CN115226138A - CoAP-oriented efficient data collection method for Internet of things - Google Patents
CoAP-oriented efficient data collection method for Internet of things Download PDFInfo
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- 238000013480 data collection Methods 0.000 title claims abstract description 23
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- 238000004891 communication Methods 0.000 claims abstract description 15
- 238000007906 compression Methods 0.000 claims description 16
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- 238000005265 energy consumption Methods 0.000 description 8
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- H—ELECTRICITY
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- H04W24/04—Arrangements for maintaining operational condition
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W28/00—Network traffic management; Network resource management
- H04W28/02—Traffic management, e.g. flow control or congestion control
- H04W28/06—Optimizing the usage of the radio link, e.g. header compression, information sizing, discarding information
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W28/00—Network traffic management; Network resource management
- H04W28/02—Traffic management, e.g. flow control or congestion control
- H04W28/08—Load balancing or load distribution
- H04W28/09—Management thereof
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W28/00—Network traffic management; Network resource management
- H04W28/02—Traffic management, e.g. flow control or congestion control
- H04W28/08—Load balancing or load distribution
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- H04W28/0933—Management thereof using policies based on load-splitting ratios
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- H—ELECTRICITY
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- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W28/00—Network traffic management; Network resource management
- H04W28/02—Traffic management, e.g. flow control or congestion control
- H04W28/08—Load balancing or load distribution
- H04W28/09—Management thereof
- H04W28/0958—Management thereof based on metrics or performance parameters
- H04W28/0967—Quality of Service [QoS] parameters
- H04W28/0975—Quality of Service [QoS] parameters for reducing delays
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Abstract
The invention discloses a CoAP-oriented efficient data collection method for the Internet of things, which adopts NB-IoT as a low-power-consumption network communication link, adopts a CoAP application layer communication protocol at the upper layer, and comprises the following steps: step 1: filtering CoAPPDU; step 2: merging and compressing; and step 3: and (4) self-adaptive uploading. The method filters similar data of the Internet of things, reduces redundant information, solves the problems of low effective load rate and high head overhead of a lightweight network communication protocol in a traditional low-power-consumption network, adaptively adjusts a data uploading period, reduces the data transmission amount of the network, and makes a good balance between uplink data delay and equipment power consumption.
Description
Technical Field
The invention belongs to the technical field of Internet of things, relates to a data collection method of Internet of things, and particularly relates to a high-efficiency data collection method of Internet of things for CoAP.
Background
With the rapid development of the internet of things technology, various billions of light-weight resource limited terminal devices, such as sensors, electric meters and the like, exist in the real world. The equipment has higher requirements on network communication energy consumption, time delay, high data transmission efficiency and the like. The low power consumption wide area network (LPWAN) technology is widely applied to the field of internet of things due to the characteristics of low energy consumption, wide coverage, large capacity and the like, and currently, the LPWAN includes NB-IoT, eMTC and the like deployed in authorized frequency bands and LoRa, sigfox and the like deployed in unauthorized frequency bands. The NB-IoT is a low-power-consumption wireless wide area network technology based on the existing LTE specification and facility development, has the advantages of wide coverage, large connection, low power consumption, low cost and the like, and well meets the requirements of various light-weight resource-limited Internet of things terminal devices. Meanwhile, the resource-limited lightweight internet of things equipment also puts high requirements on an application layer network protocol, and the CoAP protocol oriented to the resource-limited equipment is widely applied. CoAP runs on UDP protocol, the message format is compact, and the basic functions of Internet of things data uploading, configuration issuing and the like can be met based on REST architecture design.
Because the data of the Internet of things is generally short and small and the information level is low, the problem of low data transmission effective load rate exists in the lightweight equipment of the Internet of things. Meanwhile, the LPWAN puts higher requirements on energy consumption, and the traditional low-power-consumption network communication link and the upper Internet of things application layer protocol generally have the problems of lack of data filtering and self-adaptive data uploading mechanism. Too high data collection frequency configuration causes information redundancy of the internet of things equipment, network congestion is caused, and the service life of low-power-consumption equipment is shortened. Too low frequency configuration causes the uplink delay of the device to increase sharply, and the real-time performance of data is reduced. Furthermore, the bandwidth of the LPWAN is limited, requirements are made on message load, and currently, the SenML and CBOR internet of things data compression technology is widely applied, the SenML is a simple information model for sensor data and equipment parameter transmission, and the CBOR (concise binary object display) is a binary-based data compression algorithm, but the method has a poor effect on compressing short data of the internet of things, and does not support the function of combining and compressing a plurality of data messages. Therefore, a more efficient data transmission method for the internet of things is needed.
Disclosure of Invention
The invention provides a CoAP-oriented Internet of things efficient data collection method, and aims to solve the problems that data transmission effective load rate is low due to short data of the Internet of things, and a traditional Internet of things lightweight communication protocol is lack of adaptive data collection and adaptive data uploading. The method filters similar data of the Internet of things, reduces redundant information, solves the problems of low effective load rate and high head overhead of a lightweight network communication protocol in a traditional low-power-consumption network, adaptively adjusts a data uploading period, reduces the data transmission amount of the network, and makes a good balance between uplink data delay and equipment power consumption.
The purpose of the invention is realized by the following technical scheme:
a CoAP-oriented Internet of things efficient data collection method adopts NB-IoT as a low-power-consumption network communication link, adopts a CoAP application layer communication protocol at an upper layer, and comprises the following steps:
step 1: coAP PDU filtering
Comparing the data content of the CoAP protocol data unit PDU prepared to be uploaded by the lightweight terminal equipment with the data transmitted last time, if the relative error range is less than rate% or the absolute difference value is less than diff, not further processing the data, and waiting for new data to arrive, otherwise, entering step 2;
step 2: merging compression
Step 2.1: if the time Interval from the last data transmission is larger than MAX _ Interval, the step 2.4 is carried out, otherwise, whether the number in the CoAP PDU queue exceeds MAX _ PDU _ COUNT threshold value is judged, if the number exceeds the MAX _ PDU _ COUNT threshold value, the step 2.3 is carried out, otherwise, the step 1 is carried out;
step 2.2: extracting all PDU key information in a CoAP PDU queue, such as an event unique identifier token, a data packet sequence number mid, a time stamp and the like;
step 2.3: if the time Interval from the last data transmission is less than MIN _ Interval, then entering step 1;
step 2.4: packaging all CoAPPDU key information into a single PDU to form a PDU target;
step 2.5: adopting a SenML compression algorithm to reduce the timestamp load overhead for the effective load in the PDU Merged, adopting a CBOR compression algorithm to reduce the whole load overhead, and finally forming a PDU Compressed;
and step 3: adaptive upload
Step 3.1: if the PDU Compressed arrival time is more than MAX _ Interval from the last data transmission time Interval, the MAX _ Interval is increased to two times, and if the PDU Compressed arrival time is less than MAX _ Interval from the last data transmission time Interval, the MAX _ Interval is adjusted to the initial minimum value;
step 3.2: and sending the PDU Compressed to the target server.
Compared with the prior art, the invention has the following advantages:
1. the method of the invention can greatly improve the effective load rate of low-power network transmission and reduce the overhead of a transmission layer and a link layer.
2. The method can be used for filtering similar data of the Internet of things, adaptively adjusting the data uploading period, and achieving a better balance between data delay and power consumption so as to achieve the aim of efficient data transmission.
Drawings
FIG. 1 is a flow diagram of a method for adaptive data collection based on filtering and compression;
FIG. 2 is a graph comparing the data filtering effect of an adaptive data collection method based on filtering and compression;
FIG. 3 is a graph comparing network performance for an adaptive data collection method based on filtering and compression;
FIG. 4 is a graph showing a comparison of energy consumption delay of an adaptive data collection method based on filtering and compression.
Detailed Description
The technical solutions of the present invention are further described below with reference to the drawings, but the present invention is not limited thereto, and any modifications or equivalent substitutions may be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.
The invention provides a high-efficiency Data Collection method facing to a CoAP Packet Data Unit (PDU), namely a self-Adaptive Data Collection method (FC-ADC, adaptive Data Collection on filtration and Compression) based on Filtering and Compression, wherein NB-IoT is used as a low-power-consumption network communication link, a CoAP application layer communication protocol is adopted at the upper layer, and as shown in figure 1, the method comprises the following steps:
step 1: coAP PDU filtering.
Step 1.1: and adaptively adjusting rate and diff parameters according to the specific service requirements of the Internet of things. The invention provides a specific implementation mode, when the network data traffic is expected to be reduced to the maximum extent, the rate needs to be configured to be 40%, the diff needs to be configured to be 20, when the network data traffic is expected to be reduced appropriately, the rate needs to be configured to be not lower than 20%, and the diff needs to be configured to be 100.
Step 1.2: when data on an internet of things is generated, an adaptive data collection method based on filtering and compression is called for processing.
Step 1.3: and judging whether the data needs to be uploaded according to the rate and diff parameters, if so, entering the step 2, otherwise, returning to the step 1.2.
Step 2: and (5) merging and compressing.
Step 2.1: MAX _ Interval is initialized to 10 seconds, MIN _ Interval is 1 second, and MAX _ PDU _ COUNT is 4.
Step 2.2: if the time Interval is greater than MAX _ Interval from the last data transmission step 2.5 is entered.
Step 2.3: and when the time Interval is less than MAX _ Interval from the last data transmission time, judging whether the number in the CoAP PDU queue exceeds a MAX _ PDU _ COUNT threshold value. If the threshold is exceeded, step 2.4 is entered, otherwise, the next CoAP PDU is continuously waited for.
Step 2.4: and when the time Interval from the last data transmission is less than MIN _ Interval, returning to the step 1.
Step 2.5: and extracting the data arrival time, the data content, the data packet sequence number mid and the data packet identification token information of all the PDUs in the CoAP PDU queue, and encapsulating the data arrival time, the data content, the data packet sequence number mid and the data packet identification token information into a Json text.
Step 2.6: and taking the Json content as PDU Merged load information.
Step 2.7: and adopting a SenML (RFC 8428) compression algorithm to reduce the timestamp load overhead and adopting a CBOR (RFC 8949) compression algorithm to reduce the overall load overhead for the payload in the PDU Merged, and finally forming the PDU Compressed.
And 3, step 3: and (4) self-adaptive uploading.
Step 3.1: if the PDU Compressed arrival time is greater than MAX _ Interval from the last data transmission time Interval, MAX _ Interval is increased to twice itself. If the PDU Compressed arrival time is less than MAX _ Interval from the last data transmission Interval, MAX _ Interval is adjusted to the initial minimum value.
Step 3.2: and transmitting the PDU Compressed to the target server.
Example (b):
in this embodiment, the data link layer adopts a low power consumption NB-IoT link, the transport layer adopts UDP and TCP, the application layer protocol adopts CoAP, medium traffic (10 tasks) and high traffic (30 tasks) scenes are set, three relative error values of 0.3, 0.4, and 0.6 are set, and the terminal device adopts an REFIT public data set. In the data filtering stage, the data volume is respectively reduced by 99.57% and 99.85% through the AMID algorithm and the CBOR algorithm under the configuration of three relative error values, the root mean square error of the original data is 283.3 and 93.67 respectively, and compared with the AMID filtering algorithm, the filtering algorithm has higher accuracy and smaller data volume.
In the data compression and merging and adaptive uploading stage, five sets of comparison experiments are set, as shown in fig. 3, from left to right: the method is not adopted in the CoAP/UDP medium and high flow scene, the method is not adopted in the CoAP/TCP medium and high flow scene, and the method is adopted in the CoAP/TCP high flow scene, and a comparison graph of the head overhead, the network data packet quantity, the compression rate and the uplink data delay performance is obtained. Fig. 4 depicts average data delay versus NB-IoT communications module energy consumption for different data upload periods. From the figure, we can see that the adaptive data collection algorithm based on cross-layer perception can make a good tradeoff between energy consumption and data delay, a lower data uploading period can reduce energy consumption but can cause excessive data delay, and a higher data collection frequency requires NB-IoT to be more in an RRC connected state, resulting in greater energy consumption.
The invention reduces the overhead of the network transmission head part by 70.85%, reduces the number of data packets in the network by 99.85%, and achieves the data compression rate of 40.5%. Compared with a network high-frequency data sending mode, the method can effectively increase the NB-IoT communication module by 50.8% of the equipment sleep time, and compared with a low-frequency data sending mode, the method can effectively reduce 41.1% of uplink data delay, thereby ensuring the high-efficiency transmission of the data of the Internet of things.
Claims (4)
1. A CoAP-oriented efficient data collection method for the Internet of things is characterized by comprising the following steps:
step 1: coAPPDU filtering
Comparing the data content of the CoAP protocol data unit PDU prepared to be uploaded by the lightweight terminal equipment with the data transmitted last time, if the relative error range is less than rate% or the absolute difference value is less than diff, not further processing the data, and waiting for new data to arrive, otherwise, entering step 2;
step 2: merging compression
Step 2.1: if the time Interval between the last data transmission is larger than MAX _ Interval, the step 2.4 is carried out, otherwise, whether the number in the CoAPPDU queue exceeds MAX _ PDU _ COUNT threshold value is judged, if so, the step 2.3 is carried out, otherwise, the step 1 is carried out;
step 2.2: extracting all PDU key information in a CoAPPDU queue;
step 2.3: if the time Interval from the last data transmission is less than MIN _ Interval, then entering step 1;
step 2.4: packaging all CoAPPDU key information into a single PDU to form PDUMerged;
step 2.5: reducing the timestamp load overhead of the effective load in the PDUMerged by adopting a SenML compression algorithm, and reducing the overall load overhead by adopting a CBOR compression algorithm to finally form PDUCompressed;
and step 3: adaptive upload
Step 3.1: if the PDUCompressed arrival time is more than MAX _ Interval from the last data transmission time Interval, the MAX _ Interval is increased to be twice, and if the PDUCompressed arrival time is less than MAX _ Interval from the last data transmission time Interval, the MAX _ Interval is adjusted to be an initial minimum value;
step 3.2: and sending the PDUCompressed to the target server.
2. The efficient data collection method of the internet of things facing to the CoAP of claim 1, wherein in the step 1, when it is expected to reduce the network data traffic to the maximum extent, rate is configured to be 40%, diff is configured to be 20; when it is desired to properly reduce network data traffic, rate is configured to be not less than 20% parameter and diff is configured to be 100.
3. The CoAP-oriented Internet of things efficient data collection method according to claim 1, wherein in the step 2, the PDU key information comprises one or more of an event unique identifier token, a data packet sequence number mid and a time stamp.
4. The efficient data collection method for the internet of things facing the CoAP as claimed in claim 1, wherein the method adopts NB-IoT as a low power consumption network communication link, and the CoAP application layer communication protocol is adopted in an upper layer.
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| EP4395269A1 (en) * | 2022-12-28 | 2024-07-03 | Schneider Electric Industries Sas | A method of streaming industrial telemetry data from an industrial site with congestion control and payload size optimisation |
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