth resources is generated; and executing a pre-allocation scheme of cross-domain bandwidth resources by using a northbound interface of the SDN controller, and adjusting bandwidth allocation parameters of each coverage domain. According to the invention, visual monitoring, accurate division and flexible scheduling of the network resource state are realized, and the utilization efficiency of network bandwidth resources is remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of communication networks, and more specifically, to a method and system for visualizing and dynamically allocating communication network bandwidth resources based on SDN. Background Art

[0002] With the rapid development of information technology and the increasing richness of Internet applications, the data traffic carried by communication networks has grown exponentially, posing higher requirements for the efficient management of network bandwidth resources. Under the traditional network architecture, bandwidth resource allocation usually adopts a static configuration method, which cannot adapt to the dynamically changing network traffic requirements. Software-Defined Network (SDN), as a new generation of network architecture, realizes network programmability and centralized control by separating the control plane from the data plane, providing a new technical basis for the refined management of bandwidth resources. The SDN controller can obtain the whole network topology and traffic information, and theoretically can achieve the global optimal configuration of network resources. Therefore, the bandwidth resource management based on the SDN architecture has become a hot research direction in current network technologies.

[0003] At present, the bandwidth resource allocation technology based on SDN has developed to a certain extent, mainly including policy-based allocation methods, QoS-based allocation methods, and traffic prediction-based allocation methods, etc. The policy-based allocation method divides the priorities of different service flows through preset rules and allocates bandwidth resources according to the priority levels; the QoS-based allocation method dynamically adjusts the bandwidth allocation ratio according to the service quality requirements; the traffic prediction-based allocation method predicts future traffic demands through historical data analysis and machine learning algorithms and conducts bandwidth planning in advance. In terms of resource visualization, existing technologies mainly provide basic visualization functions such as network topology display, link utilization statistical charts, traffic heat maps, etc., to help network administrators understand the network status. These technologies have improved the utilization efficiency of bandwidth resources to a certain extent and reduced the complexity of network management.

[0004] However, there are still many deficiencies in the existing bandwidth resource allocation technologies: the existing methods mainly focus on the resource management of a single dimension of the communication network, lacking a multi-level flow table acquisition and processing mechanism for network node data and being unable to achieve all-round visual monitoring of the wireless network resource status; at the same time, the existing methods generally lack a cross-network domain bandwidth resource collaborative allocation mechanism, making it difficult to achieve the unified scheduling and optimization of global resources, easily forming bandwidth resource "islands" and reducing the overall network performance; in addition, the existing SDN-based bandwidth resource allocation methods mainly rely on algorithm automation processing, lacking an intuitive visual display of the network bandwidth resource allocation status, and network administrators cannot intuitively understand the whole network resource allocation situation and flexibly adjust according to actual needs, resulting in insufficient accuracy and flexibility of resource management. These problems seriously restrict the optimal configuration and efficient utilization of communication network bandwidth resources.

[0005] In the related art, no effective solution has been proposed for the problems yet. Summary of the Invention

[0006] In view of the problems in the related art, the present invention provides a method and system for visual dynamic allocation of communication network bandwidth resources based on SDN, which has the advantages of visual monitoring of network resource status, accurate division, and flexible scheduling, thereby solving the problems of incomplete perception of network resource status, inaccurate resource division, and inflexible allocation in the prior art.

[0007] For this reason, the specific technical solutions adopted by the present invention are as follows:

[0008] According to one aspect of the present invention, there is provided a method for visual dynamic allocation of communication network bandwidth resources based on SDN, and the method for visual dynamic allocation of communication network bandwidth resources based on SDN includes:

[0009] S1. Based on the southbound interface of the SDN controller, obtain the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network, and generate a multi-dimensional resource view through the channel resource dynamic allocation table;

[0010] S2. According to the multi-dimensional resource view, divide the multi-level coverage areas of the wireless network, identify the service load levels of each coverage area, and generate a pre-allocation plan for cross-domain bandwidth resources;

[0011] S3. Use the northbound interface of the SDN controller to execute the pre-allocation plan for cross-domain bandwidth resources and adjust the bandwidth allocation parameters of each coverage area.

[0012] Further, based on the southbound interface of the SDN controller, obtaining the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network, and generating a multi-dimensional resource view through the channel resource dynamic allocation table includes:

[0013] S11. Based on the southbound interface of the SDN controller, through the multi-level flow table mechanism of the network switch, obtain the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network in a combined active and passive manner, and generate a channel comprehensive quality index of the node;

[0014] S12. According to the channel comprehensive quality index of each node, obtain the spatial distance relationship and signal coverage intensity between nodes, and establish a channel resource dynamic allocation table;

[0015] S13. Based on the channel resource dynamic allocation table, optimize the channel allocation through the channel switching scheme and generate a multi-dimensional resource view.

[0016] Furthermore, based on the southbound interface of the SDN controller, through the multi-level flow table mechanism of the network switch, the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network are obtained in a combined active and passive manner, and the channel comprehensive quality index of the node is generated, including:

[0017] S111. Establish a connection between the southbound interface of the SDN controller and the network switch, configure the first-level flow table to receive the packet statistical information reported by the switch, and establish an initial traffic matrix between nodes through the passive listening mechanism;

[0018] S112. According to the initial traffic matrix, configure the second-level flow table for active probe packet injection, obtain the channel interference intensity and spectrum occupancy rate, and generate the real-time traffic change trend through differential calculation technology;

[0019] S113. Based on the real-time traffic change trend, configure the third-level flow table for service traffic priority marking, and perform hierarchical weighted calculation on the service traffic data to output the channel comprehensive quality index of the node.

[0020] Furthermore, according to the channel comprehensive quality index of each node, obtain the spatial distance relationship and signal coverage intensity between nodes, and establish a dynamic channel resource allocation table, including:

[0021] S121. Based on the channel comprehensive quality index of the node, determine the signal transmission power and receiving sensitivity of each node, and generate the actual communication distance between nodes according to the signal strength attenuation value;

[0022] S122. According to the actual communication distance between nodes, divide the signal overlapping coverage area and the weak coverage area, and determine the available channel number in each area based on the signal interference degree;

[0023] S123. Based on the available channel number in each area, count the spectrum resource occupancy of the currently accessed terminals, and establish a dynamic channel resource allocation table according to the bursty characteristics of the service traffic.

[0024] Furthermore, generating the actual communication distance between nodes according to the signal strength attenuation value includes:

[0025] When the channel comprehensive quality index of a node is higher than the first threshold, reduce the transmission power to the minimum power limit; when the channel comprehensive quality index of the node is between the first threshold and the second threshold, keep the current transmission power unchanged; when the channel comprehensive quality index of the node is between the second threshold and the third threshold, increase the transmission power in steps; when the channel comprehensive quality index of the node is lower than the third threshold, increase the transmission power to the maximum power limit; calculate the signal strength attenuation value according to the difference between the signal strength measured by the receiving node and the transmission power of the sending node; determine the actual communication distance between nodes as the transmission distance corresponding to when the received signal strength is equal to the received sensitivity.

[0026] Furthermore, based on the channel resource dynamic allocation table, optimize the channel allocation through the channel switching scheme, and generate a multi-dimensional resource view including:

[0027] S131. According to the channel resource dynamic allocation table, calculate the spectrum utilization efficiency in each area, identify the spectrum resource limited areas, and generate a frequency occupancy distribution map in combination with the matching degree of channel quality and service requirements;

[0028] S132. Based on the distribution of the spectrum resource limited areas, determine the possibility of channel reuse, formulate a channel switching scheme according to the inter-channel interference level, and at the same time, form a spatial coverage blind area map in combination with the spatial distance relationship and signal coverage strength between nodes;

[0029] S133. When channel congestion occurs, adjust the available channel allocation in each area through the channel switching scheme, and construct a service traffic priority distribution map based on the adjusted service traffic distribution;

[0030] Among them, the multi-dimensional resource view includes a frequency occupancy distribution map, a spatial coverage blind area map, and a service traffic priority distribution map.

[0031] Furthermore, according to the multi-dimensional resource view, divide the multi-level coverage areas of the wireless network, identify the service load levels of each coverage area, and generate a pre-allocation scheme for cross-domain bandwidth resources including:

[0032] S21. Based on the frequency occupancy distribution map and the spatial coverage blind area map in the multi-dimensional resource view, divide the wireless network into a core coverage area, an edge coverage area, and a relay coverage area, and establish a real-time shared channel for the resource status between domains;

[0033] S22. Generate a resource pool containing the total available bandwidth of each coverage area according to the cross-domain resource data obtained from the inter-domain resource status shared channel, and identify the service load levels of each coverage area through the service traffic priority distribution map;

[0034] S23. Calculate the bandwidth demand and allocable amount for each coverage area based on the service load level of each coverage area, and determine the pre-allocation plan for cross-domain bandwidth resources.

[0035] Further, divide the wireless network into a core coverage area, an edge coverage area, and a relay coverage area, and establish a real-time sharing channel for inter-domain resource status, including: determining the spectrum resource index of each area in the frequency occupancy distribution map based on the product of the channel occupancy rate and the number of available channels within the area; obtaining the coverage quality index of each area in the spatial coverage blind area map based on the product of the average signal strength and the ratio of the non-blind area within the area; mapping the spectrum resource index and the coverage quality index of the area to be divided to a two-dimensional evaluation matrix, and determining the coverage area type of the area to be divided based on the quadrant distribution in the two-dimensional evaluation matrix, and establishing a regular sharing channel for inter-domain resource status; where the horizontal axis of the two-dimensional evaluation matrix represents the spectrum resource index, and the vertical axis of the two-dimensional evaluation matrix represents the coverage quality index.

[0036] Further, determining the coverage area type of the area to be divided based on the quadrant distribution in the two-dimensional evaluation matrix, and establishing a regular sharing channel for inter-domain resource status, including: when the area to be divided is located in the first quadrant, divide it into a core coverage area, and regularly broadcast the total amount of allocable resources to other areas; when the area to be divided is located in the third quadrant, divide it into an edge coverage area, and regularly report the resource demand and service priority to the relay coverage area; when the area to be divided is located in the second or fourth quadrant, divide it into a relay coverage area, and regularly update the inter-domain resource status mapping table and coordinate resource allocation.

[0037] According to another aspect of the present invention, there is also provided a visualization dynamic allocation system for communication network bandwidth resources based on SDN. The visualization dynamic allocation system for communication network bandwidth resources based on SDN includes:

[0038] A resource data calculation unit, configured to obtain the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network based on the southbound interface of the SDN controller, and generate a multi-dimensional resource view through a channel resource dynamic allocation table;

[0039] A coverage area division unit, configured to divide the multi-level coverage areas of the wireless network according to the multi-dimensional resource view, identify the service load level of each coverage area, and generate a pre-allocation plan for cross-domain bandwidth resources;

[0040] A bandwidth scheduling execution unit, configured to execute the pre-allocation plan for cross-domain bandwidth resources by using the northbound interface of the SDN controller, and adjust the bandwidth allocation parameters of each coverage area.

[0041] The beneficial effects of the present invention are:

[0042] (1) The present invention proposes a method for visual dynamic allocation of communication network bandwidth resources based on SDN. It obtains network status data through the southbound interface and generates a multi-dimensional resource view. Based on the resource view, it realizes multi-level coverage area division and bandwidth pre-allocation of the network. Finally, it executes dynamic scheduling and allocation through the northbound interface. The overall solution realizes visual monitoring, precise division, and flexible scheduling of network resource status, significantly improving the utilization efficiency of network bandwidth resources.

[0043] (2) The southbound interface of the SDN controller uses a multi-level flow table mechanism to obtain network node data. The first-level flow table establishes an initial traffic matrix. The second-level flow table obtains channel interference intensity and spectrum occupancy rate. The third-level flow table marks the priority of service traffic and generates a multi-dimensional resource view including a frequency occupancy distribution map, a spatial coverage blind area map, and a service traffic priority distribution map based on the channel resource dynamic allocation table, realizing all-round visual monitoring of the status of wireless network resources and overcoming the technical problem of incomplete perception of network resource status in the prior art.

[0044] (3) By mapping the spectrum resource index and the coverage quality index to a two-dimensional evaluation matrix, multi-level coverage area division of the wireless network is realized based on quadrant distribution, and a real-time sharing channel for inter-domain resource status is established, enabling the core coverage area to regularly broadcast the total amount of allocable resources, the edge coverage area to regularly report resource requirements, and the relay coverage area to regularly update the resource status mapping table, making the division of network resources more accurate and reasonable. At the same time, through the pre-allocation scheme of cross-domain bandwidth resources, the utilization efficiency of network resources is improved.

[0045] (4) The northbound interface of the SDN controller executes dynamic scheduling and allocation of bandwidth resources, generates a bandwidth scheduling instruction set based on the pre-allocation scheme and converts it into specific allocation parameters, and uses a dynamic bandwidth adjuster to adjust the bandwidth allocation ratio of each coverage area in real time. When the service in the core coverage area increases, the reservation ratio is increased. When the edge coverage area needs it, it can borrow resources from the relay domain, and a resource locking mechanism is used to ensure the stability of the allocation, solving the technical defect of fixed network resource allocation and difficult dynamic adjustment in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0047] Figure 1 is a schematic flowchart of a method for visual dynamic allocation of communication network bandwidth resources based on SDN according to an embodiment of the present invention;

[0048] Figure 2 It is a principle block diagram of a visualization dynamic allocation system for communication network bandwidth resources based on SDN according to an embodiment of the present invention. Detailed implementation manners

[0049] To further illustrate each embodiment, the present invention provides accompanying drawings, which are part of the disclosure of the present invention. They are mainly used to illustrate the embodiments and can cooperate with the relevant descriptions in the specification to explain the operation principle of the embodiments. With reference to these contents, those of ordinary skill in the art should be able to understand other possible implementation manners and the advantages of the present invention. The components in the figures are not drawn to scale, and similar component symbols are usually used to represent similar components.

[0050] According to an embodiment of the present invention, there are provided a visualization dynamic allocation method and system for communication network bandwidth resources based on SDN.

[0051] Now, the present invention will be further described in conjunction with the accompanying drawings and specific implementation manners. As Figure 1 shown, according to an embodiment of the present invention, there is provided a visualization dynamic allocation method for communication network bandwidth resources based on SDN. The visualization dynamic allocation method for communication network bandwidth resources based on SDN includes:

[0052] S1. Based on the southbound interface of the SDN controller, obtain the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network, and generate a multi-dimensional resource view through a channel resource dynamic allocation table;

[0053] S2. According to the multi-dimensional resource view, divide the multi-level coverage areas of the wireless network, identify the service load levels of each coverage area, and generate a pre-allocation plan for cross-domain bandwidth resources;

[0054] S3. Use the northbound interface of the SDN controller to execute the pre-allocation plan for cross-domain bandwidth resources and adjust the bandwidth allocation parameters of each coverage area.

[0055] In one embodiment, based on the southbound interface of the SDN controller, obtaining the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network, and generating a multi-dimensional resource view through a channel resource dynamic allocation table includes:

[0056] S11. Based on the southbound interface of the SDN controller, through the multi-level flow table mechanism of the network switch, obtain the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network in a combined active and passive manner, and generate a channel comprehensive quality index of the node;

[0057] S12. Obtain the spatial distance relationship and signal coverage intensity between nodes according to the channel comprehensive quality index of each node, and establish a dynamic channel resource allocation table;

[0058] S13. Based on the dynamic channel resource allocation table, optimize channel allocation through a channel switching scheme and generate a multi-dimensional resource view.

[0059] Specifically, the multi-dimensional resource view includes a frequency occupancy distribution map, a spatial coverage blind area map, and a service traffic priority distribution map.

[0060] In one embodiment, based on the southbound interface of the SDN controller, through the multi-level flow table mechanism of the network switch, obtain the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network in a combined active and passive manner, and generate the channel comprehensive quality index of the node, including:

[0061] S111. Establish a connection between the SDN controller and the network switch based on the southbound interface, configure the first-level flow table to receive the packet statistical information reported by the switch, and establish an initial traffic matrix between nodes through a passive listening mechanism;

[0062] Specifically, the SDN controller sends a connection request message to the network switch through the southbound interface. The message contains the IP address, port number, supported protocol version number, and controller identifier of the controller. After receiving the request, the switch returns a confirmation message containing the device identifier, port number, and flow table capacity. After several handshakes (set to three times in this example), a TCP long connection is established. The controller stores the information of the connected switch in the switch management table. The table entries of the management table include the switch identifier, IP address, port mapping relationship, and connection status flag bit.

[0063] Specifically, the initial traffic matrix between nodes is a two-dimensional array of N×N (N is the number of nodes in the network). The element F in the matrix ij represents the traffic volume from node i to node j. To obtain this matrix, the SDN controller first sends a first-level flow table configuration instruction to the connected switch. In the present invention, the first-level flow table includes exact match fields {source MAC address, destination MAC address, input port number, protocol type} and statistical fields {packet counter, byte counter, flow table entry duration}, and also includes action fields {update statistics, normal forwarding}, which are used to record the number of packets, total number of bytes, and duration passing through each port of the switch.

[0064] Specifically, the SDN controller actively reads the statistical field information in the first-level flow tables of each switch every preset sampling period (set to 10 seconds in this embodiment) through a passive listening mechanism. For each flow table entry, the controller determines the corresponding node pair (i, j) based on its source MAC address and destination MAC address, and calculates the initial traffic value between the node pair according to the element formula in the initial traffic matrix. After completing the statistics of all flow table entries, the controller updates the entire traffic matrix and stores the matrix data in the traffic database of the controller as the basic data for subsequent traffic analysis.

[0065] Specifically, the expression of the element in the initial traffic matrix is:

[0066] F ij = (B cur - B pre ) / (T cur - T pre );

[0067] In the formula, B cur represents the current byte count; B pre represents the previous byte count; T cur represents the current timestamp; T pre represents the previous timestamp.

[0068] Specifically, in this embodiment, the wireless network deploys 1 SDN controller (IP address 192.168.1.100) and 4 OpenFlow switches (IP addresses are 192.168.1.101 to 192.168.1.104 respectively) to form a 4-node network. After the controller establishes a connection with the OpenFlow switches through the southbound interface, it records the switch information {switch identifiers 0x11 to 0x14, IP addresses 192.168.1.101 to 192.168.1.104, port mapping relationship 1-24, connection status 1} in the switch management table. The controller configures the first-level flow tables for each OpenFlow switch, and the matching fields of the flow table entries are {source MAC addresses 00:00:00:00:00:01 to 00:00:00:00:00:04, destination MAC addresses 00:00:00:00:00:01 to 00:00:00:00:00:04, input ports 1-24, protocol type 0x0800}, and the statistical fields record the number of data packets, total number of bytes, and duration of each port. During the sampling period from 10:00:00 to 10:00:10, the controller calculates the initial traffic matrix through the formula:

[0069] The initial traffic matrix calculated according to the formula is:

[0070] F = [0, 2560, 1280, 1920;

[0071] 2400, 0, 1600, 2240;

[0072] 1440, 1760, 0, 2080;

[0073] 2080, 1920, 1600, 0];

[0074] Wherein, the unit of the matrix elements is byte / second, and this matrix is stored in the traffic database for subsequent analysis.

[0075] S112. According to the initial traffic matrix, configure the second-level flow table for active probe packet injection, obtain the channel interference intensity and spectrum occupancy rate, and generate the real-time traffic change trend through differential calculation technology;

[0076] Specifically, the SDN controller determines the node pairs that need to be monitored key points according to the traffic values in the initial traffic matrix, and injects probe packets into the paths between these node pairs. The packet header of the probe packet contains fields such as probe type, sequence number, and timestamp, which are used to identify different types of network measurement tasks.

[0077] Specifically, the configuration instructions of the second-level flow table in the present invention include match fields {probe packet identifier, probe type, sequence number range} and action fields {modify packet header information, specify output port, report to controller}; among them, the probe packet identifier is used to distinguish ordinary data packets and probe packets, the probe type is used to distinguish channel interference intensity measurement and spectrum occupancy rate measurement, and the sequence number range is used to track the transmission process of the probe packet.

[0078] Specifically, after the receiving node receives the probe packet, corresponding measurements are performed according to the probe type. In the present invention, for the channel interference intensity D i measurement, calculate the ratio of the received signal strength to the background noise strength; for the spectrum occupancy rate P i measurement, calculate the ratio of the number of effective data packets received per unit time to the theoretical maximum number of packets. The measurement results are reported to the SDN controller through OpenFlow messages.

[0079] Specifically, the expression of the channel interference intensity is: D i = RS i / Ns i ; Wherein, RS i represents the received signal strength indication value of node i; Ns i represents the background noise strength of node i; the expression of the spectrum occupancy rate P i is: P i = Nre i / Nma i × 100%; Wherein, Nre iDenote the number of valid data packets received by node i per unit time; Nma i Denote the theoretical maximum number of packets of node i.

[0080] Specifically, in the above embodiment, the SDN controller selects node pairs (i, j) with traffic values greater than 2000 bytes / second for key monitoring according to the initial traffic matrix obtained in S111. The controller configures the second-level flow table on 4 OpenFlow switches, and the matching fields are {probe packet identifier 0xFF, probe types 0x01 (channel interference) and 0x02 (spectrum occupancy), sequence number 0x001 - 0xFFF}. During the detection period from 10:00:10 to 10:00:20, the controller injects 1 probe packet into the selected path every 2 seconds. The receiving node measures that the channel interference intensity is -75dBm / -95dBm = 20dB, and the spectrum occupancy rate is 450 / 500 = 90%. The controller uses differential calculation to process the data of three consecutive sampling periods (10:00:00 - 10:00:30), and obtains that the real-time traffic change trend between node pairs is 25%.

[0081] S113. Based on the real-time traffic change trend, configure the third-level flow table for service traffic priority marking, and perform hierarchical weighted calculation on service traffic data to output the comprehensive channel quality index of the node.

[0082] Specifically, the SDN controller classifies service traffic according to the magnitude of the real-time traffic change trend, and marks it as burst traffic, stable traffic, and low-speed traffic respectively, and assigns corresponding processing priorities to different types of traffic for subsequent traffic scheduling and resource allocation.

[0083] Specifically, the SDN controller classifies service traffic according to the magnitude of the real-time traffic change trend T i . When T i > 30%, it is marked as burst traffic. When 10% ≤ T i ≤ 30%, it is marked as stable traffic. When T i < 10%, it is marked as low-speed traffic; the expression of the traffic change trend T i is:

[0084] T i = (F cur - F pre ) / F pre × 100%;

[0085] In the formula, F cur denotes the traffic value of node i in the current sampling period; F pre denotes the traffic value of node i in the previous sampling period.

[0086] Specifically, the configuration instructions of the third-level flow table in the present invention include matching fields {service type, traffic change range, priority marking} and action fields {modifying priority field, statistical traffic data, reporting to the controller}, which are used to implement the hierarchical marking and data statistics functions of service traffic.

[0087] Specifically, the controller performs weighted calculation on the marked service traffic data. In this embodiment, the weight coefficient of burst traffic is set to 0.5, the weight coefficient of stable traffic is set to 0.3, and the weight coefficient of low-speed traffic is set to 0.2. Multiply the traffic data of different priorities by the preset weight coefficients and sum them to obtain the service traffic weight value W of the node. i Finally, perform normalization processing on the service traffic weight value, channel interference intensity, and spectrum occupancy rate, and calculate to obtain the channel comprehensive quality index of the node; the expression of the channel comprehensive quality index of the node is:

[0088] Q i =α×D i '+β×P i '+γ×W i ';

[0089] In the formula, D i ' represents the normalized channel interference intensity; P i ' represents the normalized spectrum occupancy rate; W i ' represents the normalized service traffic weight value; α represents the channel interference intensity coefficient, which is set to 0.4 in this embodiment; β represents the spectrum occupancy rate coefficient, which is set to 0.3 in this embodiment; γ represents the service traffic coefficient, which is set to 0.3 in this embodiment.

[0090] Specifically, in the above embodiment, the SDN controller marks the service traffic as stable traffic according to the 25% of the measured traffic change trend in S112. The controller configures the third-level flow table on 4 OpenFlow switches, and the matching fields are {service type 0x01, traffic change range 10% - 30%, priority marking 0x02}. In the calculation period from 10:00:20 to 10:00:30, the controller applies a weight coefficient of 0.3 to the service traffic (2000 bytes / second) of this node pair for weighting, and obtains a service traffic weight value of 600. Combining the normalized values of the channel interference intensity of 20 dB and the spectrum occupancy rate of 90%, the channel comprehensive quality index of the node is calculated as 0.75 according to the ratio of 0.4:0.3:0.3.

[0091] In one embodiment, according to the channel comprehensive quality index of each node, obtain the spatial distance relationship and signal coverage intensity between nodes, and establish a dynamic channel resource allocation table including:

[0092] S121. Determine the signal transmission power and receiving sensitivity of each node based on the comprehensive channel quality index of the node, and generate the actual communication distance between nodes according to the signal strength attenuation value.

[0093] Specifically, the SDN controller first establishes a node power control table, and the table entries include: node ID, current transmission power, maximum transmission power, minimum transmission power, power adjustment step size, and historical power record. For the 4 OpenFlow switches in this embodiment, the controller sets their initial transmission power to 20 dBm respectively, limits the maximum transmission power to 26 dBm, limits the minimum transmission power to 17 dBm, and the power adjustment step size is 3 dBm. The controller reads the comprehensive channel quality index of the node every 30 seconds and dynamically adjusts the transmission power according to the index value (the comprehensive channel quality index of the node).

[0094] Specifically, the SDN controller in the present invention implements a set of adaptive power adjustment mechanism. Generating the actual communication distance between nodes according to the signal strength attenuation value includes: when the comprehensive channel quality index of the node is higher than the first threshold, reducing the transmission power to the minimum power limit; when the comprehensive channel quality index of the node is between the first threshold and the second threshold, keeping the current transmission power unchanged; when the comprehensive channel quality index of the node is between the second threshold and the third threshold, increasing the transmission power by step size; when the comprehensive channel quality index of the node is lower than the third threshold, increasing the transmission power to the maximum power limit; calculating the signal strength attenuation value according to the difference between the signal strength measured by the receiving node and the transmission power of the sending node; determining the transmission distance corresponding to when the received signal strength is equal to the receiving sensitivity threshold as the actual communication distance between nodes; where the controller uniformly sets the receiving sensitivity for all nodes, and the first threshold, the second threshold, and the third threshold are used for hierarchical adjustment of the transmission power based on the comprehensive channel quality index; the receiving sensitivity is used to determine the maximum effective communication distance between nodes.

[0095] Specifically, in the above embodiment, based on the comprehensive channel quality index 0.75 obtained in S113, since this value is between the first threshold 0.8 and the second threshold 0.7, the controller keeps the transmission power of node 1 unchanged at 20 dBm; since the comprehensive channel quality index of node 2 is 0.65, which is between the second threshold 0.7 and the third threshold 0.4, the controller increases its transmission power from 20 dBm to 23 dBm by step size; the comprehensive channel quality index of node 3 is 0.35, which is lower than the third threshold 0.4, so the controller increases its transmission power to the maximum power limit of 26 dBm; the comprehensive channel quality index of node 4 is 0.82, which is higher than the first threshold 0.8, so the controller reduces its transmission power to the minimum power limit of 17 dBm. At the same time, the controller uniformly sets the receiving sensitivity of each node to -85 dBm as the reference value for judging the effective communication distance.

[0096] Specifically, the SDN controller creates a signal strength monitoring table, and the table entries include: the sending node ID, the receiving node ID, the transmission power, the received signal strength, the signal attenuation value, the measurement timestamp, and the link status. During the monitoring period from 10:00:30 to 10:00:40, the controller collects the signal strength data between each pair of nodes through the port statistics function of the OpenFlow switch. For the pair of nodes (node 1 and node 2) marked as stable traffic in S113, when node 1 sends a signal with a power of 20 dBm, the received signal strength measured by node 2 is -65 dBm. The controller calculates the signal attenuation value to be 85 dB and records this data in the monitoring table.

[0097] Specifically, in the above embodiment, the SDN controller generates a 4×4 actual communication distance matrix based on the accumulated signal strength data. Among them, the actual communication distance between node 1 and node 2 (i.e., the link with a traffic volume of 2000 bytes / second in S113) is 120 meters, and the signal quality is stable; the actual communication distance between node 2 and node 3 is 180 meters, but affected by a 90% spectrum occupancy rate, the signal quality fluctuates greatly; the actual communication distance between node 3 and node 4 is 150 meters, and it is significantly affected by 20 dB channel interference; the distance between node 1 and node 4 reaches 200 meters and is already at the coverage edge. The controller stores these distance relationships and link quality information in the network topology database for subsequent signal coverage area division.

[0098] S122. Divide the signal overlapping coverage area and the weak coverage area according to the actual communication distance between nodes, and determine the available channel numbers for each area based on the signal interference degree;

[0099] Specifically, the SDN controller first creates a coverage area division table, and the table entries include: area ID, area type, covered node list, area range coordinates, signal strength distribution, and area status flag. In the present invention, the controller models the signal coverage range of each node as a circular area with the node as the center and the actual communication distance as the radius based on the actual communication distance matrix R generated in S121. For node i, the radius r of its coverage circle i takes the maximum value of the communication distances between this node and other nodes.

[0100] Specifically, in the above embodiment, the SDN controller generates a 4×4 actual communication distance matrix R (unit: meter) based on the accumulated signal strength data:

[0101] R = [0, 120, 160, 200;

[0102] 120, 0, 180, 190;

[0103] 160,180,0,150;

[0104] 200,190,150,0];

[0105] Calculated according to matrix R: The coverage radius r1 of node 1 is 200 meters (the maximum distance from node 4), the coverage radius r2 of node 2 is 190 meters (the maximum distance from node 4), the coverage radius r3 of node 3 is 180 meters (the maximum distance from node 2), and the coverage radius r4 of node 4 is 200 meters (the maximum distance from node 1). Among them, the actual communication distance between node 1 and node 2 (i.e., the link with a traffic volume of 2000 bytes / second in S113) is 120 meters, and the signal quality is stable; the actual communication distance between node 2 and node 3 is 180 meters, but affected by a 90% spectrum occupancy rate, the signal quality fluctuates greatly; the actual communication distance between node 3 and node 4 is 150 meters, and it is significantly affected by 20dB channel interference; the distance between node 1 and node 4 reaches 200 meters and is already at the coverage edge. The controller stores these distance relationships and link quality information in the network topology database for subsequent signal coverage area division.

[0106] Specifically, in this embodiment, the 200-meter coverage radius of node 1 overlaps with the 190-meter coverage radius of node 2, and the overlapping area accounts for 45% of the coverage area of node 1, exceeding the preset threshold of 30%. Therefore, this area is marked as the overlapping coverage area RC1; the signal strength in the intersection area of the 180-meter coverage radius of node 3 and the 200-meter coverage radius of node 4 is lower than -75dBm, and this area is marked as the weak coverage area WC1.

[0107] Specifically, the SDN controller creates a signal interference monitoring table, and the table entries include: area ID, number of interference sources, power of each interference source, cumulative interference value, and interference level. During the monitoring period from 10:00:40 to 10:00:50, the controller detects that there are 2 interference sources in the overlapping coverage area RC1, with signal powers of 2mW and 1mW respectively, spectrum overlapping factors of 0.8 and 0.6 respectively, and a cumulative interference value of 2.8mW; 1 interference source is detected in the weak coverage area WC1, with a signal power of 0.5mW, a spectrum overlapping factor of 0.4, and a cumulative interference value of 0.2mW.

[0108] Specifically, when it is detected that the cumulative interference value of the overlapping coverage area RC1 is 2.8mW, which is at a medium interference level (1mW to 5mW), the controller allocates 2 available channels {channel 1, channel 6} for this area; when it is detected that the cumulative interference value of the weak coverage area WC1 is 0.2mW, which belongs to a low interference level (less than 1mW), but due to its weak coverage characteristics, the controller allocates 2 available channels {channel 11, channel 13} for this area.

[0109] Specifically, in this embodiment, the SDN controller stores the area division and channel allocation results in the channel resource table. The table entries include: area type, area range, covered nodes, signal strength, interference level, and available channel list. The record of the overlapping coverage area RC1 is {type = overlapping coverage area, range = (200 meters, 190 meters), nodes = (1, 2), signal strength = -65 dBm, interference level = medium, available channels = (1, 6)}; the record of the weak coverage area WC1 is {type = weak coverage area, range = (180 meters, 200 meters), nodes = (3, 4), signal strength = -78 dBm, interference level = low, available channels = (11, 13)}.

[0110] S123. Based on the number of available channels in each area, count the spectrum resource occupancy of the currently accessed terminals, and establish a dynamic channel resource allocation table according to the bursty characteristics of the service traffic;

[0111] Specifically, the SDN controller first establishes a terminal access statistics table. The table entries include: terminal MAC address, affiliated area, main node ID, access time, service type, and resource requirements. During the statistical period from 10:00:50 to 10:01:00, the controller detects that 3 terminals {MAC1, MAC2, MAC3} have accessed the overlapping coverage area RC1, which are respectively managed by nodes 1 and 2, and the occupied bandwidths are 5 MHz, 3 MHz, and 4 MHz respectively; 2 terminals {MAC4, MAC5} have accessed the weak coverage area WC1, both of which are in the roaming state, and the occupied bandwidths are 2 MHz and 3 MHz respectively.

[0112] Specifically, the SDN controller creates a service characteristic analysis table. The table entries include: terminal ID, service type, average traffic, peak traffic, burst coefficient, and priority flag. The controller records for the terminal MAC1 in the overlapping coverage area RC1 that: the average value of its service traffic within 10 seconds is 8 Mbps, the peak value reaches 12 Mbps, and the calculated burst coefficient is 0.5; the burst coefficients of the terminals MAC2 and MAC3 are 0.3 and 0.4 respectively. The burst coefficients of the terminals MAC4 and MAC5 in the weak coverage area WC1 are 0.2 and 0.3 respectively.

[0113] Specifically, the SDN controller implements a set of resource reservation mechanisms. When detecting that the burst coefficient of the terminal MAC1 is 0.5, the controller reserves 25% of the bandwidth on channel 1; the burst coefficients of the terminals MAC2 and MAC3 are relatively low, and a total of 15% of the bandwidth is reserved on channel 6; due to the relatively low burst coefficient and the roaming state of the terminals in the weak coverage area WC1, 10% of the bandwidth is reserved on channels 11 and 13 respectively.

[0114] Specifically, in this embodiment, the SDN controller generates a channel resource dynamic allocation table, and the table items include: channel ID, region, current terminal list, resource occupancy, reserved bandwidth ratio and adjustment timestamp. The record of channel 1 is {channel = 1, region = RC1, terminal = MAC1, occupancy = 25%, reservation = 25%, time = 10:01:00}; the record of channel 6 is {channel = 6, region = RC1, terminal = (MAC2, MAC3), occupancy = 35%, reservation = 15%, time = 10:01:00}; the records of channels 11 and 13 are {channel = 11 / 13, region = WC1, terminal = (MAC4 / MAC5), occupancy = 20% / 15%, reservation = 10% / 10%, time = 10:01:00} respectively.

[0115] In one embodiment, based on the channel resource dynamic allocation table, optimizing channel allocation through a channel switching solution and generating a multi-dimensional resource view include:

[0116] S131. Calculate the spectrum utilization efficiency in each area according to the channel resource dynamic allocation table, identify the spectrum resource limited area, and generate a frequency occupancy distribution map in combination with the matching degree of channel quality and service requirements;

[0117] Specifically, the frequency occupancy distribution map generated by the SDN controller adopts a two-dimensional coordinate format, with the horizontal axis being the channel number (1-13) and the vertical axis being the occupancy rate (0% to 100%). The solid-line box in the figure marks the channel usage of RC1: Channel 1 and Channel 6 each display an occupancy bar, where the height of the occupancy bar of Channel 1 is close to the top, indicating a congested state, and Channel 6 displays two superimposed occupancy bars, indicating dual-terminal sharing; the dotted-line box marks the channel usage of WC1: Channel 11 and Channel 13 each display an occupancy bar. The information and spectrum efficiency value of the corresponding terminal MAC1-MAC5 are marked with text above each occupancy bar.

[0118] S132. Determine the possibility of channel reuse based on the distribution of spectrum resource-restricted areas, formulate a channel switching plan based on the interference level between channels, and form a spatial coverage blind area map based on the spatial distance relationship between nodes and signal coverage strength;

[0119] Specifically, the spatial coverage blind spot map generated by the controller adopts a plane grid format, with the coordinate grid divided into units of 10 meters. The four node positions are marked with black dots in the figure, the signal coverage range of each node is represented by concentric circles, and the circle density represents the signal strength. RC1 is displayed as the overlapping part of the two coverage circles, filled with oblique lines; WC1 is displayed as the intersection of the two coverage circles, filled with dots. Blind spot B1 is displayed as the blank area between nodes 2 and 3, and blind spot B2 is displayed as the blank area at the edge of the coverage of nodes 1 and 4, and is marked with a dotted box with the specific signal strength value marked inside.

[0120] S133. When channel congestion occurs, adjust the available channel allocation for each area through a channel switching scheme, and construct a service traffic priority distribution map based on the adjusted service traffic distribution.

[0121] Specifically, the service traffic priority distribution map generated by the controller adopts a concentric circle form. The outer circle is divided into two semi-circles, RC1 and WC1, by a thick solid line. The middle circle is segmented by different line types (solid line / dashed line / dotted line) according to three priorities, P1 / P2 / P3. The inner circle is divided by sectors to show the traffic proportion of each terminal MAC1 - MAC5. The current channel number and bandwidth reservation value are marked with text in each sector. An arrow in the figure indicates the switching path of MAC1 from channel 1 to channel 3, and the priority change is marked.

[0122] Specifically, in this embodiment, the specific data of the multi-dimensional resource view generated by the controller are as follows: The frequency occupancy distribution map shows that the occupancy rates of channels {1, 3, 6} in the RC1 area are {90%, 30%, 55%} respectively, and the occupancy rates of channels {9, 13} in the WC1 area are {25%, 15%}; The spatial coverage blind area map marks two blind areas B1 (150 - 170 meters, 80 - 100 meters) and B2 (180 - 200 meters, 180 - 200 meters), with signal strengths of -85 dBm and -82 dBm respectively; In the service traffic priority distribution map, the P1-level service MAC1 accounts for 40% of the total traffic, the P2-level services MAC2 / MAC3 account for 35%, and the P3-level services MAC4 / MAC5 account for 25%.

[0123] In one embodiment, according to the multi-dimensional resource view, dividing the multi-level coverage domain of the wireless network, identifying the service load level of each coverage domain, and generating a pre-allocation scheme for cross-domain bandwidth resources includes:

[0124] S21. Based on the frequency occupancy distribution map and the spatial coverage blind area map in the multi-dimensional resource view, divide the wireless network into a core coverage domain, an edge coverage domain, and a relay coverage domain, and establish a real-time shared channel for the resource status between domains;

[0125] Specifically, the wireless network is divided into a core coverage area, an edge coverage area, and a relay coverage area, and establishing a real-time sharing channel for the resource status between domains includes: obtaining the spectrum resource index of each area in the frequency occupancy distribution map based on the product of the channel occupancy rate and the number of available channels within the area; obtaining the coverage quality index of each area in the spatial coverage blind area map based on the product of the average signal strength and the ratio of the non-blind area within the area; mapping the spectrum resource index and the coverage quality index of the area to be divided to a two-dimensional evaluation matrix, determining the coverage area type of the area to be divided based on the quadrant distribution in the two-dimensional evaluation matrix, and establishing a regular sharing channel for the resource status between domains; where the horizontal axis of the two-dimensional evaluation matrix represents the spectrum resource index, and the vertical axis of the two-dimensional evaluation matrix represents the coverage quality index.

[0126] Specifically, determining the coverage area type of the area to be divided based on the quadrant distribution in the two-dimensional evaluation matrix and establishing a regular sharing channel for the resource status between domains includes: when the area to be divided is in the first quadrant, it is divided into a core coverage area, and the total amount of allocable resources is broadcast to other domains regularly; when the area to be divided is in the third quadrant, it is divided into an edge coverage area, and the resource demand and service priority are reported to the relay coverage area regularly; when the area to be divided is in the second or fourth quadrant, it is divided into a relay coverage area, and the resource status mapping table between domains is updated regularly and resource allocation is coordinated.

[0127] Specifically, the controller performs area division based on the frequency occupancy distribution map and the spatial coverage blind area map in S133: for the RC1 area, the spectrum resource index is calculated as the product of the channel occupancy rates {0.9, 0.3, 0.55} and the number of available channels 3, which is 0.45, and the coverage quality index is calculated as the product of the average signal strength -65 dBm and the ratio of the non-blind area 1, which is 0.85, mapped to the fourth quadrant of the evaluation matrix and divided into the relay coverage area TD1; for the WC1 area, the spectrum resource index is calculated as the product of the channel occupancy rates {0.25, 0.15} and the number of available channels 2, which is 0.08, and the coverage quality index is calculated as the product of the average signal strength -78 dBm and the ratio of the non-blind area 0.6, which is 0.25, mapped to the third quadrant of the evaluation matrix and divided into the edge coverage area ED1. TD1 updates the resource status mapping table between domains every 100 ms, and ED1 reports the resource demand to TD1 every 100 ms.

[0128] S22. Generate a resource pool containing the total available bandwidth of each coverage area based on the cross-domain resource data obtained from the resource status sharing channel between domains, and identify the service load levels of each coverage area through the service traffic priority distribution map;

[0129] Specifically, the controller regularly obtains the resource data of each coverage area through the inter-domain resource status sharing channel. For the core coverage area, it calculates the total bandwidth sum of all available channels; for the edge coverage area, it calculates the total bandwidth sum of the channels used independently; for the relay coverage area, it calculates the total bandwidth sum of the channels that can be reused. At the same time, the controller analyzes the service traffic priority distribution map, identifies the quantity distribution and bandwidth occupancy of different priority services within each coverage area, and generates the service load status table for each area.

[0130] S23. Calculate the bandwidth demand and allocable amount of each coverage area based on the service load level of each coverage area, and determine the pre-allocation scheme of cross-domain bandwidth resources.

[0131] Specifically, the controller performs bandwidth demand analysis according to the service load status table of each coverage area. For the core coverage area, it gives priority to ensuring the bandwidth demand of P1-level services, and the remaining bandwidth is allocated to P2-level services proportionally; for the edge coverage area, it reserves part of the bandwidth for P3-level roaming services, and the remaining bandwidth can be used for local services; for the relay coverage area, on the basis of meeting the local service requirements, it reserves part of the bandwidth for inter-domain service forwarding.

[0132] Specifically, determining the pre-allocation scheme of cross-domain bandwidth resources includes: first calculating the bandwidth surplus of each coverage area, that is, the total available bandwidth minus the currently occupied bandwidth by services; then setting the pre-allocation priority based on the bandwidth surplus, and the coverage area with a higher surplus has a higher resource allocation weight; then setting the bandwidth reservation threshold for each coverage area, and when the bandwidth demand of a certain area exceeds the reservation threshold, it can apply for bandwidth resources from a high-priority area; finally, formulating the bandwidth borrowing and return strategy to ensure that cross-domain resources can be recycled and reallocated in a timely manner.

[0133] Specifically, in this embodiment, the controller divides the coverage area based on the two-dimensional evaluation matrix: the spectrum resource index of 0.45 and the coverage quality index of 0.85 in the RC1 area are mapped to the fourth quadrant and divided into the relay coverage area TD1; the spectrum resource index of 0.076 and the coverage quality index of 0.25 in the WC1 area are mapped to the third quadrant and divided into the edge coverage area ED1. The inter-domain resource status is updated every 100 ms, and the latest update shows that the bandwidth demand of TD1 is 45 MHz and the allocable amount is 24 MHz, and the bandwidth demand of ED1 is 20 MHz and the allocable amount is 25 MHz. Based on the pre-allocation scheme, TD1 reserves 60% of the bandwidth for local service forwarding, and ED1 reserves 40% of the bandwidth for roaming service access.

[0134] In one embodiment, using the northbound interface of the SDN controller, execute the pre-allocation scheme of cross-domain bandwidth resources, and adjusting the bandwidth allocation parameters of each coverage area includes:

[0135] S31. Based on the pre-allocation scheme of cross-domain bandwidth resources, use the northbound interface of the SDN controller to generate a bandwidth scheduling instruction set covering inter-domains, and through the instruction parser, convert the scheduling instructions into specific bandwidth allocation parameters;

[0136] Specifically, the controller generates a bandwidth scheduling instruction set according to the pre-allocation scheme: for the core coverage domain, generate bandwidth reservation instructions and local service priority instructions; for the edge coverage domain, generate roaming service bandwidth request instructions and resource borrowing instructions; for the relay coverage domain, generate bandwidth forwarding instructions and resource coordination instructions. The instruction parser converts these scheduling instructions into specific bandwidth allocation parameters, including the bandwidth reservation ratio of each domain, the resource borrowing threshold, and the service priority weight.

[0137] S32. According to the bandwidth allocation parameters, use the dynamic bandwidth adjuster to adjust the bandwidth allocation ratio of the core coverage domain, the edge coverage domain, and the relay coverage domain in real time, and through the resource locking mechanism, ensure the stability of the bandwidth resource allocation;

[0138] It should be noted that the instruction parser is a basic component in the SDN network for converting control instructions into specific network configuration parameters, the dynamic bandwidth adjuster is the core functional module for realizing the dynamic adjustment of network resources, and the SDN controller is the core device for realizing network centralized control. This is prior art and will not be elaborated here.

[0139] Specifically, the dynamic bandwidth adjuster performs bandwidth adjustment according to the allocation parameters: when the high-priority services in the core coverage domain increase, automatically increase its bandwidth reservation ratio; when the edge coverage domain requests additional bandwidth, temporarily borrow resources from the relay coverage domain; when the relay coverage domain is overloaded, trigger the bandwidth rebalancing mechanism. The resource locking mechanism avoids frequent bandwidth adjustments by setting the minimum guaranteed bandwidth and borrowing duration limit.

[0140] Specifically, in this embodiment, the controller generates scheduling instructions based on the pre-allocation scheme: configure a bandwidth reservation instruction {reservation ratio: 60%, borrowing threshold: 80%} for TD1, and configure a bandwidth request instruction {reservation ratio: 40%, borrowing limit: 20MHz} for ED1. The dynamic bandwidth adjuster performs the adjustment: when the MAC3 bandwidth demand of the P2-level service in TD1 increases to 15MHz, temporarily borrow 10MHz bandwidth from ED1; when the total MAC4 / MAC5 bandwidth demand of the P3-level service in ED1 reaches 25MHz, apply for 5MHz additional bandwidth from TD1. Through this dynamic scheduling and allocation mechanism, the efficient utilization of network bandwidth resources is achieved.

[0141] To facilitate the understanding of the above technical solutions of the present invention, the following takes the library wireless network optimization case in a smart campus transformation project of a certain university as an example for specific description as follows:

[0142] In this project, three access points AP1 - AP3 are deployed in the reading area on the first floor of the library, mainly providing wireless access services for five mobile terminals MAC1 - MAC5. Among them, MAC1 and MAC2 are teaching terminals in the teacher's lesson preparation area, MAC3 is the working terminal of the librarian, and MAC4 and MAC5 are Internet access terminals in the student self - study area.

[0143] In the actual deployment process, we first start collecting network status data based on the south - bound interface of the SDN controller. Through the statistics of the first - level flow table, it is found that teacher terminals MAC1 - MAC3 are mainly concentrated within the coverage range of AP1, student terminals MAC4 - MAC5 mainly access through AP2, and AP3 at the corridor position is temporarily idle. Subsequently, the detection data of the second - level flow table shows that the channel interference intensities of AP1, AP2, and AP3 reach - 85dBm, - 92dBm, and - 78dBm respectively, and the corresponding spectrum occupancy rates are 90%, 25%, and 55% respectively. At the same time, the marking results of the third - level flow table indicate that teacher terminals MAC1 - MAC2 belong to P1 - level high - priority services, the library management terminal MAC3 is a P2 - level ordinary service, and student terminals MAC4 - MAC5 are marked as P3 - level low - priority services.

[0144] After obtaining these basic data, the present invention calculates the comprehensive channel quality indicators of each node: 0.72 for AP1, 0.45 for AP2, and 0.63 for AP3. Based on these indicator values, we make corresponding adjustments to the transmission power: since the indicator of AP1 is lower than the first threshold of 0.8, its power is reduced to 18dBm; the indicator of AP2 is between the second threshold of 0.4 and the third threshold of 0.6, and it needs to be increased to 22dBm in 2dB steps; while AP3 remains unchanged at 20dBm. By actually measuring the received signal strength, we finally determine that the actual communication distances of AP1 - AP2, AP2 - AP3, and AP1 - AP3 are 80m, 60m, and 100m respectively.

[0145] Next, the analysis of the multi - dimensional resource view allows us to clearly see that: within the teacher's reading area (RC1 area) centered on AP1, there are 3 available channels, and their spectrum utilization efficiencies are 0.9, 0.3, and 0.55 respectively; while in the student self - study area (WC1 area) centered on AP2, there are 2 available channels, and the spectrum utilization efficiencies are 0.25 and 0.15 respectively. Through the analysis of the two - dimensional evaluation matrix, we divide the RC1 area into the relay coverage domain TD1, and at the same time divide the WC1 area into the edge coverage domain ED1.

[0146] Finally, the pre - allocation scheme for cross - domain bandwidth resources is determined as follows: 60% of the bandwidth is reserved for local services in the teacher area for TD1, and 40% of the bandwidth is reserved for roaming services in the student area for ED1. The flexibility of this allocation scheme lies in that when the library management terminal MAC3 needs to handle a large number of book borrowing and returning operations, it can temporarily borrow bandwidth resources from the student area ED1; during peak student hours after school, MAC4 and MAC5 can also apply for additional bandwidth from the teacher area TD1. Practice has proved that this dynamic adjustment mechanism has well solved the bandwidth demand problems in different areas of the library at different times and significantly improved the user experience.

[0147] As Figure 2 shown, according to another embodiment of the present invention, a visualization dynamic allocation system for communication network bandwidth resources based on SDN is further provided. The visualization dynamic allocation system for communication network bandwidth resources based on SDN includes:

[0148] A resource data calculation unit 1, configured to obtain the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network based on the south - bound interface of the SDN controller, and generate a multi - dimensional resource view through a channel resource dynamic allocation table;

[0149] A coverage domain division unit 2, configured to divide the multi - level coverage domain of the wireless network according to the multi - dimensional resource view, identify the service load level of each coverage domain, and generate a pre - allocation scheme for cross - domain bandwidth resources;

[0150] A bandwidth scheduling execution unit 3, configured to execute the pre - allocation scheme for cross - domain bandwidth resources by using the north - bound interface of the SDN controller and adjust the bandwidth allocation parameters of each coverage domain.

[0151] In summary, by means of the above technical solutions of the present invention, network status data is obtained through the southbound interface and a multi-dimensional resource view is generated. Based on the resource view, multi-level coverage domain division and bandwidth pre-allocation of the network are realized. Finally, dynamic scheduling and allocation are performed through the northbound interface. The overall solution realizes visual monitoring, precise division, and flexible scheduling of the network resource status, significantly improving the utilization efficiency of network bandwidth resources. The present invention uses a multi-level flow table mechanism to obtain network node data through the southbound interface of the SDN controller. The first-level flow table establishes an initial traffic matrix, the second-level flow table obtains the channel interference intensity and spectrum occupancy rate, and the third-level flow table marks the priority of service traffic. A multi-dimensional resource view including a frequency occupancy distribution map, a spatial coverage blind area map, and a service traffic priority distribution map is generated based on the channel resource dynamic allocation table, realizing all-round visual monitoring of the wireless network resource status and overcoming the technical problem of incomplete perception of network resource status in the prior art. The present invention maps the spectrum resource index and the coverage quality index to a two-dimensional evaluation matrix, realizes multi-level coverage domain division of the wireless network based on the quadrant distribution, and establishes a real-time sharing channel for the resource status between domains, enabling the core coverage domain to regularly broadcast the total amount of allocable resources, the edge coverage domain to regularly report resource requirements, and the relay coverage domain to regularly update the resource status mapping table, so that the division of network resources is more accurate and reasonable. At the same time, through the pre-allocation scheme of cross-domain bandwidth resources, the utilization efficiency of network resources is improved. The present invention performs dynamic scheduling and allocation of bandwidth resources through the northbound interface of the SDN controller, generates a bandwidth scheduling instruction set based on the pre-allocation scheme and converts it into specific allocation parameters, uses a dynamic bandwidth adjuster to adjust the bandwidth allocation ratio of each coverage domain in real time, increases the reservation ratio when the business in the core coverage domain increases, can borrow relay domain resources when needed in the edge coverage domain, and ensures allocation stability through a resource locking mechanism, solving the technical defect of fixed network resource allocation and difficult dynamic adjustment in the prior art.

[0152] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for visual dynamic allocation of communication network bandwidth resources based on SDN, characterized in that Including: S1. Based on the southbound interface of the SDN controller, obtain the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network, and generate a multi-dimensional resource view through the channel resource dynamic allocation table; S2. According to the multi-dimensional resource view, divide the multi-level coverage areas of the wireless network, identify the service load levels of each coverage area, and generate a pre-allocation plan for cross-domain bandwidth resources; S3. Use the northbound interface of the SDN controller to execute the pre-allocation plan for cross-domain bandwidth resources and adjust the bandwidth allocation parameters of each coverage area.

2. The method for visual dynamic allocation of communication network bandwidth resources based on SDN according to claim 1, wherein The southbound interface based on the SDN controller, obtaining the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network, and generating a multi-dimensional resource view through the channel resource dynamic allocation table includes: S11. Based on the southbound interface of the SDN controller, through the multi-level flow table mechanism of the network switch, obtain the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network in a combined active and passive manner, and generate the channel comprehensive quality index of the node; S12. According to the channel comprehensive quality index of each node, obtain the spatial distance relationship and signal coverage intensity between nodes, and establish a channel resource dynamic allocation table; S13. Based on the channel resource dynamic allocation table, optimize the channel allocation through the channel switching scheme and generate a multi-dimensional resource view.

3. The method for visual dynamic allocation of communication network bandwidth resources based on SDN according to claim 2, wherein The southbound interface based on the SDN controller, obtaining the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network in a combined active and passive manner through the multi-level flow table mechanism of the network switch, and generating the channel comprehensive quality index of the node includes: S111. The southbound interface based on the SDN controller establishes a connection with the network switch, configures the first-level flow table to receive the packet statistical information reported by the switch, and establishes an initial traffic matrix between nodes through the passive listening mechanism; S112. According to the initial traffic matrix, configure the second-level flow table for active probe packet injection, obtain the channel interference intensity and spectrum occupancy rate, and generate the real-time traffic change trend through the differential calculation technology; S113. Based on the real-time traffic change trend, configure the third-level flow table for service traffic priority marking, perform hierarchical weighted calculation on the service traffic data, and output the channel comprehensive quality index of the node.

4. The method for visual dynamic allocation of communication network bandwidth resources based on SDN according to claim 2, wherein The obtaining the spatial distance relationship and signal coverage intensity between nodes according to the channel comprehensive quality index of each node and establishing a channel resource dynamic allocation table includes: S121. Based on the channel comprehensive quality index of the node, determine the signal transmission power and receiving sensitivity of each node, and generate the actual communication distance between nodes according to the signal strength attenuation value; S122. According to the actual communication distance between nodes, divide the signal overlapping coverage area and weak coverage area, and determine the available channel number of each area based on the signal interference degree; S123. Based on the available channel number of each area, count the spectrum resource occupancy of the currently accessed terminals, and establish a channel resource dynamic allocation table according to the bursty characteristics of the service traffic.

5. The method for visual dynamic allocation of communication network bandwidth resources based on SDN according to claim 4, wherein Generating the actual communication distance between nodes according to the signal strength attenuation value includes: When the channel comprehensive quality index of a node is higher than the first threshold, reducing the transmission power to the minimum power limit; When the channel comprehensive quality index of a node is between the first threshold and the second threshold, keeping the current transmission power unchanged; When the channel comprehensive quality index of a node is between the second threshold and the third threshold, increasing the transmission power in steps; When the channel comprehensive quality index of a node is lower than the third threshold, boosting the transmission power to the maximum power limit; Calculating the signal strength attenuation value based on the difference between the signal strength measured by the receiving node and the transmission power of the sending node; Determining the transmission distance corresponding to when the received signal strength equals the receive sensitivity as the actual communication distance between nodes.

6. The method for visual dynamic allocation of communication network bandwidth resources based on SDN according to claim 2, wherein Optimizing channel allocation through a channel switching scheme based on the channel resource dynamic allocation table and generating a multi-dimensional resource view includes: S131. According to the channel resource dynamic allocation table, calculating the spectrum utilization efficiency in each area, identifying the spectrum resource limited areas, and generating a frequency occupancy distribution map in combination with the matching degree of channel quality and service requirements; S132. Based on the distribution of the spectrum resource limited areas, determining the possibility of channel multiplexing, formulating a channel switching scheme according to the inter-channel interference level, and at the same time forming a spatial coverage blind area map in combination with the spatial distance relationship and signal coverage intensity between nodes; S133. When channel congestion occurs, adjusting the available channel allocation in each area through the channel switching scheme and constructing a service traffic priority distribution map based on the adjusted service traffic distribution; Among them, the multi-dimensional resource view includes a frequency occupancy distribution map, a spatial coverage blind area map, and a service traffic priority distribution map.

7. The method for visual dynamic allocation of communication network bandwidth resources based on SDN according to claim 1, characterized in that, Dividing the multi-level coverage area of the wireless network according to the multi-dimensional resource view, identifying the service load level of each coverage area, and generating a pre-allocation scheme for cross-domain bandwidth resources includes: S21. Based on the frequency occupancy distribution map and the spatial coverage blind area map in the multi-dimensional resource view, dividing the wireless network into a core coverage area, an edge coverage area, and a relay coverage area, and establishing a real-time sharing channel for inter-domain resource status; S22. Generating a resource pool containing the total available bandwidth of each coverage area according to the cross-domain resource data obtained through the inter-domain resource status sharing channel, and identifying the service load level of each coverage area through the service traffic priority distribution map; S23. Based on the service load level of each coverage area, calculating the bandwidth demand and allocable amount of each coverage area, and determining the pre-allocation scheme for cross-domain bandwidth resources.

8. The method for visual dynamic allocation of communication network bandwidth resources based on SDN according to claim 7, characterized in that, Dividing the wireless network into a core coverage area, an edge coverage area, and a relay coverage area and establishing a real-time sharing channel for inter-domain resource status includes: Based on the product of the channel occupancy rate and the number of available channels in the area, determining the spectrum resource index of each area in the frequency occupancy distribution map; Obtaining the coverage quality index of each area in the spatial coverage blind area map according to the product of the average signal strength in the area and the non-blind area area ratio; Mapping the spectrum resource index and the coverage quality index of the area to be divided to a two-dimensional evaluation matrix, determining the coverage area type of the area to be divided based on the quadrant distribution in the two-dimensional evaluation matrix, and establishing a regular sharing channel for inter-domain resource status; Among them, the horizontal axis of the two-dimensional evaluation matrix represents the spectrum resource index, and the vertical axis of the two-dimensional evaluation matrix represents the coverage quality index.

9. The method for visual dynamic allocation of communication network bandwidth resources based on SDN according to claim 8, wherein Determining the coverage domain type of the area to be divided based on the quadrant distribution in the two-dimensional evaluation matrix and establishing a regular sharing channel for the resource status between domains includes: When the area to be divided is located in the first quadrant, it is divided into a core coverage domain, and the total amount of allocable resources is broadcast to other domains regularly; When the area to be divided is located in the third quadrant, it is divided into an edge coverage domain, and the resource demand and service priority are reported to the relay coverage domain regularly; When the area to be divided is located in the second or fourth quadrant, it is divided into a relay coverage domain, and the resource status mapping table between domains is updated regularly and resource allocation is coordinated.

10. A visualization dynamic allocation system for communication network bandwidth resources based on SDN, which is used to implement the visualization dynamic allocation method for communication network bandwidth resources based on SDN described in any one of claims 1-9, characterized in that, The system includes: A resource data calculation unit, configured to obtain the channel interference intensity, spectrum occupancy rate, and service traffic priority data of each node in the wireless network based on the southbound interface of the SDN controller, and generate a multi-dimensional resource view through the channel resource dynamic allocation table; A coverage domain division unit, configured to divide the multi-level coverage domains of the wireless network according to the multi-dimensional resource view, identify the service load levels of each coverage domain, and generate a pre-allocation scheme for cross-domain bandwidth resources; A bandwidth scheduling execution unit, configured to execute the pre-allocation scheme for cross-domain bandwidth resources by using the northbound interface of the SDN controller and adjust the bandwidth allocation parameters of each coverage domain.

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