Intelligent alarm information management terminal and alarm host data interaction method and system

Abstract

The invention relates to a data interaction method and system for an intelligent alarm information management terminal and an alarm host, and relates to the field of data management. Character strings in alarm information are matched with a hierarchical reference dictionary and an extended dictionary to obtain corresponding dictionary indexes; outputting a numerical identifier for the numerical data in the alarm information, and adding binary data converted according to a preset fixed-point quantization rule to form a compressed data stream; exporting a shift amount by using a transformation key, performing cyclic bit shift operation on a dictionary index in the compressed data stream to obtain an encrypted compressed data stream, and enabling the numerical identifier and the binary data not to participate in the shift operation; respectively maintaining independent round trip time RTT and retransmission timeout RTO for different service priority levels; if an alarm host acknowledgement ACK message is not received in the RTO corresponding to the current service priority level, retransmission is executed; and when an acknowledgement ACK message returned by the alarm host is received, the RTT and the RTO of the corresponding service priority level are updated.

Description

Technical Field

[0001] This application belongs to the field of communication security, and in particular relates to a method and system for data interaction between an intelligent alarm information management terminal and an alarm host. Background Technology

[0002] Intelligent alarm systems play a significant role in ensuring the security of homes, communities, factories, and financial institutions. Generally, these systems consist of numerous front-end devices such as smoke detectors, infrared sensors, and door / flockers, along with an alarm control panel and a back-end server. The front-end devices monitor the environmental status in real time and, upon detecting abnormal events such as fires or unauthorized intrusions, send signals to the alarm control panel. The alarm control panel generates alarm information and reports it to the intelligent alarm information management terminal and server via wired and wireless networks such as NB-IoT, LoRaWAN, or Wi-Fi for recording. The efficiency, security, and reliability of data interaction are crucial to the overall system performance. Alarm control panels are often resource-constrained devices, and wireless communication channel bandwidth is also limited. Furthermore, in critical locations such as banks, alarm information involves user security and privacy, and transmission over open wireless networks faces security threats such as eavesdropping, tampering, and replay attacks. The Constrained Application Protocol (CoAP), based on UDP, serves as a communication standard between IoT devices, providing lightweight acknowledgment and retransmission mechanisms to handle network packet loss. However, it does not differentiate between service priorities, employing a uniform retransmission strategy for all messages, which is unreasonable in intelligent alarm scenarios. For example, the urgency of a fire alarm is far greater than that of a low battery warning. If both experience the same transmission delay due to network congestion, it could lead to serious consequences. CoAP's retransmission timeout (RTO) calculation primarily relies on the network round-trip time (RTT), failing to effectively incorporate the real-time processing status of the alarm control panel. When the alarm control panel experiences queue backlog and response delays due to handling a large number of concurrent requests, terminals may prematurely retransmit due to their inability to perceive the alarm control panel's load. This further exacerbates the burden on the alarm control panel and network congestion, creating a vicious cycle that reduces the stability and timeliness of the entire system. Summary of the Invention

[0003] To address the issues of large data volume and security vulnerabilities in the current interaction between alarm control panels and intelligent alarm information management terminals, this invention proposes a method and system for data interaction between intelligent alarm information management terminals and alarm control panels. The method includes the following steps:

[0004] The intelligent alarm information management terminal and the alarm host are pre-set with a hierarchical reference dictionary and synchronously maintain an extended dictionary based on historical interaction data; the strings in the alarm information are matched with the hierarchical reference dictionary and the extended dictionary, and if the match is successful, the corresponding dictionary index is output; for numerical data in the alarm information, a numerical identifier is output and binary data converted according to a preset point quantization rule is appended; together they form a compressed data stream;

[0005] Based on the message sequence number and timestamp bound to the pre-shared key and the priority level of the alarm information service, a transformation key is generated; the shift amount is derived using the transformation key, and a cyclic bit shift operation is performed on the dictionary index in the compressed data stream to obtain an encrypted compressed data stream, wherein the numerical identifier and the binary data do not participate in the shift operation;

[0006] The terminal places the encrypted and compressed data stream in the payload portion of the CoAP message and sets a custom Option in the Option field of the CoAP message, which includes the service priority level and the message sequence number.

[0007] The terminal maintains independent Round-Trip Time (RTT) and Retransmission Timeout (RTO) for different service priority levels. After sending the CoAP message, if no ACK confirmation is received from the alarm host within the RTO corresponding to the current service priority level, a retransmission is performed. When an ACK confirmation message is received from the alarm host, the RTT and RTO of the corresponding service priority level are updated according to the reception time of the ACK and the alarm host queue load factor carried therein.

[0008] Optionally, the hierarchical reference dictionary includes a static core dictionary layer and a semi-static application dictionary layer; the static core dictionary layer contains fixed general terms in alarm services; the semi-static application dictionary layer contains proprietary terms that remain unchanged for a period of time under specific application scenarios.

[0009] Optionally, the preset point quantization rule is as follows: multiply the numerical data by a preset quantization factor, round it, and then convert the resulting integer into a 16-bit binary two's complement form.

[0010] Optionally, the step of generating a transformation key based on the message sequence number and timestamp bound to the pre-shared key and the alarm information service priority level specifically involves:

[0011] The pre-shared key is used as the master key of the HMAC-SHA256 hash function. The message sequence number and timestamp are concatenated to form the message as input. The calculated 256-bit hash value is the transformation key.

[0012] Optionally, the step of performing a cyclic bit shift operation on the dictionary indexes in the compressed data stream to obtain the encrypted compressed data stream specifically involves:

[0013] The value of the lowest 4 bits of the transformation key is used as the shift amount;

[0014] For each 12-bit dictionary index in the compressed data stream, a left circular bit shift specified by the shift amount is performed.

[0015] Optionally, the custom option set in the Option field of the CoAP message uses the reserved Option number 2048; the value of the custom option is a 2-byte field, where the high 2 bits are used to represent the service priority level and the low 14 bits are used to represent the message sequence number.

[0016] Optionally, updating the RTT and RTO of the corresponding service priority level based on the reception time of the ACK and the alarm host queue load factor carried therein specifically involves:

[0017] After receiving the ACK message from the alarm host, calculate the Sample Round Trip Time (SampleRTT) for this message;

[0018] According to the formula Update round-trip time deviation RTTVAR, These are the weighting coefficients;

[0019] According to the formula Update the weighted average round-trip time (SRTT);

[0020] According to the formula Update retransmission timeout RTO, where It equals the alarm host queue load factor multiplied by a preset time coefficient. , SRTT is the weighting coefficient; SRTT is the average round-trip time. The SRTT value before the update. The updated SRTT value, where RTTVAR is the round-trip time offset. The RTTVAR value before the update. The new RTTVAR value calculated this time, RTO new This is the updated retransmission timeout (RTO) value.

[0021] This invention also proposes a data interaction system between an intelligent alarm information management terminal and an alarm host, comprising:

[0022] The compression unit, intelligent alarm information management terminal, and alarm host are pre-set with a hierarchical reference dictionary and synchronously maintain an extended dictionary based on historical interaction data; the string in the alarm information is matched with the hierarchical reference dictionary and the extended dictionary, and if the match is successful, the corresponding dictionary index is output; for numerical data in the alarm information, a numerical identifier is output and binary data converted according to a preset point quantization rule is appended; together they form a compressed data stream;

[0023] The encryption unit generates a transformation key based on the message sequence number and timestamp bound to the pre-shared key and the priority level of the alarm information service; it uses the transformation key to derive the shift amount and performs a cyclic bit shift operation on the dictionary index in the compressed data stream to obtain an encrypted compressed data stream, wherein the numerical identifier and the binary data do not participate in the shift operation;

[0024] The data packet generation unit, wherein the terminal places the encrypted and compressed data stream in the payload portion of the CoAP message, and sets a custom Option containing the service priority level and message sequence number in the Option field of the CoAP message;

[0025] The transmission unit, wherein the terminal maintains independent round-trip time (RTT) and retransmission timeout (RTO) for different service priority levels; after sending the CoAP message, if no ACK confirmation is received from the alarm host within the RTO corresponding to the current service priority level, a retransmission is performed; when an ACK confirmation message is received from the alarm host, the RTT and RTO of the corresponding service priority level are updated according to the reception time of the ACK and the alarm host queue load factor carried therein.

[0026] This invention achieves alarm information compression and significantly reduces the amount of transmitted data by using a combination of hierarchical base dictionary and extended dictionary for string indexing and fixed-point quantization for numerical data. Simultaneously, a lightweight encryption method is constructed by cyclically shifting the dictionary index using a key generated based on a pre-shared key, message sequence number, and timestamp. This ensures the confidentiality of alarm information without significantly increasing the terminal's computational burden. Furthermore, by setting independent retransmission timeouts for messages with different service priorities and incorporating the alarm host's queue load into the timeout calculation, it ensures that high-priority alarms receive more timely transmission guarantees, avoiding invalid retransmissions caused by the alarm host being overloaded. Attached Figure Description

[0027] Figure 1 This is a flowchart of a specific embodiment one;

[0028] Figure 2 A schematic diagram of the hierarchical base dictionary and extended dictionary;

[0029] Figure 3 A schematic diagram of the encoding;

[0030] Figure 4 This is a schematic diagram of the CoAP message structure. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0032] The term "multiple" in this application refers to two or more. Furthermore, it should be understood that the terms "first," "second," etc., used in the description of this application are used only for descriptive purposes and should not be construed as indicating or implying relative importance, nor as indicating or implying order.

[0033] In specific embodiment one, such as Figure 1 As shown, this invention proposes a data interaction method between an intelligent alarm information management terminal and an alarm host, comprising the following steps:

[0034] Step 1: The intelligent alarm information management terminal and the alarm host are pre-configured with a hierarchical reference dictionary and an extended dictionary is maintained synchronously based on historical interaction data. The strings in the alarm information are matched with the hierarchical reference dictionary and the extended dictionary. If a match is successful, the corresponding dictionary index is output. For numerical data in the alarm information, a numerical identifier is output and binary data converted according to a preset point quantization rule is appended. Together, they form a compressed data stream.

[0035] In this invention, front-end devices such as detectors, infrared sensors, and door magnetic sensors are connected to a back-end alarm host via wired connections. The alarm host aggregates and / or analyzes the signals to generate alarm information, which is then transmitted to an intelligent alarm information management terminal via network cables, and simultaneously to a server or remote monitoring platform. The intelligent alarm information management terminal includes, but is not limited to, mobile devices such as smartphones and tablets, and can also be a PC. Through the intelligent alarm management terminal, users can monitor alarm status in real time, and the server or remote monitoring platform records alarm information for traceability. In a more specific embodiment, the intelligent alarm information management terminal is a device carried by security personnel, enabling them to receive alarm information in real time and react quickly. The alarm host is preferably an edge device.

[0036] The hierarchical baseline dictionary is preferably a static dictionary with a two-layer structure. The first layer stores general category fields in the alarm information, such as area, device type, and event type. The second layer stores specific values ​​for the corresponding category, such as living room, smoke sensor, and fire alarm. The extended dictionary is preferably a dynamic dictionary, managed using the LRU algorithm. When a terminal encounters a new string not included in the baseline dictionary, it sends it in plaintext for the first time. Upon receiving it, the alarm host and the terminal synchronously store the string and its newly assigned dictionary index into their respective extended dictionaries. Figure 2 As shown. String matching follows the longest match principle, prioritizing the search for the longest matching prefix string in the dictionary. For numerical data, such as a temperature of 25.7 degrees Celsius, the preset fixed-point quantization rule is to multiply by 10 and round down to the nearest integer 257, then convert it to a 16-bit binary number. During encoding, a reserved special dictionary index is first output as a numerical identifier, such as FFFF, followed immediately by the 16-bit binary data. Upon reading this identifier, the receiver knows that the subsequent data is a numerical value rather than a dictionary index, such as... Figure 3 As shown. In an optional embodiment, the binary data is further encrypted using methods including, but not limited to, symmetric and asymmetric encryption.

[0037] Step 2: Based on the message sequence number and timestamp bound to the pre-shared key and the alarm information service priority level, generate a transformation key; use the transformation key to derive the shift amount, and perform a cyclic bit shift operation on the dictionary index in the compressed data stream to obtain an encrypted compressed data stream, wherein the numerical identifier and the binary data do not participate in the shift operation;

[0038] The HMAC-SHA256 algorithm is preferred. The pre-shared key is used as the key, and the concatenation of the message sequence number and timestamp is used as the message. A 256-bit hash value is calculated as the transformation key. The last 8 bits of the hash value are taken, converted into an integer, and then modulo 16 to obtain an integer between 0 and 15 as the shift amount. For each 16-bit dictionary index in the compressed data stream, a circular left or right shift is performed by the number of bits specified by the shift amount, while the numerical identifier FFFF and the subsequent binary data remain unchanged.

[0039] Step 3: The terminal places the encrypted and compressed data stream in the payload of the CoAP message and sets a custom Option containing the service priority level and message sequence number in the Option field of the CoAP message;

[0040] The generated encrypted compressed data stream is directly filled into the Payload area of ​​the CoAP message; a privately reserved Option number in the CoAP protocol, such as 2050, is selected as the custom Option; the value of this Option is one byte, where the high 2 bits are used to indicate the business priority level, such as 00 for high, 01 for medium, and 10 for low, and the last 6 bits are used to store the message sequence number of the current priority.

[0041] Step four: The terminal maintains independent round-trip time (RTT) and retransmission timeout (RTO) for different service priority levels; after sending the CoAP message, if no ACK confirmation is received from the alarm host within the RTO corresponding to the current service priority level, a retransmission is performed; when an ACK confirmation message is received from the alarm host, the RTT and RTO of the corresponding service priority level are updated according to the reception time of the ACK and the alarm host queue load factor carried therein.

[0042] For each service priority level, upon receiving an ACK, the sampled RTT (SampleRTT) is first calculated, which is equal to the ACK reception time minus the message transmission time. Then, the smoothed RTT (SRTT) is updated, with the new SRTT equal to the old SRTT × coefficient α + SampleRTT × (1-α). Next, the RTT deviation (RTTVAR) is updated. Finally, a new retransmission timeout (RTO) is calculated, which in one embodiment is equal to SRTT plus four times RTTVAR, with an additional adjustment term proportional to the alarm host queue load factor L. The load factor is returned by the alarm host in the custom option of the ACK message, thus enabling the RTO to reflect the real-time processing capability of the alarm host.

[0043] In a more specific embodiment, the hierarchical reference dictionary includes a static core dictionary layer and a semi-static application dictionary layer; the static core dictionary layer contains fixed general terms in alarm services; the semi-static application dictionary layer contains proprietary terms that remain unchanged for a period of time under specific application scenarios.

[0044] Layered design can improve compression efficiency and adaptability. For example, a static core dictionary layer can contain terms common to fire alarm systems, such as fire alarm, fault, start, and recovery, which are applicable to all projects. A semi-static application dictionary layer, on the other hand, is designed for specific projects. For example, a large shopping mall project might contain terms like "Building A," "Building B," "fire pump," and "smoke exhaust fan." These terms are stable within the shopping mall project but not applicable to other projects, such as a chemical plant.

[0045] In a more specific embodiment, the preset point quantization rule is as follows: multiply the numerical data by a preset quantization factor, round it down, and then convert the resulting integer into a 16-bit binary two's complement form.

[0046] Efficiently converting floating-point numbers to fixed-length integers can reduce the amount of data. For example, a temperature sensor reports a value of 25.43 degrees Celsius. Multiplying this by a quantization factor of 100 yields the integer 2543. Converting this integer 2543 to its 16-bit two's complement form 0000100111101111 retains two decimal places while unifying the original floating-point number into 16-bit data that is easier to process and transmit.

[0047] To ensure that each message is transformed using a unique key and to enhance security, in a more specific embodiment, the generation of the transformation key based on the message sequence number and timestamp bound to the pre-shared key and the alarm information service priority level is specifically as follows:

[0048] The pre-shared key is used as the master key of the HMAC-SHA256 hash function. The message sequence number and timestamp are concatenated to form the message as input. The calculated 256-bit hash value is the transformation key.

[0049] Assuming the pre-shared key is a fixed 128-bit key, the current message sequence number is 105, and the timestamp is 1678886400, concatenate 105 and 1678886400 into a data string. Use the pre-shared key as the HMAC-SHA256 key to calculate a 256-bit hash value on this data string. This hash value is the dynamic transformation key for this message transmission.

[0050] In a more specific embodiment, performing a cyclic bit shift operation on the dictionary indexes in the compressed data stream to obtain the encrypted compressed data stream specifically involves:

[0051] The value of the lowest 4 bits of the transformation key is used as the shift amount;

[0052] For each 12-bit dictionary index in the compressed data stream, a left circular bit shift specified by the shift amount is performed.

[0053] This embodiment provides a lightweight data scrambling encryption. For example, if the lowest 4 bits of the generated dynamic transformation key are 1011, then its corresponding decimal value is 11, which is the shift amount. For a 12-bit dictionary index 000100100011 in the compressed stream, it will be cyclically shifted left 11 times to obtain the new data 110001001000, thereby obfuscating the original data without increasing too much computational overhead.

[0054] In a more specific embodiment, the custom option set in the Option field of the CoAP message uses the reserved Option number 2048; the value of the custom option is a 2-byte field, where the high 2 bits are used to represent the service priority level and the low 14 bits are used to represent the message sequence number.

[0055] The CoAP message structure is as follows: Figure 4 As shown, for a high-priority business message, its priority level can be represented as binary 10. If its message sequence number is 5000, then its 14-bit binary representation is 01001110001000. These two binary arrays are combined into a 16-bit (2-byte) data set, 1001001110001000. This data is used as the Option value and is sent along with Option number 2048 in the Option field of the CoAP message.

[0056] In a more specific embodiment, updating the RTT and RTO of the corresponding service priority level based on the reception time of the ACK and the alarm host queue load factor carried therein specifically involves:

[0057] After receiving the ACK message from the alarm host, calculate the Sample Round Trip Time (SampleRTT) for this message;

[0058] According to the formula Update round-trip time deviation RTTVAR, These are the weighting coefficients;

[0059] According to the formula Update the weighted average round-trip time (SRTT);

[0060] According to the formula Update retransmission timeout RTO, where It equals the alarm host queue load factor multiplied by a preset time coefficient. , These are the weighting coefficients; SRTT is the average round-trip time. The SRTT value before the update. The updated SRTT value, where RTTVAR is the round-trip time offset. The RTTVAR value before the update. The new RTTVAR value calculated this time, RTO new This is the updated retransmission timeout (RTO) value.

[0061] Preferably , Taking this preferred weighting coefficient as an example, let's assume that the current weighted average round-trip time of a certain priority service is... Round-trip time deviation is 100 milliseconds. The original value was 15 milliseconds. The measured sample round-trip time (SampleRTT) was 120 milliseconds. Therefore, the new... The new one is 16.25 milliseconds. The timeout is 102.5 milliseconds. If the alarm host load factor is 0.5 and the preset time coefficient is 10 milliseconds, then the load adjustment time is 5 milliseconds, and the calculated new retransmission timeout is... The timeout is 172.5 milliseconds, which allows the retransmission strategy to more accurately reflect the current network congestion and the processing capacity of the alarm host.

[0062] In a second specific embodiment, a data interaction system between an intelligent alarm information management terminal and an alarm host is provided, comprising:

[0063] The compression unit, intelligent alarm information management terminal, and alarm host are pre-set with a hierarchical reference dictionary and synchronously maintain an extended dictionary based on historical interaction data; the string in the alarm information is matched with the hierarchical reference dictionary and the extended dictionary, and if the match is successful, the corresponding dictionary index is output; for numerical data in the alarm information, a numerical identifier is output and binary data converted according to a preset point quantization rule is appended; together they form a compressed data stream;

[0064] The encryption unit generates a transformation key based on the message sequence number and timestamp bound to the pre-shared key and the priority level of the alarm information service; it uses the transformation key to derive the shift amount and performs a cyclic bit shift operation on the dictionary index in the compressed data stream to obtain an encrypted compressed data stream, wherein the numerical identifier and the binary data do not participate in the shift operation;

[0065] The data packet generation unit, wherein the terminal places the encrypted and compressed data stream in the payload portion of the CoAP message, and sets a custom Option containing the service priority level and message sequence number in the Option field of the CoAP message;

[0066] The transmission unit, wherein the terminal maintains independent round-trip time (RTT) and retransmission timeout (RTO) for different service priority levels; after sending the CoAP message, if no ACK message is received from the alarm host within the RTO corresponding to the current service priority level, a retransmission is performed; when an ACK message is received from the alarm host, the RTT and RTO of the corresponding service priority level are updated according to the reception time of the ACK and the alarm host queue load factor carried therein.

[0067] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0068] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the descriptions in the method embodiments. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0069] The method and electronic device for providing product object information provided in this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the method and its core ideas. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for data interaction between an intelligent alarm information management terminal and an alarm host, characterized in that, The steps include: The intelligent alarm information management terminal and alarm host are pre-set with a hierarchical reference dictionary and synchronously maintain an extended dictionary based on historical interaction data; the string in the alarm information is matched with the hierarchical reference dictionary and the extended dictionary, and if the match is successful, the corresponding dictionary index is output; for numerical data in the alarm information, the numerical identifier is output and binary data converted according to the preset point quantization rules is appended. Together they form a compressed data stream; A transformation key is generated based on the message sequence number and timestamp bound to the pre-shared key and the priority level of the alarm information service. The shift amount is derived using the transformation key, and a cyclic bit shift operation is performed on the dictionary index in the compressed data stream to obtain an encrypted compressed data stream, wherein the numerical identifier and the binary data do not participate in the shift operation; The terminal places the encrypted and compressed data stream in the payload portion of the CoAP message and sets a custom Option in the Option field of the CoAP message, which includes the service priority level and the message sequence number. The terminal maintains independent Round-Trip Time (RTT) and Retransmission Timeout (RTO) for different service priority levels. After sending the CoAP message, if no ACK confirmation is received from the alarm host within the RTO corresponding to the current service priority level, a retransmission is performed. When an ACK confirmation message is received from the alarm host, the RTT and RTO of the corresponding service priority level are updated according to the reception time of the ACK and the alarm host queue load factor carried therein.

2. The data interaction method according to claim 1, characterized in that, The hierarchical reference dictionary includes a static core dictionary layer and a semi-static application dictionary layer; the static core dictionary layer contains fixed and unchanging general terms in alarm services; the semi-static application dictionary layer contains proprietary terms that remain unchanged for a period of time under specific application scenarios.

3. The data interaction method according to claim 1, characterized in that, The preset point quantization rule is as follows: multiply the numerical data by a preset quantization factor, round down, and then convert the resulting integer into a 16-bit binary two's complement form.

4. The data interaction method according to claim 1, characterized in that, The process of generating a transformation key based on the message sequence number and timestamp bound to the pre-shared key and the priority level of the alarm information service is as follows: The pre-shared key is used as the master key of the HMAC-SHA256 hash function. The message sequence number and timestamp are concatenated to form the message as input. The calculated 256-bit hash value is the transformation key.

5. The data interaction method according to claim 1, characterized in that, The step of performing a cyclic bit shift operation on the dictionary indexes in the compressed data stream to obtain the encrypted compressed data stream is as follows: The value of the lowest 4 bits of the transformation key is used as the shift amount; For each 12-bit dictionary index in the compressed data stream, a left circular bit shift specified by the shift amount is performed.

6. The data interaction method according to claim 1, characterized in that, The custom option set in the Option field of the CoAP message uses the reserved Option number 2048; the value of the custom option is a 2-byte field, where the high 2 bits are used to represent the service priority level and the low 14 bits are used to represent the message sequence number.

7. The data interaction method according to claim 1, characterized in that, The step of updating the RTT and RTO of the corresponding service priority level based on the reception time of the ACK and the alarm host queue load factor carried therein is as follows: After receiving the ACK message from the alarm host, calculate the Sample Round Trip Time (SampleRTT) for this message; According to the formula Update round-trip time deviation RTTVAR; According to the formula Update the weighted average round-trip time (SRTT); According to the formula Update retransmission timeout RTO, where It equals the alarm host queue load factor multiplied by a preset time coefficient. , These are the weighting coefficients; SRTT is the average round-trip time. The SRTT value before the update. The updated SRTT value, where RTTVAR is the round-trip time offset. The RTTVAR value before the update. The new RTTVAR value calculated this time, RTO new This is the updated retransmission timeout (RTO) value.

8. A data interaction system between an intelligent alarm information management terminal and an alarm host, characterized in that: include: The compression unit, intelligent alarm information management terminal and alarm host are pre-set with a hierarchical reference dictionary and synchronously maintain an extended dictionary according to historical interaction data; the string in the alarm information is matched with the hierarchical reference dictionary and the extended dictionary, and if the match is successful, the corresponding dictionary index is output; for numerical data in the alarm information, the numerical identifier is output and binary data converted according to the preset point quantization rules is appended. Together they form a compressed data stream; The encryption unit generates a transformation key based on the message sequence number and timestamp bound to the pre-shared key and the priority level of the alarm information service; The shift amount is derived using the transformation key, and a cyclic bit shift operation is performed on the dictionary index in the compressed data stream to obtain an encrypted compressed data stream, wherein the numerical identifier and the binary data do not participate in the shift operation; The data packet generation unit, wherein the terminal places the encrypted and compressed data stream in the payload portion of the CoAP message, and sets a custom Option containing the service priority level and message sequence number in the Option field of the CoAP message; The transmission unit, wherein the terminal maintains independent round-trip time (RTT) and retransmission timeout (RTO) for different service priority levels; after sending the CoAP message, if no ACK confirmation is received from the alarm host within the RTO corresponding to the current service priority level, a retransmission is performed; when an ACK confirmation message is received from the alarm host, the RTT and RTO of the corresponding service priority level are updated according to the reception time of the ACK and the alarm host queue load factor carried therein.

9. The data interaction system according to claim 8, characterized in that, The hierarchical reference dictionary includes a static core dictionary layer and a semi-static application dictionary layer; the static core dictionary layer contains fixed and unchanging general terms in alarm services; the semi-static application dictionary layer contains proprietary terms that remain unchanged for a period of time under specific application scenarios.

10. The data interaction system according to claim 8, characterized in that, The preset point quantization rule is as follows: multiply the numerical data by a preset quantization factor, round down, and then convert the resulting integer into a 16-bit binary two's complement form.

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