CN116405089A - A path verification method and device for satellite Internet - Google Patents

Abstract

The invention provides a path verification method and a path verification device for satellite Internet, which are used for constructing a global time delay gradient matrix reflecting an implicit mapping relation between data transmission time delay and geographic distance between ground stations, and detecting potential risk paths by clustering abnormal values in the global time delay gradient matrix; and constructing a risk criterion according to physical characteristics of path hijacking attacks in the satellite Internet, and performing risk verification on the potential risk paths according to the risk criterion. The invention replaces the encryption mark matching verification method used by the hop-by-hop verification mechanism, avoids a great deal of expenditure caused by frequent path change under the satellite internet dynamic topology condition, and improves the path verification performance in the satellite internet scene.

Description

A path verification method and device for satellite Internet

technical field

The invention relates to the technical field of satellite communication, in particular to a path verification method and device for satellite Internet.

Background technique

In recent years, the application of low-orbit mega-satellite constellations has provided user terminals accessing the satellite Internet with global coverage and low-latency network services, improving the network experience of user terminals. However, a large number of inter-satellite links are deployed in the low-orbit megasatellite constellation, which makes the low-orbit megasatellite constellation truly networked compared with the satellite communication system using the bent-pipe mode, which means that the low-orbit megasatellite constellation faces Unprecedented threat of cyber attacks. Route hijacking attack is one of the most common network attacks on the Internet at present. Attackers modify the original forwarding path of data packets by various means, making them fall into routing black holes or pass through unsafe areas such as eavesdropping nodes, and damage user data security. Low-orbit giant satellite constellations not only face this problem, but compared with ground nodes with strict security such as data centers, the global exposure of satellite nodes makes them in the field of vision of a huge number of potential attackers. In addition, because the satellite nodes are in the uncontrolled area for a long time and lack ground measurement and control support facilities, it is difficult to perceive and defend in the early stage of the attack. Therefore, it is particularly necessary to detect route hijacking.

Path verification is one of the main means of detecting route hijacking. Its purpose is to enable nodes or terminals to verify whether the upstream forwarding path is consistent with the expected forwarding path, so as to detect such attacks involving path tampering. Most of the existing path verification methods are implemented by using the hop-by-hop verification mechanism, that is, to designate an expected forwarding path for the source end under the implicit assumption that the network topology is stable, generate a shared key between the nodes on the expected forwarding path, and perform a data packet verification on the previous node. The cryptographic operation generates an encrypted mark, and embeds it in the packet header to follow the data forwarding. The next node proves that the data packet has indeed passed the hop-by-hop verification method of the previous node by verifying the encrypted mark, and verifies the consistency between the actual forwarding path and the expected forwarding path. .

However, in the satellite Internet, due to the frequent switching of the satellite-ground link at the minute level, the network topology has been in a state of rapid change, and the routing needs to be re-converged according to the new topology, and the end-to-end no longer has a stable forwarding path. Therefore, when the network topology When changing, the expected forwarding path specified by the source based on the implicit assumption that the previous network topology structure is stable will no longer reflect the current situation, resulting in the loss of stable criteria for path verification. Whenever the satellite-ground link is switched, it is necessary to regenerate the shared key between nodes and re-use the hop-by-hop verification method to verify the consistency of the actual forwarding path and the expected forwarding path; the above series of operations involve multiple signaling interactions and encryption and decryption calculation, resulting in a large amount of signaling overhead and computational overhead. In addition, the perception of network topology changes has a certain lag. In this case, the change of the expected forwarding path cannot be reflected in the encryption mark in time, which will cause the path node to misjudge the data packet and lose the packet. Therefore, how to provide a low-overhead, high-performance path verification scheme in the satellite Internet scenario has become an urgent problem to be solved.

Contents of the invention

The present invention provides a path verification method and device for satellite Internet, by performing cluster analysis on the implicit mapping relationship between the time delay between ground stations and the geographical distance to obtain abnormal values to detect risky paths, instead of hop-by-hop The encryption tag matching verification method used in the verification mechanism uses clustering and physical feature analysis to find the path with an abnormal implicit mapping relationship between delay and geographical distance as the path for routing hijacking, avoiding the existing In path verification technology, under the condition of satellite Internet dynamic topology, frequent path changes cause a lot of signaling overhead and computing overhead.

In a first aspect, the present invention provides a path verification method for satellite Internet, the method comprising:

Generate an inter-station distance matrix according to the geographic location information between ground stations;

Summarize the inter-station delay table of each ground station to obtain the global delay matrix;

Differentiating corresponding elements of the global delay matrix and the inter-station distance matrix to obtain a global delay gradient matrix;

Performing statistical outlier analysis on the global delay gradient matrix, and using the data transmission path of the ground station pair with the outlier as a potential risk path;

When the potential risk path satisfies the first condition, determining the potential risk path as a risk path;

Wherein, the data transmission delay from each target ground station to the ground station is stored in the inter-station delay table of each of the ground stations; the target ground station is a ground station other than the ground station;

The first condition is that the difference between the measured value of the data transmission delay and the theoretical estimated value is greater than the shortest data transmission delay of a round-trip satellite-ground link.

According to the path verification method for satellite Internet provided by the present invention, the generation process of the inter-station delay table of the ground station includes:

Make the ground station locally create 4 inter-station delay sub-tables with the source ground station number and data transmission delay as fields; wherein, the 4 inter-station delay sub-tables and the 4 access satellite orbit directions are respectively Correspondingly, the four kinds of orbit directions of the access satellites are respectively the upper satellite north direction and the lower satellite direction south, the upper satellite direction north and the lower satellite direction north, the upper satellite south direction and the lower satellite north direction, and the upper satellite south direction and the lower satellite direction south;

In a measurement cycle, control each of the target ground stations to send a delay measurement packet to the ground station at intervals of a preset duration; wherein, the delay measurement packet is to carry out the source end ground station number of the IP data packet , The access satellite number of the source ground station and the packet header embedding of the sending time stamp are obtained;

making the ground station estimate the data transmission delay and access satellite orbit direction from each of the target ground stations to the ground station according to the delay measurement packet sent by each of the target ground stations;

Using the number of each target ground station as an index, insert the data transmission delay from each target ground station to the ground station into the access satellite orbit direction from each target ground station to the ground station In the corresponding inter-station delay sub-table, get 4 inter-station delay sub-tables filled with data;

The four inter-station delay sub-tables of the filled data are combined to obtain the inter-station delay table of the ground station.

According to the path verification method for satellite Internet provided by the present invention, according to the measurement packet sent by the target ground station, the data transmission delay from the target ground station to the ground station is estimated, including:

List the duration between the sending time stamp and the receiving time of each measurement packet sent by the target ground station in the first list;

After filtering the multiple durations in the first list, a minimum value is taken to obtain a data transmission delay from the target ground station to the ground station.

According to the path verification method for satellite Internet provided by the present invention, according to the measurement packet sent by the target ground station, the direction of the access satellite orbit from the target ground station to the ground station is estimated, including:

According to the access satellite number of the source ground station in any measurement packet sent by the target ground station and the two-line orbit element information of all satellites in the constellation stored in advance, the access of the target ground station to the ground station is estimated Orbit direction of the satellite.

According to the path verification method for satellite Internet provided by the present invention, the statistical outlier analysis of the global delay gradient matrix includes:

Analyzing the global delay gradient matrix using a preset outlier detection algorithm to select outliers from the global delay gradient matrix that are greater than the safety threshold of the preset outlier detection algorithm;

The preset outlier detection algorithm includes but not limited to: IQR test method and Grubbs test method.

According to the path verification method for satellite Internet provided by the present invention, the shortest data transmission delay of the round-trip satellite-ground link is determined according to the orbital altitude of the satellite, and the measured value of the data transmission delay of the potential risk path is the element value corresponding to the ground station pair of the potential risk path in the global delay matrix;

The process of determining the theoretical estimated value of the data transmission delay of the potential risk path includes:

determining adjacent paths to said potentially risky path;

Extracting elements corresponding to the ground station pairs of the adjacent paths from the global delay matrix to form a reference delay matrix;

For the ground station pairs within the range of the reference delay matrix, determine the mapping relationship between the data transmission delay and the geographical distance through a regression analysis method;

According to the mapping relationship and the distance between the ground station pairs of the potential risk path, a theoretical estimated value of the data transmission delay of the potential risk path is determined.

According to the path verification method for satellite Internet provided by the present invention, the determination of the adjacent path of the potential risk path includes:

taking a path satisfying the second condition as an adjacent path of the potential risk path;

Wherein, the second condition is:

the distance between the source end and the source end of the potential risk path is less than a first threshold, and

The distance between the destination end and the destination end of the potential risk path is smaller than a second threshold.

In a second aspect, the present invention provides a path verification device for satellite Internet, the device comprising:

An inter-station distance matrix generation module is used to generate an inter-station distance matrix according to the geographic location information between ground stations;

The global delay matrix generation module is used to summarize the inter-station delay table of each ground station to obtain the global delay matrix;

A global delay gradient matrix generation module, configured to differentiate the corresponding elements of the global delay matrix and the inter-station distance matrix to obtain a global delay gradient matrix;

A potential risk path identification module, configured to perform statistical outlier analysis on the global delay gradient matrix, and use the data transmission path of the ground station pair with an outlier value as a potential risk path;

A risk path identification module, configured to identify the potential risk path as a risk path when the potential risk path satisfies the first condition;

Wherein, the data transmission delay from each target ground station to the ground station is stored in the inter-station delay table of each of the ground stations; the target ground station is a ground station other than the ground station;

The first condition is that the difference between the measured value of the data transmission delay and the theoretical estimated value is greater than the shortest data transmission delay of a round-trip satellite-ground link.

In a third aspect, the present invention provides an electronic device, including a memory, a processor, and a computer program stored on the memory and operable on the processor, when the processor executes the program, the first The path verification method for satellite Internet described in the aspect.

In a fourth aspect, the present invention provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the path verification method for satellite Internet as described in the first aspect is implemented.

The present invention provides a path verification method and device for satellite Internet, using the geographic location information between ground stations to construct an inter-station distance matrix, and using the measured data transmission delay between ground stations to construct a global delay matrix ; Differentiate the corresponding elements of the global delay matrix and the inter-station distance matrix to obtain the global delay gradient matrix; the global delay gradient matrix reflects the implicit relationship between the data transmission delay and the geographical distance between the ground stations The mapping relationship, from a global perspective, performs outlier detection on the global delay gradient matrix to initially screen risk paths; due to gradient anomalies, in addition to detours caused by path hijacking attacks, it may also come from local network congestion. In order to avoid misjudgment, and considering that for the path hijacking attack in the satellite Internet, an additional off-satellite and on-satellite operation is an undeniable attack feature, the risk criterion "potential risk path If the difference between the measured value of data transmission delay and the theoretical estimated value is greater than the shortest data transmission delay of a round-trip satellite-ground link, the potential risk path is a risk path", and the potential risk path is analyzed from a local perspective according to the risk criterion. Risk verification. The present invention replaces the encrypted tag matching verification method used in the hop-by-hop verification mechanism, avoids a large amount of signaling overhead and calculation overhead caused by frequent path changes under the dynamic topology of the satellite Internet, and improves the efficiency of path verification in the satellite Internet scene. performance.

Description of drawings

In order to more clearly illustrate the present invention or the technical solutions in the prior art, the accompanying drawings that need to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings in the following description are the present invention. For some embodiments of the invention, those skilled in the art can also obtain other drawings based on these drawings without creative effort.

FIG. 1 is a schematic diagram of path change caused by route hijacking provided by the prior art;

Fig. 2 is a schematic diagram of the update of the desired forwarding path caused by satellite-ground handover provided by the prior art;

Fig. 3 is a schematic flow chart of a path verification method for satellite Internet provided by the present invention;

Fig. 4 is a schematic diagram of IP packet header expansion provided by the present invention;

Fig. 5 is a schematic diagram of in-band delay measurement provided by the present invention;

Fig. 6 is a schematic diagram of preliminary screening through the global gradient matrix provided by the present invention;

Fig. 7 is a schematic diagram of extracting adjacent paths according to geographic location provided by the present invention;

Fig. 8 is a schematic diagram of extracting adjacent paths to construct a reference delay matrix provided by the present invention;

Fig. 9 is an example diagram of the whole process provided by the present invention;

Fig. 10 is a schematic structural diagram of a path verification device for satellite Internet provided by the present invention;

FIG. 11 is a schematic structural diagram of an electronic device implementing a path verification method for satellite Internet provided by the present invention;

Reference signs:

110: processor; 120: communication interface; 130: memory; 1140: communication bus.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention , but not all examples. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

The route verification method and device for satellite Internet of the present invention will be described below with reference to FIGS. 1-11 .

The present invention is applicable to the scenario of satellite Internet-based ground station switching and accessing satellites, and involves user end equipment, ground stations and satellite Internet. Among them, the user terminal accesses the satellite Internet through its nearby ground station, and the satellite nodes are deployed with inter-satellite links. Figure 1 is a schematic diagram of path changes caused by route hijacking in the satellite Internet scenario. As shown in Figure 1, the expected path for data transmission in the satellite Internet is R1→R2→R3→R10→R5→R6→R7; the attacker routes R10 Hijacking Route hijacking, deriving the off-star path from R10 to the ground station near the attacker and the up-star path from the ground station near the attacker to R10, that is, the data flow direction is R1→R2→R3→R10→attacker→R10 →R5→R6→R7, the attacker can copy the data flow and keep it unknown, which seriously damages the security of user data. For this reason, detecting route hijacking attacks is crucial for satellite Internet applications.

Path verification is one of the main means to detect route hijacking. Most of the existing path verification methods adopt the hop-by-hop verification mechanism. When the ground is switched, the path planning server switches the expected path of data transmission in the satellite Internet from R1→R2→R3→R4→R5→R6→R7 to R8→R9→R10→R5→R6→R7, according to the desired path R1→R2 → The shared key established by R3→R4→R5→R6→R7 and the encryption mark generated based on the shared key and embedded in the packet header are no longer applicable, and it is necessary to follow the expected path R8→R9→R10→R5→R6→R7 Establishing a new shared key and using the new shared key to recalculate the path node encryption mark and insert the packet header, this series of operations involves multiple signaling interactions and encryption and decryption calculations, resulting in a large amount of signaling and computing overhead.

Of course, in terms of path verification, there are some path verification methods that rely on the expected forwarding path but are not exactly the same as the hop-by-hop verification mechanism in the background technology, such as randomly selecting some satellite nodes in the expected path for verification, instead of verifying all satellite nodes in the expected path. Path verification methods for node verification, but these methods also face the above-mentioned technical defects. And the present invention makes improvement to above-mentioned technical defect.

In a first aspect, the present invention provides a path verification method for satellite Internet, as shown in Figure 3, the method includes:

S11. Generate an inter-station distance matrix according to the geographic location information between the ground stations;

S12. Summarize the inter-station delay table of each ground station to obtain a global delay matrix; wherein, the data transmission time from each target ground station to the ground station is stored in the inter-station delay table of each ground station extension; the target ground station is a ground station other than the ground station;

S13. Differentiate the corresponding elements of the global delay matrix and the inter-station distance matrix to obtain a global delay gradient matrix;

S14. Perform statistical outlier analysis on the global delay gradient matrix, and use the data transmission path of the ground station pair with the outlier value as a potential risk path;

S15. When the potential risk path satisfies the first condition, determine that the potential risk path is a risk path; wherein, the first condition is that the difference between the measured value of the data transmission delay and the theoretical estimated value is greater than one round-trip satellite The shortest data transmission delay of the ground link.

The present invention provides a path verification method for satellite Internet, which uses the geographic location information between ground stations to construct a distance matrix between stations, and uses the measured data transmission delay between ground stations to construct a global delay matrix; The global delay matrix and the corresponding elements of the inter-station distance matrix are differentiated to obtain the global delay gradient matrix; the global delay gradient matrix reflects the implicit mapping relationship between the data transmission delay between the ground stations and the geographical distance , from a global perspective, an outlier detection is performed on the global delay gradient matrix to initially screen risky paths; due to gradient anomalies, in addition to detours caused by path hijacking attacks, it may also come from local network congestion. In order to avoid misjudgment, and considering that for the path hijacking attack in the satellite Internet, an additional off-satellite and on-satellite operation is an undeniable attack feature, the risk criterion "potential risk path If the difference between the measured value of data transmission delay and the theoretical estimated value is greater than the shortest data transmission delay of a round-trip satellite-ground link, the potential risk path is a risk path", and the potential risk path is analyzed from a local perspective according to the risk criterion. Risk verification. The present invention replaces the encrypted tag matching verification method used in the hop-by-hop verification mechanism, avoids a large amount of signaling overhead and calculation overhead caused by frequent path changes under the dynamic topology of the satellite Internet, and improves the efficiency of path verification in the satellite Internet scene. performance.

Specifically, the present invention uses a processing center as the execution subject, and the processing center is a device with computing capability, which may be a certain ground station or a specialized computing center. The processing center maintains the geographic location information of all ground stations in the constellation and the constellation feature information (satellite orbit height), so for the above S11, the distance between the ground stations can be calculated according to the geographic location information between the ground stations , to construct the inter-station distance matrix;

Further, the i-th row and the j-th column element in the inter-station distance matrix represent the inter-station distance between the i-th ground station and the j-th ground station in the constellation.

Specifically, in S12, the inter-station delay table of each ground station is used to store the data transmission delay from any ground station in the constellation to the local ground station. The processing center will request all ground stations to obtain their inter-station delay tables, and use the data transmission delay from the source ground station to the destination ground station as the elements of the global delay matrix to construct a global delay matrix. That is, the i-th row and the j-th column element in the global delay matrix represent the data transmission delay from the i-th ground station to the j-th ground station in the constellation.

The invention expands the packet header in the band to form a time delay measurement package, and accurately determines the data transmission time delay between the ground stations through the time interval between sending and receiving of the time delay measurement package between the ground stations.

That is, the generation process of the inter-station delay table of each said ground station is as follows:

Make the ground station locally create 4 inter-station delay sub-tables with the source ground station number and data transmission time delay as fields; The four access satellite orbit directions involved in the station disembarkation correspond respectively, and the four access satellite orbit directions are respectively the north direction of the upper satellite and the south direction of the lower satellite, the north direction of the upper satellite and the north direction of the lower satellite, the south direction of the upper satellite and the lower direction of the satellite. The star is north and the upper star is south and the lower star is south;

In a measurement cycle, control each of the target ground stations to send a delay measurement packet to the ground station at intervals of a preset duration; wherein, the delay measurement packet is to embed the header of the IP data packet into the source ground Station number (SourceGS ID), source ground station access satellite number (Up SatID) and sending time stamp (Send Time);

The setting of this step makes it possible for each ground station to send n delay measurement packets to other ground stations continuously in one measurement cycle, avoiding the time-consuming data transmission between ground stations caused by only sending one delay measurement packet. The problem of inaccurate delay measurement.

Fig. 4 is a schematic diagram of IP packet header expansion. The present invention adopts a one-way measurement method based on sending time stamps, which avoids dependence on transport layer protocols and uncertainty in terminal processing.

making the ground station estimate the data transmission delay and access satellite orbit direction from each of the target ground stations to the ground station according to the delay measurement packet sent by each of the target ground stations;

It should be noted that the ground station may receive delay measurement packets from multiple target ground stations within the measurement period. Before this step, the ground station will record the receiving time and analyze the packet header after receiving each analytical delay measurement packet; then it will classify the delay measurement packet according to the source ground station number in the packet header, and obtain each target Delay measurement packets sent by the ground station.

In this step, according to the measurement packet sent by the target ground station, the data transmission delay from the target ground station to the ground station is estimated, specifically including:

List the duration between the sending time stamp and the receiving time of each measurement packet sent by the target ground station in the first list;

After filtering the multiple durations in the first list, a minimum value is taken to obtain a data transmission delay from the target ground station to the ground station.

Here, the purpose of filtering the multiple durations in the first list is to remove measurement glitches.

According to the measurement packet sent by the target ground station, estimating the access satellite orbit direction from the target ground station to the ground station, including:

According to the access satellite number of the source ground station in any measurement packet sent by the target ground station and the two-line orbit element information of all satellites in the constellation stored in advance, the access of the target ground station to the ground station is estimated Orbit direction of the satellite. Each ground station maintains the TLE (two-row orbit element) information of all satellites in the constellation;

It should be noted that the first line in the TLE information includes: line number (1), satellite number, security level, launch year and international launch number, TLE duration (the TLE data release time year and the current year day), the first-order time derivative of the average motion, the second-order time derivative of the average motion, the BSTAR drag modulation coefficient, the ephemeris type, the ephemeris number and the checksum; the second line in the TLE information includes: line number ( 2), satellite number, angle between orbital plane and equatorial plane, right ascension of ascending node, orbital eccentricity, argument of perigee, mean anomaly, average motion (number of circles around the earth per day), number of circles in orbit and calibration and

The position of the satellite at any time can be calculated according to the TLE (two-line orbit element) information of the satellite. Therefore, according to the access satellite number of the source ground station in any measurement packet sent by the target ground station and the two lines of orbit element information of all satellites in the constellation pre-stored, the running direction of the access satellite can be estimated, which is equivalent to The access satellite orbit direction from the target ground station to the ground station is determined, so as to locate the corresponding inter-station delay sub-table,

Using the number of each target ground station as an index, insert the data transmission delay from each target ground station to the ground station into the access satellite orbit direction from each target ground station to the ground station In the corresponding inter-station delay sub-table, get 4 inter-station delay sub-tables filled with data;

The four inter-station delay sub-tables of the filled data are combined to obtain the inter-station delay table of the ground station.

It should be noted that, by default, the present invention always uses the path with the shortest delay between the two ground stations to transmit the data flow, so the data transmission delay between the two ground stations corresponds to the path with the shortest delay .

Fig. 5 is a schematic diagram of in-band delay measurement corresponding to the above-mentioned generation process of the inter-station delay table of the ground station.

Specifically, in the above S13, the element values in the global delay gradient matrix reflect the relationship between the data transmission delay between the two ground stations as a function of the distance.

That is, the element value of the i-th row and the j-th column in the global delay gradient matrix reflects the data transmission delay from the i-th ground station to the j-th ground station in the constellation and the difference between the i-th ground station and the j-th ground station in the constellation The mapping relationship of the distance.

In the dynamic network, the expected forwarding path (the expected path node sequence) is time-varying, and is no longer suitable as a standard for path verification. The present invention uses the mapping relationship between data transmission delay and geographical distance as a new verification comparison, and through the specific access satellite Decoupling eliminates the need for recalculation of path verification standards caused by satellite-to-ground switching, and avoids a large amount of overhead caused by recalculation.

Specifically, in the S14, performing statistical outlier analysis on the global delay gradient matrix, including:

Analyzing the global delay gradient matrix using a preset outlier detection algorithm to select outliers from the global delay gradient matrix that are greater than the safety threshold of the preset outlier detection algorithm;

The preset outlier detection algorithm includes but not limited to: IQR test method and Grubbs test method.

In the present invention, the implicit mapping relationship between the data transmission delay and the geographical distance of the ground station pair (that is, the source ground station-destination ground station) is used as the comparative quantity in the satellite Internet path verification, and two stages from global to local are carried out. Path verification, thereby improving the performance of path verification in satellite Internet scenarios. S14 is an operation step of the global verification stage (preliminary screening stage).

Figure 6 is a schematic diagram of preliminary screening through the global gradient matrix. As shown in Figure 6, based on the assumption that attackers cannot invade most nodes of the satellite Internet, most elements in the global delay gradient matrix should satisfy similar delay and Therefore, the statistical outlier analysis is performed on the global delay gradient matrix to screen the ground station pairs (GS-GS) with gradient anomalies from a global perspective, and the ground station pairs (GS-GS) with gradient anomalies The data transmission path as a potential risk path;

It should be noted that the safety threshold in the outlier detection algorithm is usually given based on experience.

Specifically, S15 is a local verification stage, and the gradient anomaly of the ground station pair may also come from local network congestion in addition to the detour caused by the path hijacking attack. For path hijacking attacks in the satellite Internet, an additional off-satellite and on-satellite operation is an undeniable attack feature, so the difference between the actual measured value and the theoretical estimated value of the data transmission delay according to the risk path of the present invention is greater than The undeniable physical constraint of RTT (the shortest data transmission delay for a round-trip satellite-ground link) of the satellite-ground link establishes a verification criterion for verifying whether a potential risk path is a risk path: data transmission delay of a potential risk path If the difference between the measured value and the theoretical estimated value is greater than the shortest data transmission delay of a round-trip satellite-ground link, the potential risk path is identified as a risk path; and then the risk verification of the potential risk path is completed from a local perspective.

Here, the shortest data transmission delay for a round-trip satellite-ground link is determined according to the orbital height of the satellite. In a constellation, the present invention defaults that the satellites are deployed on the same floor and have the same orbital height.

The actual measured value of the data transmission delay of the potential risk path is the element value corresponding to the ground station pair of the potential risk path in the aforementioned global delay matrix;

The process of determining theoretical estimates of data transmission delays for potentially risky paths, including:

determining adjacent paths to said potentially risky path;

That is: according to the set reference distance and the geographical locations of the source ground station and the destination ground station of the potential risk path, the adjacent paths of the potential risk path are screened out. Fig. 7 is a schematic diagram of extracting adjacent paths according to geographic location. As shown in Fig. 7, determining the adjacent paths of potential risk paths specifically includes:

taking a path satisfying the second condition as an adjacent path of the potential risk path;

Wherein, the second condition is:

the distance between the source end and the source end of the potential risk path is less than a first threshold, and

The distance between the destination end and the destination end of the potential risk path is smaller than a second threshold.

It should be noted that the first threshold and the second threshold are determined based on experience. Potential risk paths and their adjacent paths are likely to be in a similar congested environment.

Extracting elements corresponding to the ground station pairs of the adjacent paths from the global delay matrix to form a reference delay matrix;

FIG. 8 is a schematic diagram of extracting adjacent paths to construct a reference delay matrix. The clustering characteristics of the reference delay matrix can reflect the congestion near potential risk paths.

For the ground station pairs within the range of the reference delay matrix, determine the mapping relationship between the data transmission delay and the geographical distance through a regression analysis method;

Taking the ground station pairs of the adjacent paths of the potential risk path as reference, the mapping relationship between the data transmission delay and the geographical distance in the vicinity of the potential risk path is modeled by regression analysis method.

According to the mapping relationship and the distance between the ground station pairs of the potential risk path, a theoretical estimated value of the data transmission delay of the potential risk path is determined.

The theoretical estimated value of the potential risk path is estimated by using the mapping relationship, so as to exclude the influence of the network congestion near the potential risk path on the potential risk path in the above verification criterion.

To sum up, the present invention realizes path verification through collaborative control of in-band measurement and out-of-band processing, as shown in the example diagram of the whole process shown in Figure 9, in which ground station is a simultaneous term for ground station, and in-band measurement mainly refers to expanding the header in the ground station Form a delay measurement package and send and receive delay measurement packages between ground stations to determine the data transmission delay between ground stations; out-of-band processing mainly refers to two-stage path verification from global to local. This method does not require any modifications to satellite node hardware and routing protocols, and improves the deployability of path verification in the real environment of incremental launch of giant constellation nodes.

In addition, in order to increase the information stored and maintained by the existing ground stations in the present invention, it is necessary to add a time delay table for storing time delay information between ground stations.

In the second aspect, the path verification device for satellite Internet provided by the present invention is described. The path verification device for satellite Internet described below and the path verification method for satellite Internet described above can be referred to in correspondence. Figure 10 illustrates a schematic structural diagram of a path verification device for satellite Internet, as shown in Figure 10, the device includes:

Inter-station distance matrix generation module 21, for generating inter-station distance matrix according to the geographic location information between ground stations;

The global delay matrix generation module 22 is used to summarize the inter-station delay table of each ground station to obtain the global delay matrix;

The global delay gradient matrix generation module 23 is used to differentiate the corresponding elements of the global delay matrix and the inter-station distance matrix to obtain a global delay gradient matrix;

A potential risk path identification module 24, configured to perform statistical outlier analysis on the global delay gradient matrix, and use the data transmission path of the ground station pair with an outlier as a potential risk path;

A risk path identification module 25, configured to identify the potential risk path as a risk path when the potential risk path satisfies the first condition;

Wherein, the data transmission delay from each target ground station to the ground station is stored in the inter-station delay table of each of the ground stations; the target ground station is a ground station other than the ground station;

The first condition is that the difference between the measured value of the data transmission delay and the theoretical estimated value is greater than the shortest data transmission delay of a round-trip satellite-ground link.

A path verification device for satellite Internet provided by the present invention uses geographical location information between ground stations to construct an inter-station distance matrix, and utilizes measured data transmission delays between ground stations to construct a global delay matrix; The global delay matrix and the corresponding elements of the inter-station distance matrix are differentiated to obtain the global delay gradient matrix; the global delay gradient matrix reflects the implicit mapping relationship between the data transmission delay between the ground stations and the geographical distance , from a global perspective, an outlier detection is performed on the global delay gradient matrix to initially screen risky paths; due to gradient anomalies, in addition to detours caused by path hijacking attacks, it may also come from local network congestion. In order to avoid misjudgment, and considering that for the path hijacking attack in the satellite Internet, an additional off-satellite and on-satellite operation is an undeniable attack feature, the risk criterion "potential risk path If the difference between the measured value of data transmission delay and the theoretical estimated value is greater than the shortest data transmission delay of a round-trip satellite-ground link, the potential risk path is a risk path", and the potential risk path is analyzed from a local perspective according to the risk criterion. Risk verification. The present invention replaces the encrypted tag matching verification method used in the hop-by-hop verification mechanism, avoids a large amount of signaling overhead and calculation overhead caused by frequent path changes under the dynamic topology of the satellite Internet, and improves the efficiency of path verification in the satellite Internet scene. performance. On the basis of the above embodiments, as an optional embodiment, the device further includes: a generating module for generating an inter-station delay table of the ground station;

The generating module specifically includes:

The inter-station delay sub-table construction unit is used to make the ground station locally create 4 inter-station delay sub-tables with the source ground station number and data transmission delay as fields; wherein, the 4 inter-station delay sub-tables The table corresponds to the four access satellite orbit directions respectively, and the four access satellite orbit directions are respectively the upper star north and the lower star south, the upper star north and the lower star north, the upper star south and the lower star north, and the upper star north and the lower star north. The star is south and the lower star is south;

The delay measurement packet sending unit is used to control each of the target ground stations to send a delay measurement packet to the ground station at intervals of a preset duration within a measurement period; wherein, the delay measurement packet is for The IP data packet is obtained by embedding the source ground station number, the source ground station access satellite number and the packet header of the sending time stamp;

The data transmission delay and access satellite orbit direction determination unit is used to make the ground station estimate the data from each of the target ground stations to the ground station according to the delay measurement package sent by each of the target ground stations Transmission delay and access satellite orbit direction;

The data filling unit is used to insert the data transmission delay from each target ground station to the ground station into each target ground station to the ground station by using the number of each target ground station as an index In the inter-station delay sub-table corresponding to the access satellite orbit direction, 4 inter-station delay sub-tables filled with data are obtained;

A combining unit, configured to combine the four inter-station delay sub-tables of the filled data to obtain the inter-station delay table of the ground station.

On the basis of the above embodiments, as an optional embodiment, the data transmission delay and access satellite orbit direction determination unit includes: a data transmission delay determination sub-module and an access satellite orbit direction determination sub-module module;

The data transmission delay determination submodule is used for:

List the duration between the sending time stamp and the receiving time of each measurement packet sent by the target ground station in the first list;

After filtering the multiple durations in the first list, a minimum value is taken to obtain a data transmission delay from the target ground station to the ground station.

On the basis of the above embodiments, as an optional embodiment, the access satellite orbit direction determination submodule is used for:

According to the access satellite number of the source ground station in any measurement packet sent by the target ground station and the two-line orbit element information of all satellites in the constellation stored in advance, the access of the target ground station to the ground station is estimated Orbit direction of the satellite.

On the basis of the above embodiments, as an optional embodiment, the potential risk path identification module is specifically used for:

Analyzing the global delay gradient matrix using a preset outlier detection algorithm to select outliers from the global delay gradient matrix that are greater than the safety threshold of the preset outlier detection algorithm;

The preset outlier detection algorithm includes but not limited to: IQR test method and Grubbs test method.

On the basis of the above-mentioned embodiments, as an optional embodiment, the shortest data transmission delay of the round-trip satellite-ground link is determined according to the orbital height of the satellite;

The measured value of the data transmission delay of the potential risk path is an element value corresponding to the ground station pair of the potential risk path in the global delay matrix;

The risk path verification module, including for

The determination process includes: a determination unit for determining a theoretical estimated value of the data transmission delay of the potential risk path;

The determination unit includes:

a first determining subunit, configured to determine adjacent paths of the potential risk path;

The reference delay matrix construction subunit is used to extract elements corresponding to the ground station pairs of the adjacent paths from the global delay matrix to form a reference delay matrix;

The regression analysis subunit is used to determine the mapping relationship between the data transmission delay and the geographical distance through a regression analysis method for the ground station pairs within the range of the reference delay matrix;

The theoretical estimated value calculation subunit is configured to determine a theoretical estimated value of the data transmission delay of the potential risk path according to the mapping relationship and the inter-station distance of the pair of ground stations of the potential risk path.

On the basis of the foregoing embodiments, as an optional embodiment, the first determination subunit is specifically configured to:

taking a path satisfying the second condition as an adjacent path of the potential risk path;

Wherein, the second condition is:

the distance between the source end and the source end of the potential risk path is less than a first threshold, and

The distance between the destination end and the destination end of the potential risk path is smaller than a second threshold.

In the third aspect, FIG. 11 illustrates a schematic diagram of the physical structure of an electronic device. As shown in FIG. A communication bus 1140 , wherein the processor 1110 , the communication interface 1120 , and the memory 1130 communicate with each other through the communication bus 1140 . The processor 1110 can call the logic instructions in the memory 1130 to execute the path verification method for satellite Internet, the method includes: generating an inter-station distance matrix according to the geographic location information between ground stations; summarizing the inter-station distance matrix of each ground station A time delay table to obtain a global time delay matrix; differentiate the corresponding elements of the global time delay matrix and the inter-station distance matrix to obtain a global time delay gradient matrix; perform statistical outliers on the global time delay gradient matrix Analyze, and use the data transmission path of the pair of ground stations with abnormal values as a potential risk path; when the potential risk path satisfies the first condition, determine that the potential risk path is a risk path; wherein, each of the ground stations The inter-station delay table stores the data transmission delay from each target ground station to the ground station; the target ground station is a ground station other than the ground station; the first condition is when data transmission The difference between the measured value of the delay and the theoretical estimated value is greater than the shortest data transmission delay of a round-trip satellite-ground link.

In addition, the above-mentioned logic instructions in the memory 1130 may be implemented in the form of software function units and may be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program codes. .

In a fourth aspect, the present invention also provides a computer program product, the computer program product includes a computer program, the computer program can be stored on a non-transitory computer-readable storage medium, and when the computer program is executed by a processor, the computer can Execute the path verification method for satellite Internet provided by the above methods, the method includes: generating an inter-station distance matrix according to the geographic location information between ground stations; summarizing the inter-station delay table of each ground station to obtain the global time Delay matrix; differentiate the corresponding elements of the global delay matrix and the inter-station distance matrix to obtain a global delay gradient matrix; perform statistical outlier analysis on the global delay gradient matrix, and will have an outlier The data transmission path of the ground station pair is used as a potential risk path; when the potential risk path satisfies the first condition, the potential risk path is determined to be a risk path; wherein, in the inter-station delay table of each of the ground stations Store the data transmission delay from each target ground station to the ground station; the target ground station is a ground station other than the ground station; the first condition is the measured value and theoretical estimation of the data transmission delay The difference in value is greater than the shortest data transmission delay for a round-trip satellite-ground link.

In the fifth aspect, the present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it is implemented to perform the path verification method for satellite Internet provided by the above-mentioned methods , the method includes: generating an inter-station distance matrix according to geographical location information between ground stations; summarizing the inter-station delay table of each ground station to obtain a global delay matrix; combining the global delay matrix with the inter-station The corresponding elements of the distance matrix are differentiated to obtain the global delay gradient matrix; the statistical outlier analysis is performed on the global delay gradient matrix, and the data transmission path of the ground station pair with the outlier value is used as a potential risk path; When the potential risk path satisfies the first condition, the potential risk path is determined to be a risk path; wherein, the data transmission time from each target ground station to the ground station is stored in the inter-station delay table of each ground station delay; the target ground station is a ground station other than the ground station; the first condition is that the difference between the measured value of the data transmission time delay and the theoretical estimated value is greater than the shortest data transmission of a round-trip satellite-ground link delay.

The device embodiments described above are only illustrative, and the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in One place, or it can be distributed to multiple network elements. Part or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. It can be understood and implemented by those skilled in the art without any creative efforts.

Through the above description of the implementations, those skilled in the art can clearly understand that each implementation can be implemented by means of software plus a necessary general-purpose hardware platform, and of course also by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the prior art can be embodied in the form of software products, and the computer software products can be stored in computer-readable storage media, such as ROM/RAM, magnetic discs, optical discs, etc., including several instructions to make a computer device (which may be a personal computer, server, or network device, etc.) execute the methods described in various embodiments or some parts of the embodiments.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (10)

1. A path verification method for satellite Internet, characterized in that, the method comprises: Generate an inter-station distance matrix according to the geographic location information between ground stations; Summarize the inter-station delay table of each ground station to obtain the global delay matrix; Differentiating corresponding elements of the global delay matrix and the inter-station distance matrix to obtain a global delay gradient matrix; Performing statistical outlier analysis on the global delay gradient matrix, and using the data transmission path of the ground station pair with the outlier as a potential risk path; When the potential risk path satisfies the first condition, determining the potential risk path as a risk path; Wherein, the data transmission delay from each target ground station to the ground station is stored in the inter-station delay table of each of the ground stations; the target ground station is a ground station other than the ground station; The first condition is that the difference between the measured value of the data transmission delay and the theoretical estimated value is greater than the shortest data transmission delay of a round-trip satellite-ground link. 2. The path verification method for satellite Internet according to claim 1, wherein the generation process of the inter-station delay table of the ground station comprises: Make the ground station locally create 4 inter-station delay sub-tables with the source ground station number and data transmission delay as fields; wherein, the 4 inter-station delay sub-tables and the 4 access satellite orbit directions are respectively Correspondingly, the four kinds of orbit directions of the access satellites are respectively the upper satellite north direction and the lower satellite direction south, the upper satellite direction north and the lower satellite direction north, the upper satellite south direction and the lower satellite north direction, and the upper satellite south direction and the lower satellite direction south; In a measurement cycle, control each of the target ground stations to send a delay measurement packet to the ground station at intervals of a preset duration; wherein, the delay measurement packet is to carry out the source end ground station number of the IP data packet , The access satellite number of the source ground station and the packet header embedding of the sending time stamp are obtained; making the ground station estimate the data transmission delay and access satellite orbit direction from each of the target ground stations to the ground station according to the delay measurement packet sent by each of the target ground stations; Using the number of each target ground station as an index, insert the data transmission delay from each target ground station to the ground station into the access satellite orbit direction from each target ground station to the ground station In the corresponding inter-station delay sub-table, get 4 inter-station delay sub-tables filled with data; The four inter-station delay sub-tables of the filled data are combined to obtain the inter-station delay table of the ground station. 3. The path verification method for satellite Internet according to claim 2, wherein, according to the measurement packet sent by the target ground station, the data transmission time delay from the target ground station to the ground station is estimated, include: List the duration between the sending time stamp and the receiving time of each measurement packet sent by the target ground station in the first list; After filtering the multiple durations in the first list, a minimum value is taken to obtain a data transmission delay from the target ground station to the ground station. 4. The path verification method for satellite Internet according to claim 3, characterized in that, according to the measurement packet sent by the target ground station, the access satellite orbit direction from the target ground station to the ground station is estimated ,include: According to the access satellite number of the source ground station in any measurement packet sent by the target ground station and the two-line orbit element information of all satellites in the constellation stored in advance, the access of the target ground station to the ground station is estimated Orbit direction of the satellite. 5. The path verification method for satellite Internet according to any one of claims 1 to 4, wherein said performing statistical outlier analysis on said global delay gradient matrix includes: Analyzing the global delay gradient matrix using a preset outlier detection algorithm to select outliers from the global delay gradient matrix that are greater than the safety threshold of the preset outlier detection algorithm; The preset outlier detection algorithm includes but not limited to: IQR test method and Grubbs test method. 6. The path verification method for satellite Internet according to any one of claims 1 to 4, wherein the shortest data transmission time delay of the round-trip satellite-ground link is determined according to the orbital height of the satellite, The measured value of the data transmission delay of the potential risk path is an element value corresponding to the ground station pair of the potential risk path in the global delay matrix; The process of determining the theoretical estimated value of the data transmission delay of the potential risk path includes: determining adjacent paths to said potentially risky path; Extracting elements corresponding to the ground station pairs of the adjacent paths from the global delay matrix to form a reference delay matrix; For the ground station pairs within the range of the reference delay matrix, determine the mapping relationship between the data transmission delay and the geographical distance through a regression analysis method; According to the mapping relationship and the distance between the ground station pairs of the potential risk path, a theoretical estimated value of the data transmission delay of the potential risk path is determined. 7. The path verification method for satellite Internet according to claim 6, wherein said determining the adjacent path of said potential risk path comprises: taking a path satisfying the second condition as an adjacent path of the potential risk path; Wherein, the second condition is: the distance between the source end and the source end of the potential risk path is less than a first threshold, and The distance between the destination end and the destination end of the potential risk path is smaller than a second threshold. 8. A path verification device for satellite Internet, characterized in that the device comprises: An inter-station distance matrix generation module is used to generate an inter-station distance matrix according to the geographic location information between ground stations; The global delay matrix generation module is used to summarize the inter-station delay table of each ground station to obtain the global delay matrix; A global delay gradient matrix generation module, configured to differentiate the corresponding elements of the global delay matrix and the inter-station distance matrix to obtain a global delay gradient matrix; A potential risk path identification module, configured to perform statistical outlier analysis on the global delay gradient matrix, and use the data transmission path of the ground station pair with an outlier value as a potential risk path; A risk path identification module, configured to identify the potential risk path as a risk path when the potential risk path satisfies the first condition; Wherein, the data transmission delay from each target ground station to the ground station is stored in the inter-station delay table of each of the ground stations; the target ground station is a ground station other than the ground station; The first condition is that the difference between the measured value of the data transmission delay and the theoretical estimated value is greater than the shortest data transmission delay of a round-trip satellite-ground link. 9. An electronic device comprising a memory, a processor, and a computer program stored on the memory and operable on the processor, wherein the processor according to claim 1 is implemented when executing the program. The path verification method for satellite Internet described in any one of to 7. 10. A non-transitory computer-readable storage medium, on which a computer program is stored, characterized in that, when the computer program is executed by a processor, it realizes the satellite Internet as described in any one of claims 1 to 7. Path validation method.

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