CN110996268B

CN110996268B - SIG mesh-based broadcast bearer layer message filtering strategy method

Info

Publication number: CN110996268B
Application number: CN201911276895.0A
Authority: CN
Inventors: 徐超; 张昭; 谢如昕
Original assignee: Shanghai Panchip Microelectronics Co ltd
Current assignee: Shanghai Panchip Microelectronics Co ltd
Priority date: 2019-12-12
Filing date: 2019-12-12
Publication date: 2021-09-24
Anticipated expiration: 2039-12-12
Also published as: CN110996268A

Abstract

The invention discloses a method for filtering messages of a broadcast bearing layer based on SIG mesh, which is based on a Bluetooth SIG mesh network, wherein the mesh network comprises a bearer layer, a network layer, a transport layer and an access layer, the bearer layer transmits data among mesh nodes and transmits the data to the network layer, the mesh nodes receive the broadcast messages on the bearer layer, and the broadcast messages are compared with a preset queue to filter the broadcast messages in the mesh network, so that the consumption of an RAM (random access memory) and the execution time of a CPU (central processing unit) are reduced. The invention optimizes the RAM and CPU execution time and BLE scanning time consumed by the interference of the air non-mesh broadcast packet, and optimizes the RAM consumption and CPU execution time caused by repeated data packets.

Description

SIG mesh-based broadcast bearer layer message filtering strategy method

Technical Field

The invention relates to the technical field of Bluetooth SIG mesh, in particular to a method for filtering messages of a broadcast bearing layer based on the SIG mesh.

Background

At present, more and more devices are networked through the Bluetooth mesh, and the network scale is larger and larger. A home may also have hundreds of mesh nodes, such as a smart lamp, a smart socket, a smart fan, etc., however, each manufacturer may repeatedly send the same data packet for a plurality of times in order to stably control the operation of the device, for example, a makita's sprite turns on the smart lamp to send about 10 identical data packets, and these 10 messages are forwarded and spread by other devices in the room, which may result in a very large number of data packets in the air, and thus for a Micro Controller Unit (MCU) with low processing capability and low RAM, it is a very large burden to receive and process these data messages.

At present, many Bluetooth chips are Low-speed microprocessor chips, if a mesh node developed by these chips receives a Bluetooth broadcast message through a Low power consumption Bluetooth (BLE) protocol stack standard, it takes a lot of time to know whether the broadcast message is a mesh message, which may cause a load of a CPU, and a BLE frequent interruption callback may also shorten a time for BLE scanning.

The BLE mesh devices on the market can transmit the same data messages for multiple times in order to improve the quality of the broadcast messages, and when the network scale is large, the same data messages are increased. When the BLE mesh device scans that the messages need to be cached in the RAM and then transferred to the network layer, redundant data messages are discarded. This results in a very large RAM overhead, which is not manageable for a typically small embedded system. Meanwhile, each data packet can only know whether to discard the data packet by carrying out AES-CCM decryption on a network layer, and the same data message processing greatly improves the load of a CPU.

Therefore, those skilled in the art are dedicated to develop a method for SIG mesh based broadcast bearer (bearer) layer packet filtering policy, which minimizes these burdens.

Disclosure of Invention

In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is how to reduce the burden of receiving and processing broadcast data packets by the bluetooth SIG mesh node device.

In order to achieve the above object, the present invention provides a method for a broadcast bearer layer packet filtering policy based on SIG mesh, which is characterized in that the method is based on a bluetooth SIG mesh network, the mesh network includes a bearer layer, a network layer, a transport layer, and an access layer, the bearer layer transmits data between mesh nodes and transmits the data to the network layer, the mesh nodes receive broadcast packets on the bearer layer, and the broadcast packets are compared with a preset queue to filter the broadcast packets in the mesh network, thereby reducing the consumption of RAM and the execution time of CPU.

Further, the filtering of the broadcast message in the mesh network includes filtering of a non-mesh broadcast message and filtering of a duplicate mesh broadcast message.

Further, the filtering of the non-mesh broadcast packet includes the following steps:

step 1.1, setting a broadcast identifier corresponding to the mesh broadcast message;

step 1.2, the mesh node records the broadcast identifier into the queue;

step 1.3, comparing the broadcast message received by the mesh node with the queue;

and step 1.4, if the queue has the broadcast identifier of the broadcast message received by the mesh node, receiving the broadcast message, otherwise, discarding the broadcast message.

Furthermore, the implementation manner of filtering the non-mesh broadcast message includes an application program interface, digital circuit hardware, and a host control interface.

Further, the filtering of the duplicate mesh broadcast message includes the following steps:

step 2.1, initializing the queue, wherein the queue comprises a plurality of elements, and the elements comprise a digital fingerprint and original data with a certain length;

step 2.2, solving the digital fingerprint of the broadcast message data packet received by the mesh node;

step 2.3, forming an element by the digital fingerprint and original data with a certain length;

step 2.4, comparing the elements formed in the step 2.3 with all the elements in the queue, if the elements are the same, discarding the repeated packet, and turning to the step 2.6, otherwise, receiving the broadcast message;

step 2.5, pushing the elements formed in the step 2.3 into a queue;

and 2.6, repeating the steps 2.2 to 2.5.

Further, the depth of the queue is 5 to 50.

Further, the depth of the queue is 10.

Further, the digital fingerprint includes a checksum or a hash value.

Further, the length of the original data is 1 to 3 bytes.

Further, the length of the original data is 3 bytes.

The beneficial technical effects of the invention are as follows:

1. and optimizing the RAM consumed due to the interference of the air non-mesh broadcast packet, the execution time of the CPU and the BLE scanning time.

2. And optimizing the consumption of the RAM and the execution time of the CPU caused by repeated data packets.

The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, the features and the effects of the present invention.

Drawings

FIG. 1 is a block diagram of a non-mesh packet filtering policy flow in accordance with a preferred embodiment of the present invention;

FIG. 2 is a block diagram of a data packet filtering strategy according to a preferred embodiment of the present invention.

Detailed Description

The technical contents of the preferred embodiments of the present invention will be more clearly and easily understood by referring to the drawings attached to the specification. The present invention may be embodied in many different forms of embodiments and the scope of the invention is not limited to the embodiments set forth herein.

The invention adds a strategy for filtering non-mesh messages and repeated mesh messages based on the standard of a broadcast bearing (bearer) layer of SIG mesh.

Example one

Filtering non-mesh broadcast packet policy:

aiming at the interference of other non-mesh broadcasts in the mesh network, the filtering is finished at the fastest speed by a software method.

According to the method, the interference of non-mesh broadcasting is filtered as soon as possible, and a broadcast identifier (adv flag) filter function interface void adv _ flag _ set (agent 8_ t flag) and void adv _ flag _ remove (agent 8_ t flag) are added.

And calling the adv _ flag _ remove function by the user to add a field to the global adv flag queue, and calling the adv _ flag _ remove to remove the same field of the global adv flag queue. The BLE bottom layer data interrupt service starts to receive the broadcast message, compares the adv flag field of the received broadcast message with the adv flag queue set by the user, and if the adv flag field of the received broadcast message does not exist in the adv flag queue set by the user, immediately discards the received broadcast message without reporting to a user interface, so that the CPU time of the user is greatly prolonged, and the time occupied by interrupt is also reduced.

The setting and comparison of the adv flag can also be realized by a digital circuit, or software is realized by a Host Controller Interface (HCI) command. For example, a digital circuit may store the value of the adv flag via 8 32-bit registers, and an independent 32-bit register may enable and disable the register corresponding to the adv flag storage via a bit, in a manner analogous to the filter function interfaces, void adv _ flag _ set (uint8_ t flag) and void adv _ flag _ remove (uint8_ t flag). The mode principle of the software HCI interface is equivalent to the filter function interfaces void adv _ flag _ set (agent 8_ t flag) and void adv _ flag _ remove (agent 8_ t flag).

As shown in fig. 1, the filtering of the non-mesh broadcast packet policy includes the following steps:

1. a user calls an Application Programming Interface (API) function to set an adv flag parameter;

2. the chip records these flags into a queue Q1;

3. the BLE data interruption generates data content marked as A;

4. and judging whether the Q1 has the flag of A, if so, receiving the data message and informing the user through a standard BLE protocol, and if not, discarding the data packet.

Example two

Filtering the repeated data packets in the mesh network:

aiming at the problem that mesh receives the same broadcast message for multiple times, the same data message is filtered through a strategy of software.

The method is suitable for devices which are already connected to the network, and according to the standard of SIG mesh, the serial number (sequence number) of each data packet is different, which means that the content of each data packet is different. Where identical packets are relatively close in time, we can initialize a queue, where each set of data in the queue can be a 16-byte checksum or hash (hash) value of a mesh packet, and 1 to 3 bytes of original data. The checksum of the received data packets is calculated every time, 3 bytes of original data are stored, and the data are pushed into a queue to form an element.

Checksum (or hash value)
	Data0
Data1
	Data2

The depth of the queue can be planned according to the actual network scale and the network node attribute, and is set as 10 by default. These values are calculated when the broadcast packet data is received and compared to all elements in the queue, and if they are the same, the duplicate packet is discarded.

The method of the present invention is an alternative method to the method of the present invention, in which the same data is buffered in the queue, and the same data packet is discarded by comparing the buffered same data in any way. Such as caching all real data or caching the value of the xor sum of the real data, etc.

As shown in fig. 2, filtering the mesh network duplicated data includes the following steps:

1. receiving a mesh broadcast message;

2. calculating a hash value, and storing the hash value and 3 original data into a queue Q1;

3. and judging whether the Q1 has the same data as the tail part of the Q1, if so, receiving the data message, and otherwise, discarding the data message.

The foregoing detailed description of the preferred embodiments of the invention has been presented. It should be understood that numerous modifications and variations could be devised by those skilled in the art in light of the present teachings without departing from the inventive concepts. Therefore, the technical solutions available to those skilled in the art through logic analysis, reasoning and limited experiments based on the prior art according to the concept of the present invention should be within the scope of protection defined by the claims.

Claims

1. A method for filtering messages of a broadcast bearing layer based on SIG mesh is characterized in that the method is based on a Bluetooth SIG mesh network, the mesh network comprises a bearer layer, a network layer, a transport layer and an access layer, the bearer layer transmits data among mesh nodes and transmits the data to the network layer, the mesh nodes receive the broadcast messages on the bearer layer, and the broadcast messages are compared with a preset queue to filter the broadcast messages in the mesh network, so that the consumption of RAM and the execution time of a CPU are reduced;

the filtering of the broadcast message in the mesh network comprises filtering of a non-mesh broadcast message and filtering of a repeated mesh broadcast message;

the filtering of the non-mesh broadcast message comprises the following steps:

step 1.2, the mesh node records the broadcast identifier into the queue;

step 1.4, if the queue has the broadcast identifier of the broadcast message received by the mesh node, receiving the broadcast message, otherwise, discarding the broadcast message;

the specific software implementation mode for filtering the non-mesh broadcast message comprises the following steps:

step S1, the user calls an Application Programming Interface (API) function to set the adv flag parameter;

step S2, recording the flags into a queue Q1 by the chip;

step S3, recording BLE data interruption generation data content as a;

step S4, judging whether Q1 has flag of A, if yes, receiving the broadcast message and informing the user through a standard BLE protocol, otherwise, discarding the broadcast message;

the filtering of the repeated mesh broadcast messages comprises the following steps:

step 2.5, pushing the elements formed in the step 2.3 into a queue;

step 2.6, repeating the steps 2.2 to 2.5;

the specific software implementation mode for filtering the repeated mesh broadcast messages comprises the following steps:

step T1, receiving a mesh broadcast message;

step T2, calculating a hash value, and storing the hash value and 3 original data into a queue Q1;

and step T3, judging whether the Q1 has the same data as the tail part of the Q1, if so, receiving the broadcast message, otherwise, discarding the broadcast message.

2. The SIG mesh-based broadcast bearer layer message filtering strategy of claim 1, wherein the filtering of non-mesh broadcast messages is implemented in a manner comprising an application program interface, digital circuit hardware, and a host control interface.

3. The SIG mesh based broadcast bearer layer packet filtering policy method of claim 1, wherein the depth of the queue is 5 to 50.

4. The SIG mesh-based broadcast bearer layer packet filtering policy method of claim 3, wherein the depth of the queue is 10.

5. The SIG mesh based broadcast bearer layer message filtering strategy method of claim 1, wherein the digital fingerprint comprises a checksum or a hash value.

6. The SIG mesh based broadcast bearer layer packet filtering policy method of claim 1, wherein the original data is 1 to 3 bytes in length.

7. The SIG mesh based broadcast bearer layer packet filtering policy method of claim 6, wherein the original data is 3 bytes in length.