CN112929938B

CN112929938B - AP topological relation graph generation method and system based on wireless log information

Info

Publication number: CN112929938B
Application number: CN202110114017.XA
Authority: CN
Inventors: 肖明; 周东波; 肖毅; 郭晓威; 周伟; 史永银
Original assignee: Central China Normal University
Current assignee: Central China Normal University
Priority date: 2021-01-27
Filing date: 2021-01-27
Publication date: 2022-05-03
Anticipated expiration: 2041-01-27
Also published as: CN112929938A

Abstract

The invention relates to a method and a system for generating an AP topological relation graph based on wireless log information, comprising a line log analysis module and an AP topological graph generation module, wherein the wireless log analysis module is used for counting and analyzing the wireless log information between a terminal and an AP, and extracting an interaction record of the terminal and the AP and an AP set in an active state in an interaction process; and the AP topological graph generating module is used for judging the adjacent relation between the APs in the active state according to the interaction records of the terminal and the APs and generating an AP topological relation graph. The AP topological relation graph generated by the system only depends on wireless log information, and compared with other methods, the method has smaller extra human and material cost and is simple and practical to realize.

Description

AP topological relation graph generation method and system based on wireless log information

Technical Field

The invention relates to the technical field of wireless communication, in particular to a method and a system for generating an AP topological relation graph based on wireless log information.

Background

With the development of the times, wireless network technology is rapidly popularized, and wireless network systems are built in many places. Many areas are equipped with a large number of Access Points (APs) in order to achieve full coverage of wireless signals.

The two-dimensional geographic location distribution map of the AP can well describe the condition of the AP to help the planning of the wireless network system, but the manufacturing of the two-dimensional geographic location distribution map requires a lot of manpower and material resources, and the method using the two-dimensional geographic location distribution map also has a certain problem because the two-dimensional geographic location distribution map is usually in units of areas, and although the adjacent condition of the AP in the area can be well described through the two-dimensional geographic location distribution map, the adjacent condition of the AP between the areas cannot be processed. Moreover, in many cases, the arrangement of the APs only considers the even distribution in geography, so that the problem of poor use experience may exist in parts of areas with high people stream density.

The AP topology map can describe the neighboring relationship between APs and the current real-time attributes of the APs. Besides planning of a wireless network system, many aspects of research such as device positioning, trajectory prediction of devices and the like need to be supported by an AP topology. The AP topology map is an alternative to the two-dimensional geographic location profile of the AP.

Besides generating the AP topology map by using the two-dimensional geographic location distribution map, the current method for generating the AP topology map mainly needs human intervention, such as determining the adjacent relationship of the APs one by using a wireless signal detector. Although such a method can obtain accurate neighbor information, it consumes a relatively large amount of manpower. When the geographic environment is complex, such as an indoor environment, there are many obstacles, and the distance concept in space cannot accurately generate the topological relation. This makes it necessary to perform additional verification work in order to ensure the accuracy of the topological relation, not to mention when the geographical location information is not complete.

Disclosure of Invention

Aiming at the technical problems in the prior art, the invention provides a method and a system for generating an AP (access point) topological relation based on wireless log information. The wireless log information contains a large amount of interaction information of the AP and the terminal, and the terminal only interacts with the AP with the strongest signal in most cases, so that the wireless log information can describe the topological relation between the APs more accurately than the geographic information. The AP topological relation graph generated by the system only depends on wireless log information, and compared with other methods, the method has smaller extra human and material cost and is simple and practical to realize.

The technical scheme for solving the technical problems is as follows:

in one aspect, the present invention provides a method for generating an AP topological relation graph based on wireless log information, including the following steps:

counting and analyzing wireless log information between a terminal and an AP (access point), and extracting an interaction record of the terminal and the AP and an AP set in an active state in an interaction process;

and judging the adjacent relation between the APs in the active state according to the interaction records of the terminal and the APs, and generating an AP topological relation graph.

Further, the wireless log information includes a wireless signal interaction log between the terminal and the AP, an authentication log of the terminal logging in the AP, and a roaming log of the terminal;

the wireless signal interaction log between the terminal and the APs is used for recording that the terminal and the APs perform wireless signal interaction simultaneously in a specified time period;

the terminal logs in an authentication log of the AP and is used for recording that the terminal and only one AP generate authentication information in a specified time period;

the roaming log of the terminal is used for recording the condition that the AP connected is changed due to the change of the position of the terminal or the overlarge load of the AP connected currently.

Further, the extracting the interaction record of the terminal and the AP includes:

aiming at wireless signal interaction logs between a terminal and APs, generating adjacent basis records for the APs according to log information, wherein the adjacent basis records comprise time generated by each log, unique identification codes of the APs and signal strength of interaction between each AP and the terminal;

aiming at an authentication log of a terminal logging in an AP, generating a logging basis record for the AP according to log information; the login basis is used for counting the load condition of the AP, and the log generation time and the unique identification code of the AP are contained in the login basis record;

aiming at a roaming log of a terminal, generating a roaming basis record for the AP according to log information; the roaming basis record contains the log generation time and a unique identification code related to the AP.

Further, the set of APs in an active state during the interaction process includes generating APs corresponding to the identification codes recorded during the recording process.

Further, the determining the neighboring relationship between APs in an active state according to the interaction records between the terminal and the APs includes:

1) regarding the adjacent basis records, if the generation time of the adjacent basis records of a plurality of APs is less than a specified time interval, the APs are considered to possibly have adjacent relations;

2) regarding the login basis record, if the time interval between the generation time of the login basis record of the current AP and the adjacent basis record generation time of one or more APs is less than a specified time interval, the current AP and the one or more APs are considered to possibly have an adjacent relation;

3) for the roaming basis record, the APs involved in the roaming basis record may have a neighbor relation;

4) when judging that the adjacent relation possibly exists between the APs, generating a new record, wherein the record at least comprises the occurrence time of the adjacent relation, the unique identification code of the AP related to the adjacent relation and data utilized for judging the adjacent relation.

Further, the determining, according to the interaction record between the terminal and the AP, an adjacent relationship between APs in an active state, and further performing regularity determination on an adjacent relationship determination result, where the determination rule includes:

A) regarding any two APs, when the adjacent relation judgment times of the two APs exceed a preset threshold value, the two APs are considered to be adjacent;

B) on the basis of A), when the adjacent relation judgment times exceed a preset threshold value in a set time period, the two APs are considered to be adjacent;

C) on the basis of A), when the AP signal intensity in the adjacent record meets the set relationship, the adjacent relationship is considered to be effective;

D) based on the limitation of the known geographic information, the neighboring relationship is considered invalid when there is a difference in the area where the geographic location of the AP where the neighboring relationship may exist is located.

In another aspect, the present invention provides a system for generating an AP topological relation graph based on wireless log information, including: the system comprises a wireless log analysis module and an AP topological graph generation module;

the wireless log analysis module is used for counting and analyzing wireless log information between the terminal and the AP, and extracting interaction records of the terminal and the AP and an AP set in an active state in an interaction process;

and the AP topological graph generating module is used for judging the adjacent relation between the APs in the active state according to the interaction records of the terminal and the APs and generating an AP topological relation graph.

The invention has the beneficial effects that: the invention mainly generates the AP topological graph through the wireless log information and eliminates the accidental problems existing in the wireless log information through a statistical strategy, thereby accurately generating and updating the AP topological graph in real time. The reliability of the system depends on the number of terminals in the wireless network system, and the system is suitable for scenes with large people stream density and large range, such as numerous colleges and universities. In such a scenario, the idea of generating the AP topological graph based on the wireless log information has a great advantage compared with the similar method, the adjacent relationship between APs can be accurately determined by means of sufficient people stream density, and meanwhile, the change of the AP state can be automatically detected. The system has good mobility, and can only adapt to different scenes by simple adjustment.

Drawings

Fig. 1 is a schematic diagram of a process of generating an AP topology diagram according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a system architecture according to an embodiment of the present invention.

Detailed Description

The principles and features of this invention are described below in conjunction with the following drawings, which are set forth by way of illustration only and are not intended to limit the scope of the invention.

The embodiment of the invention provides an AP topological graph generating system based on a wireless log, as shown in FIG. 2, the system is easy to realize and maintain, and can realize the generation and the update of the AP topological graph with smaller space and time expenditure. The system mainly uses the terminal as a visual angle to search for the adjacent AP. And finally, eliminating the randomness existing in the view angle of a single terminal according to the observation results of the plurality of terminals, and further completing the generation and the updating of the AP topological graph.

Before introducing the present system, it is necessary to explain the terms referred to herein:

AP topological relation: strictly speaking, the topological relation here does not mean a spatial distance, but whether or not coverage areas of wireless signals overlap between APs. Generally, APs with overlapping information coverage areas are close in their spatial distance.

A terminal: the electronic product enjoying wireless WIFI service, such as a mobile phone, a computer and the like.

The system mainly comprises two parts, namely a wireless log analysis module and an AP topological graph generation module.

We refer to all the neighboring relationships between APs as the edge set of the topology, and, in contrast, all APs as the point set of the topology. The wireless log analysis module needs to provide the information needed to determine the set of topology points and the set of edges. For the information for determining the neighboring relationship between APs, i.e. the edge set of the topology map, the main method is as follows:

(1) and confirming effective information contained in the wireless log information, wherein the wireless log information comprises but is not limited to a wireless signal interaction log between the terminal and the AP, an authentication log of the terminal logging in the AP and a roaming log of the terminal.

(2) In the information interaction log, there is a log describing wireless signal interaction of the terminal with the AP, which means that their distance in space is small if the AP and the terminal can perform signal interaction. Thus, if a terminal performs wireless signal interaction with multiple APs within a short period of time, the distance between the APs must also be small. At this time, the neighbor basis records are generated for the APs having small distances. The neighbor dependency record includes the time of each log generation, the unique identification code of the AP, and the signal strength of each AP interacting with the terminal.

The method comprises the following steps that (3) an authentication log of a terminal logging in an AP represents an event that the terminal completes user logging in through the AP so as to obtain the internet access authority, in general, the terminal can only generate authentication information with one AP within a period of time, the authentication AP is responsible for providing network service, when the authentication log appears in a wireless log, a logging basis record is generated for the AP, the logging basis is used for counting the load condition of the AP, the time of log generation is recorded, and the unique identification code of the AP is recorded.

(4) The roaming log of the terminal indicates that the terminal is provided with network service by other APs due to a change in location, an excessive load of the authentication AP, or the like. The roaming log is a supplement to the authentication log, aiming to determine more precisely which AP the terminal is served by. And when the roaming log appears in the wireless log, generating a roaming basis record for the AP related in the wireless log. The roaming criteria includes a log generation time, a unique identification code related to the AP.

(5) Considering that different wireless log systems can generate different wireless log information, for the log types not mentioned above, if the log information can also generate some basis, the information can be treated as effective information.

All of the above mentioned references record the information needed to generate the AP topology.

For the point set of the topology map, i.e. all valid APs, since the APs may be damaged, malfunction, withdrawn, etc., the point set of the topology map cannot be inferred simply by the edge set, which requires the module to record the active APs as well. Namely, in the process of processing the wireless log, an active state table of the AP is established. The updating mode is that the AP is considered to be in an active state and the last active time is updated when the unique identification of the AP appears in the processing process. Thus, the set of points of the topology map may be determined by the AP active table.

And the AP topological graph generating module generates the AP topological graph according to the record obtained by the wireless log analyzing module. The module determines whether there is a neighbor relationship between APs in the following manner.

(1) For neighbor dependency records, when the generation time between logs is less than 5 seconds or other time interval, it is assumed that a neighbor relationship may exist between these APs.

(2) For the log-on basis record, when the log time of the adjacent basis record and the time interval of the log-on basis record are less than 5 seconds or other time intervals, the APs and the log-on APs are considered to have the adjacent relation.

(3) For roaming compliance records, it is assumed that the involved APs may have a neighbor relationship.

(4) When the adjacent relation between the APs is judged to exist, a new record is generated, and the record at least comprises the occurrence time of the adjacent relation, the unique identification code of the AP related to the adjacent relation and the basis for judging the adjacent relation.

The reason why the system cannot directly judge whether the adjacent relation exists according to the above basis is that the wireless log information may have contingency and inaccuracy, for example, the position of the terminal may be changed greatly at a time interval of 5 seconds, for example, when the terminal is dropped from the roof or the terminal is on the automobile. Obviously in these cases, the neighbor relation is not satisfied depending on the involved APs. The module then needs to use some rules to exclude some haphazard neighborhood. The most basic rule is a rule on a threshold, i.e. the number of neighbours should be at least greater than a certain constant in order to consider them as neighbours. In addition, the system contains other rules:

(1) a time limit is added based on a threshold, such as the number of adjacent relationships that occurred within the last two weeks.

(2) Adding signal strength limit on the basis of the threshold value, and considering that the secondary adjacent relation is effective when the adjacent AP signal strength recorded according to the record meets a certain number relation. Such as the sum of the signal strengths of the APs being less than 80 or the sum of the squares of the signal strengths being less than 2000. (the unit of signal strength is (-dbm), so that a smaller number represents a stronger signal strength, and a stronger signal strength represents a smaller distance between them)

(3) Based on the restriction of the known geographical information, the secondary neighbor relation is considered invalid when there is a difference in geographical location information between APs intuitively. The rule has certain subjectivity, and the geographical position information can indicate the distance between the APs in reality to a certain extent. Such a proximity relationship is considered invalid when the actual distances between APs are unlikely to be such that they satisfy the proximity relationship, or when it is recognized for administrative convenience that no proximity relationship exists between APs, for example, when APs are distributed in different buildings or areas.

After the generation of the edge set is completed, the point set of the topological graph also needs to be generated. All APs contained in the AP active table are used here to generate the set of points of the topology map. Meanwhile, the APs are classified into multiple classes according to the last active time of the APs, and the classes are used for distinguishing the APs with problems. At this time, after the point set is determined, the generation of the AP topological graph can be completed.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A method for generating an AP topological relation graph based on wireless log information is characterized by comprising the following steps:

judging the adjacent relation between the APs in the active state according to the interaction records of the terminal and the APs, and generating an AP topological relation graph;

the wireless log information comprises a wireless signal interaction log between the terminal and the AP, an authentication log of the terminal logging in the AP and a roaming log of the terminal;

the roaming log of the terminal is used for recording the condition that the AP connected is changed due to the change of the position of the terminal or the overlarge load of the AP connected currently;

the extracting of the interaction record of the terminal and the AP comprises the following steps:

2. The method of claim 1, wherein the set of APs in an active state during the interaction comprises generating APs corresponding to identification codes recorded during the recording.

3. The method according to claim 1, wherein said determining the neighboring relationship between APs in an active state according to the interaction record between the terminal and the AP comprises:

4. The method according to claim 3, wherein said determining the neighboring relationship between APs in an active state according to the interaction records between the terminal and the APs further comprises performing a regularity determination on the result of the neighboring relationship determination, and the determination rule includes:

5. An AP topological relation graph generation system based on wireless log information is characterized by comprising: the system comprises a wireless log analysis module and an AP topological graph generation module;

the AP topological graph generating module is used for judging the adjacent relation between the APs in the active state according to the interaction records of the terminal and the APs and generating an AP topological relation graph;

6. The system of claim 5, wherein the set of APs that are active during the interaction process comprises generating APs that correspond according to the identification codes recorded during the recording process.