KR102054715B1 - Physical layer security method and system for cooperative multihop routing in ad-hoc wireless network - Google Patents

Abstract

A physical layer security method and system for cooperative multihop routing in an ad-hoc wireless network are presented. According to an embodiment of the present invention, the physical layer security method for cooperative multihop routing in an ad-hoc wireless network comprises the steps of: transmitting information at a transmitter in an ad-hoc wireless network environment where an eavesdropper is present; receiving the transmitted information through at least one of a plurality of relays of a plurality of hops, and transmitting the received information to a receiver; and receiving information from the receiver through the relay. In the step of receiving the information through the at least one of the plurality of relays of the plurality of hops and transmitting to the receiver, at least one relay may be selected from each relay cluster of the plurality of hops to transmit the information.

Description

PHYSICAL LAYER SECURITY METHOD AND SYSTEM FOR COOPERATIVE MULTIHOP ROUTING IN AD-HOC WIRELESS NETWORK}

The following embodiments are directed to a physical layer security method and system for collaborative multihop routing in an ad-hoc wireless network.

As an alternative to traditional cryptographic techniques for wireless network security, information theoretical secret-based physical layer (PHY) security has recently emerged.

In the past, various routing protocols have been proposed based on point-to-point error free links for wireless multihop links. However, these protocols are not modeled with the probabilistic behavior and broadcasting characteristics of wireless channels in mind. To overcome this limitation, we can investigate channel-aware routing strategies and consider the possibility of routing outages as a performance indicator. In particular, a routing strategy for a multi-hop network consisting of a plurality of relays at each hop can be provided to achieve diversity gains provided by cooperation between relays. Cooperative networks are quite popular with the diversity benefits provided by them. However, none of these tasks considered analysis in PHY security. With increasing consensus on protecting wireless networks with unconditional security based on information-theoretical constraints, many research works today consider physical layer security an essential criterion for investigation.

Existing cryptographic approaches are based on the difficulty of certain mathematical functions, such as discrete algebra problems resulting in large numbers of prime factors and conditional security. Unlike the cryptographic approach, physical layer security is another paradigm for achieving theoretically complete confidentiality by taking advantage of the uncertainty of the radio channel, such as interference, noise, and time-varying characteristics of the fading channel. Moreover, proper channel coding schemes and signal processing schemes enable the transmission of confidential messages without the need for a secret key. For complete secrecy, for every secret message X and the observer's observation Y for the secret message, Pr (XIY) = Pr (X) when defining the probability Pr. Existing studies have shown that perfect confidentiality is possible because secret messages can be transmitted at positive rates when the eavesdropper degrades the eavesdropping channel. Although the eavesdropping channel has better average signal to noise ratio (SNR) than the main channel, the presence of complete secrecy has been seen under the fading channel.

Representative methods for improving physical layer security include the use of several diversity techniques such as Multiple Input Multiple Output (MIMO), multi-user diversity, and collaborative diversity. Most of these tasks consist of a relay network creating a two-hop relay system and a small network of single transmitters, single or multiple legitimate receivers and eavesdroppers. Using game theory and probabilistic geometry, some work has been done in multi-hop networks with information security constraints. A multihop system capable of physical layer security is proposed by supporting a single decode and forward (DF) relay on each hop.

Royer E M, Toh C K. A review of current routing protocols for ad hoc mobile wireless networks [J]. IEEE Personal Communications, 1999, 6 (2): 46-55.

Embodiments describe a physical layer security method and system for cooperative multihop routing in an ad-hoc wireless network, and more specifically, provide a physical layer security method in connection with a routing scheme in a multi-hop wireless network. To provide technology.

In the ad-hoc wireless network environment where an eavesdropper exists, multiple relays are installed on each hop to select an optimal relay between hops, thereby applying a secure routing technique between transceivers to provide a confidential message. A physical layer security method and system for cooperative multihop routing in an ad-hoc wireless network capable of transmitting a message) is provided.

According to an embodiment, a physical layer security method for cooperative multihop routing in an ad-hoc wireless network may include transmitting information from a transmitter in an ad-hoc wireless network environment in which an eavesdropper exists; Receiving the transmitted information through at least one or more of a plurality of relays of a plurality of hops, and transmitting the received information to a receiver; And receiving information through the relay at the receiver, and receiving the information through at least one or more of the plurality of relays of the plurality of hops, and transmitting the information to the receiver, includes: each relay of the plurality of hops At least one relay in the cluster may be selected to transmit the information.

Receiving the information through at least one or more of a plurality of relays of a plurality of hops, and transmitting to the receiver, each hop in each relay cluster based on the instantaneous channel conditions of the receiver and the eavesdropper at each hop -by-hop The optimal security relay can be selected to apply a secure routing scheme to send confidential messages.

The relay is a decode and forward (DF) relay and decodes and re-encodes the signal received digitally at the preceding node prior to retransmission through a wireless fading channel called the main channel to prevent eavesdropping. can do.

Receiving the information through at least one or more of a plurality of relays of a plurality of hops, and transmitting to the receiver, the signal to noise ratio (SNR) of the main channel at each hop and the eavesdropper channel Deriving a secrecy capacity probability by subtracting the instantaneous capacity of the eavesdropping channel from the instantaneous capacity of the main channel based on the instantaneous signal-to-noise ratio (SNR).

Receiving the information through at least one or more of a plurality of relays of a plurality of hops, and transmitting to the receiver, comprising: calculating a cumulative distribution function (CDF) of the confidentiality signal to noise ratio (SNR) in each hop; And selecting a relay having the maximum confidentiality signal to noise ratio (SNR) at each hop.

Receiving the information through at least one or more of a plurality of relays of a plurality of hops and passing it to a receiver may be provided below a threshold confidentiality rate Rs given a instantaneous end-to-end transmission rate to quantify the confidentiality performance. Probability of secrecy outage, which is the probability of falling, can be derived.

를 정의하는 단계;

및

로 초기화하는 단계; 각각의 홉 k = 1, ... , K-2에서 선택된 최대 보안유지 릴레이를 구하는 단계; 홉 K-1에서, 가장 큰

을 경로로 선택하는 대신

로 조인트 릴레이를 선택하는 단계; 및 최적의 비밀유지 릴레이 {

}를 결정하는 단계를 포함할 수 있다. Receiving the information through at least one or more of a plurality of relays of a plurality of hops and delivering the information to a receiver includes performing a secure multihop routing policy using an algorithm, and secured using the algorithm. Performing a multihop routing policy may include setting the number of hops and the number of relay cluster relays; Index of the selected relay node on each hop

Defining;

And

Initializing to; Obtaining a maximum security relay selected at each hop k = 1, ..., K-2; In hop K-1, the largest

Instead of choosing

Selecting a furnace joint relay; And optimal confidentiality relays {

} May be determined.

According to another embodiment, a physical layer security system for cooperative multihop routing in an ad-hoc wireless network includes a transmitter for transmitting information in an ad-hoc wireless network environment in which an eavesdropper exists; An intermediate cluster that receives the transmitted information through at least one or more of a plurality of relays of a plurality of hops and delivers the information to a receiver; And a receiver receiving information through the relay, wherein the intermediate cluster may select at least one relay from each relay cluster of a plurality of hops to transmit the information.

According to embodiments, in an ad-hoc wireless network environment where an eavesdropper exists, a plurality of relays are installed on each hop to select an optimal relay between hops, thereby applying a secure routing technique between transceivers to provide a confidential message. It is possible to provide a physical layer security method and system for cooperative multihop routing in an ad-hoc wireless network capable of transmitting a (confidential message).

1 is a diagram for describing keyless physical layer (PHY) secure transmission according to an embodiment.
2 is a view for explaining a confidential capacity according to an embodiment.
3 is a flowchart illustrating a physical layer security method for cooperative multihop routing in an ad-hoc wireless network according to an embodiment.
4 is a diagram schematically illustrating a physical layer security system for cooperative multihop routing in an ad-hoc wireless network according to an embodiment.
5A illustrates a result of comparing a non-zero secrecy capacity probability and an average main channel signal to noise ratio (SNR) according to an embodiment.
5B illustrates a result of comparing the confidentiality probability and the average main channel signal to noise ratio (SNR) according to an embodiment.
6A illustrates a result of comparing the confidentiality outage probability and the average main channel signal to noise ratio (SNR) according to an embodiment.
6B illustrates a confidentiality outage probability according to the threshold secrecy rate Rs according to one embodiment.

Hereinafter, exemplary embodiments will be described with reference to the accompanying drawings. However, the described embodiments may be modified in many different forms, and the scope of the present invention is not limited to the embodiments described below. In addition, various embodiments are provided to more fully describe the present invention to those skilled in the art. Shape and size of the elements in the drawings may be exaggerated for more clear description.

The following embodiments focus on the problem of combining routing policy and physical layer security in a multihop wireless network with cooperative diversity. Consider a system consisting of a single transmitter and receiver connected through a series of intermediate clusters of multiple (multiple) decode and forward (DF) relays and eavesdroppers.

Here, hop-by-hop optimal security relays can be selected in each cluster to achieve full diversity based on the instantaneous channel conditions of the receiver and eavesdropper on each hop. Signal processing techniques focus on signal processing rather than channel coding because they help to reduce the complexity of channel coding, especially in system models that use diversity to account for the degree of free space.

As a major technology, ad hoc routing architectures and algorithms can be proposed in collaborative wireless networks, and the main results can be derived from secrecy outage probability and secrecy capacity probability.

1 is a diagram for describing keyless physical layer (PHY) secure transmission according to an embodiment.

Referring to FIG. 1, one embodiment may provide a physical layer security method and system associated with a routing scheme in a multi-hop wireless network, and in particular, by applying a cooperative routing scheme, maximum diversity between hops may be obtained. full diversity) effect can be achieved.

In one embodiment, in the ad-hoc wireless network environment where an eavesdropper 120 exists, a plurality of relays 110 and 130 are installed on each hop to select an optimal relay between hops so that the transmitter 101 and the receiver can be selected. A secure routing scheme between the 103 may be applied to transmit a confidential message through the channel 120. At this time, the optimal relay may be selected in consideration of the real-time channel state of the eavesdropper 120 and the relays 110 and 130.

Confidential messages may be sent using channel coding schemes that cause significant confusion to eavesdropper 120 while maintaining reliable decoding to the other party. As a result, a channel code with a low probability of error and a high entropy can be designed. In addition, the physical layer characteristics of the wireless channel such as multipath fading, interference, and noise may be utilized.

2 is a view for explaining a confidential capacity according to an embodiment.

Referring to FIG. 2, as the transmitter 210 transmits information to the receiver 230 through the main channel after encoding, the transmitter 210 may obtain information by decoding the receiver 230. In this case, the eavesdropper 220 may eavesdrop information transmitted from the transmitter 210 through a wiretap channel, and the eavesdropper 220 may also obtain information through decoding.

Here, secrecy capacity C _S = [C _Bob -C _Eve ] ⁺ . This will be described in more detail below.

3 is a flowchart illustrating a physical layer security method for cooperative multihop routing in an ad-hoc wireless network according to an embodiment.

Referring to FIG. 3, a physical layer security method for cooperative multihop routing in an ad-hoc wireless network according to an embodiment may include transmitting information from a transmitter in an ad-hoc wireless network environment in which an eavesdropper exists. Receiving the transmitted information through at least one or more of the plurality of relays (relay) of the plurality of hops, and transmitting to the receiver 320, and receiving the information via the relay at the receiver (330) It can be made, including.

Herein, receiving and transmitting the information through at least one or more of the plurality of relays of the plurality of hops and transmitting the information to the receiver may select at least one or more relays from each relay cluster of the plurality of hops and transmit the information. Can be.

Hereinafter, a physical layer security method for cooperative multihop routing in an ad-hoc wireless network according to an embodiment will be described as an example.

A physical layer security method for cooperative multihop routing in an ad-hoc wireless network according to an embodiment may be described in detail with reference to FIG. 4. The security system 400 may be described in more detail. In an ad-hoc wireless network according to an embodiment, the physical layer security system 400 for cooperative multihop routing may include a transmitter 410, an intermediate cluster 420, and a receiver 430.

In step 310, the transmitter 410 may transmit information in an ad-hoc wireless network environment where the eavesdropper 440 is present.

In operation 320, the intermediate cluster 420 may receive the transmitted information through at least one or more of the plurality of relays of the plurality of hops, and transmit the received information to the receiver 430.

The intermediate cluster 420 may transfer information by selecting at least one relay from each relay cluster of the plurality of hops. More specifically, the hop-by-hop optimal security relay is selected in each relay cluster based on the instantaneous channel conditions of the receiver 430 and the eavesdropper 440 in each hop to apply a secure routing technique. A message can be sent. Here, the relay is a decode and forward (DF) relay, which decodes and re-encodes the digitally received signal from the preceding node to prevent eavesdropping before retransmitting through a wireless fading channel called the main channel. can do.

The intermediate cluster 420 is based on the instantaneous signal-to-noise ratio (SNR) of the main channel at each hop and the instantaneous signal-to-noise ratio (SNR) of the eavesdropper 440 channel. By subtracting the instantaneous capacity, the secrecy capacity probability can be derived. The intermediate cluster 420 may calculate the cumulative distribution function CDF of the secret signal-to-noise ratio SNR at each hop, and select a relay having the maximum secret signal-to-noise ratio SNR at each hop.

In addition, the intermediate cluster 420 can derive a probability of secrecy outage that is a probability that the instantaneous end-to-end transmission rate drops below a given threshold secrecy rate (Rs) to quantify secrecy performance. .

를 정의하며,

및

로 초기화한 후, 각각의 홉 k = 1, ... , K-2에서 선택된 최대 보안유지 릴레이를 구하고, 홉 K-1에서, 가장 큰

을 경로로 선택하는 대신

로 조인트 릴레이를 선택하며, 최적의 비밀유지 릴레이 {

}를 결정할 수 있다.Moreover, the intermediate cluster 420 may use an algorithm (Table 1) to enforce a secure multihop routing policy. The algorithm sets the number of hops and the number of relay relay relays for each, and the index of the selected relay node on each hop.

Defines the

And

After initializing to, obtain the maximum security relay selected at each hop k = 1, ..., K-2, and at hop K-1,

Instead of choosing

Select joint relay and the best confidentiality relay {

} Can be determined.

In operation 330, the receiver 430 may receive information through a relay. In this case, the receiver 430 may receive a secret message minimized by the eavesdropper 440. By applying the cooperative routing scheme as described above, the maximum diversity effect between each hop can be achieved.

4 is a diagram schematically illustrating a physical layer security system for cooperative multihop routing in an ad-hoc wireless network according to an embodiment.

4 shows a linear network model with K hops and N reliable relays (R1-R) in each cluster, with a transmitter 410 called Alice (A) with a K-1 relay cluster ( Source node), a legitimate receiver 430 called Bob (B), and an eavesdropper 440 called Eve (E). That is, a physical layer security system for cooperative multihop routing in an ad-hoc wireless network according to an embodiment may include a transmitter 410, an intermediate cluster 420, and a receiver 430. Here, the intermediate cluster 420 may be composed of a plurality of relay clusters, and each relay cluster may be composed of a plurality of relays (relay nodes).

Linear network models are commonly used in wireless communications involving sensors and vehicle networks. Each relay cluster may be composed of N DF relay nodes R1 to RN. The transmitter Alice 410 and the receiver Bob 430 have no direct link and can communicate with the help of reliable relays in each cluster. Each intermediate relay may decode and re-encode the digitally received signal at the node immediately preceding it before retransmitting it over a wireless fading channel called the main channel.

Meanwhile, the eavesdropper 440 may attempt to decode the message through the eavesdropping channel for each hop. Assuming that a random codebook is used at each hop to confuse the eavesdropper 440, it can be assumed that the eavesdropper 440 is not capable of joint decoding. This linear network model is equivalent to the presence of eavesdropper 440 in each cluster that does not conspire with each other. At each hop, you can choose the best security relay to deliver confidential messages. Every node can be considered to be equipped with one antenna. It can also be assumed that the distance between each cluster is significantly greater than the distance between relay nodes in any cluster.

As such, the channel gains of the hops may be distributed independently as well as the same distribution. In addition, it may be assumed that the transmitter 410 has overall channel state information (CSI) of the main channel and the eavesdropping channel. This is a widely adopted assumption in the existing literature on communication systems with confidentiality constraints. In this scenario, some relays are fully trusted, while others are commonly seen in heterogeneous networks that are unreliable due to low authentication grants and QoS settings. Although both types of relays actively participate in communication, the transmitter 410 may not prefer an untrusted relay to send a predetermined confidential message to a specific legitimate receiver 430, and an untrusted relay may eavesdrop May be considered a child 440. Thus, the transmitter 410 may have both channel state information (CSI) of a reliable relay (main channel) and an unreliable relay (tapping channel).

로 나타낼 수 있다. 여기서, r1, r2

{1, 2, ..., N}이고 k

{1, 2, ..., K}이다. 첫 번째 홉에는 송신기(410)가 하나만 있고, 이는 k = 1일 때에 r1 = A인 송신기(Alice, 410)이다. 마찬가지로 마지막 홉에서도 수신기(430)는 오직 한 개이며, 이는 k = K일 때에 r2 = B인 수신기(Bob, 430)이다.　반면,

를 홉 k에서 릴레이 r1부터 도청자(Eve, 440)까지의 도청 채널의 채널 계수로 정의할 수 있다. 이 경우에도, 첫 번째 홉에는 송신기(410)가 하나만 있고, 그 결과 k = 1일 때에 r1 = A이다. All channels are considered quasi-static Rayleigh fading. In hop k, the channel coefficients of the main channel from relay r1 to relay r2

It can be represented as. Where r1, r2

{1, 2, ..., N} and k

{1, 2, ..., K}. There is only one transmitter 410 in the first hop, which is the transmitter Alice (410), where r1 = A when k = 1. Similarly, there is only one receiver 430 in the last hop, which is receiver Bob 430 with r2 = B when k = K. On the other hand,

May be defined as the channel coefficient of the eavesdropping channel from the relay r1 to the eavesdropper (Eve, 440) at hop k. Even in this case, there is only one transmitter 410 in the first hop, whereby r1 = A when k = 1.

와

인 부가 백색 가우스 잡음(Additive White Gaussian Noise, AWGN)의 분산을 가진다고 가정하고, 홉 k에서의 메인 링크의 순간 신호대잡음비(Signal to Noise Ratio, SNR)는 다음과 같이 정의할 수 있다.Each node has the same level of transmit power at the receiver

Wow

Assuming that the additive white Gaussian noise (AWGN) has a variance, the signal-to-noise ratio (SNR) of the main link at hop k can be defined as follows.

[Equation 1]

In addition, the instantaneous signal to noise ratio (SNR) of the eavesdropper 440 link can be defined as follows.

[Equation 2]

The instantaneous secrecy capacity achievable at hop k can be expressed as follows.

[Equation 3]

은 다음에 의해 주어진 홉 k에서의 메인 채널의 순간 용량이다.here,

Is the instantaneous capacity of the main channel at hop k given by

[Equation 4]

는 홉 k에서 주어진 도청 채널의 순간 용량이다.And,

Is the instantaneous capacity of the eavesdropping channel given in hop k.

[Equation 5]

Unless specified here, the log can be assumed on the default two scales. To facilitate analysis, the confidentiality signal to noise ratio (SNR) can be defined as:

[Equation 6]

{M, W}을 도입함으로써,

의 확률밀도함수(Probability Density Function, PDF)와 누적분포함수(Cumulative Distribution Function, CDF)를 각각 다음 식과 같이 표현할 수 있다.General Notation Z

By introducing {M, W},

Probability Density Function (PDF) and Cumulative Distribution Function (CDF) can be expressed as follows.

[Equation 7]

[Equation 8]

은 홉 k의 모든 링크에 대한 평균 신호대잡음비(SNR)다. 수학식6 내지 수학식 8로부터, 홉 k에서의 비밀유지 신호대잡음비(SNR)의 누적분포함수(CDF)는 다음과 같이 얻을 수 있다.here,

Is the average signal-to-noise ratio (SNR) for all links of hop k. From Equations 6 to 8, the cumulative distribution function CDF of the confidentiality signal-to-noise ratio SNR at hop k can be obtained as follows.

[Equation 9]

The following describes in more detail secure multi-hop routing.

The routing policy proposed here has an ad-hoc characteristic, and each relay can select a relay having a maximum confidentiality signal to noise ratio (SNR). Intuitively, it can be seen that the opportunity selection at each hop can contribute to the diversity gain of relay N. However, there is one receiver 430 in the last hop K. The same relay selection approach in the last hop does not provide diversity benefits. As such, in order to achieve full diversity in the last hop, joint relay selection based on SNR may be performed in the last two hops.

이며, 여기서

는 홉 k-1에서 선택된 릴레이가 된다. 홉 K-1에서는, 가장 큰

을 경로로 선택하는 대신

로 조인트 선택을 수행할 수 있다.　

이고

인 것은 명백하다.　라우팅 정책은 표 1의 알고리즘 1과 같이 요약될 수 있다. The maximum security relay selected at hop k = 1, ..., K-2

, Where

Becomes the relay selected in hop k-1. In hop K-1, the largest

Instead of choosing

Joint selection can be performed with

ego

It is obvious. The routing policy may be summarized as shown in Algorithm 1 of Table 1.

TABLE 1

Of all possible paths, identifying the path with the least end-to-end outage probability is an optimal policy, but it requires high channel state information (CSI) on all links with co-optimization of all paths. This requires a level of complexity and significant feedback. The ad-hoc nature of the proposed routing policy can significantly reduce feedback and complexity.

The proposed policy requires channel state information (CSI) of N links on each hop, whereas 2N links are needed for joint selection on the last two hops. On the other hand, (N-1) comparisons are needed for the first K-2 hop and (2N-1) comparisons for the last hop. As such, the total number of comparisons required for this policy is K (N -1) +1.

For performance evaluation, distribution of end-to-end confidentiality signal-to-noise ratio (SNR) at the receiver Bob (430) should be obtained. Since assuming a DF relay, the instantaneous end-to-end secrecy rate depends on the minimum secret signal-to-noise ratio (SNR) between K hops that acts as a bottleneck. Therefore, the end-to-end secret signal-to-noise ratio (SNR) of the receiver Bob 430 can be obtained as follows.

[Equation 10]

는 k = 1,...,K-2의 경우

로, k = K-1의 경우

로 표시된다.　또한, 이는 다음과 같이 표현할 수 있다.here,

For k = 1, ..., K-2

For k = K-1

Is displayed. It can also be expressed as follows.

[Equation 11]

[Equation 12]

의 누적분포함수(CDF)을 구할 수 있다.Using ordinal statistics, in Equations 9 and 11,

The cumulative distribution function of (CDF) can be found.

[Equation 13]

홉에 따라서도 달라진다.　따라서,

에 대한 누적분포함수(CDF)는 다음과 같이 계산될 수 있다.For hop K-1, the relay selection is

It depends on the hop. therefore,

The cumulative distribution function (CDF) for can be calculated as

[Equation 14]

이다. 여기에서는 다음과 같이 알고 있다.here,

to be. Here is what we know:

[Equation 15]

Then, the followings can be obtained from equations (8), (12), (14) and (15).

[Equation 16]

의 누적분포함수(CDF)를 얻을 수 있다.After a simple mathematical operation, finally

The cumulative distribution function of (CDF) can be obtained.

[Equation 17]

Using the ordinal statistics, the cumulative distribution function (CDF) of the end-to-end confidentiality signal-to-noise ratio (SNR) in Equation 10 can be obtained as follows.

Equation 18

Since the distribution of the end-to-end confidentiality signal-to-noise ratio (SNR) is different in the first K-2 hops and the last two hops, Equation 18 may be represented as follows.

[Equation 19]

Equations 13 and 17 can be simplified.

Below you can perform a performance assessment.

First, we can determine the probability of non-zero secrecy capacity. The instant end-to-end confidentiality capacity is expressed as follows.

[Equation 20]

Factor 1 / K accounts for the fact that the entire transfer occurs in the K phase. Since the confidentiality capacity exists only when the SNR of the main channel is greater than the SNR of the eavesdropping channel, it is necessary to investigate the possibility of non-zero secrecy capacity. From Equation 20 can be obtained as follows.

[Equation 21]

A closed expression for non-zero secrecy capacity probability may be obtained by replacing x with 1 by combining Equation 13, Equation 17, Equation 19, and Equation 21 as follows.

[Equation 22]

는 다음과 같이 정의될 수 있다.here,

May be defined as follows.

[Equation 23]

You can also check the probability of secrecy outage.

인 경우에만 안전한 전송이 보장된다. 따라서, 비밀유지 아웃티지 확률은 다음과 같이 나타낼 수 있다.By deriving the correct confidentiality outage probabilities from closed expressions, we can quantify the confidentiality performance achieved by the proposed policy. The confidentiality outage probability may be defined as the probability that the instantaneous end-to-end transmission rate falls below a given threshold confidentiality rate (Rs). This way

Only secure transmission is guaranteed. Therefore, the confidentiality outage probability can be expressed as follows.

[Equation 24]

로 대체하여 수학식 3, 수학식 17 및 수학식 19에서 다음과 같이 쉽게 얻을 수 있다. 즉, 비밀유지 아웃티지 확률을 다음과 같이 나타낼 수 있다. As such, the closed expression for the confidentiality probability is x

In Equation 3, Equation 17 and Equation 19 can be easily obtained as follows. That is, the probability of confidentiality outage can be expressed as follows.

[Equation 25]

here,

[Equation 26]

[Equation 27]

이다.ego,

to be.

로 점근적 분석을 연구할 수 있다.Although this closed expression can evaluate the performance of the proposed policy, this complex expression does not provide useful insight into how diversity gains are affected. Thus, a high confidentiality signal-to-noise ratio (SNR) approximation, ie,

Asymptotic analysis can be studied.

일 때 점근적 아웃티지 확률은 다음과 같이 나타낼 수 있다.Theory 1.

The asymptotic outage probability can be expressed as

[Equation 28]

proof. The end-to-end cumulative distribution function (CDF) of the confidentiality signal-to-noise ratio (SNR) can be simplified as follows:

[Equation 29]

의 곱이

에 비해 작다는 사실에서 근사치를 구할 수 있다.　여기에서는

일 때

인 것을 안다. 또한 수학식 13 및 수학식 17의 익스퍼넨셜 텀을 확장하고 상위 차수 항을 무시하면 누적분포함수(CDF)를 다음과 같이 다시 나타낼 수 있다.

Multiply by

We can approximate the fact that it is small compared to. Here

when

I know it is. In addition, by expanding the expression terms of Equations 13 and 17 and ignoring higher order terms, the cumulative distribution function (CDF) may be represented as follows.

Equation 30

Equation 31

In Equations 29 to 31, the following can be obtained.

Equation 32

로 대체하면, 수학식 28을 얻을 수 있다.Where x

Substituting the equation into Eq. (28) can be obtained.

), 점근적 아웃티지 표현이 다음과 같이 감소할 수 있다.A special case of a balanced link with the same average signal-to-noise ratio (SNR) on all links of the main channel (eg

Asymptotic outage expression can be reduced to

[Equation 33]

=N 이고, 동등 비밀유지 아웃티지 신호대잡음비(SNR) 이득은

=

이다.　비밀유지 다양성 차수

는 점근적 비밀유지 아웃티지 확률 곡선의 기울기를 구하기 쉽게 한다.　비슷하게, 비밀유지 아웃티지 신호대잡음비(SNR) 이득은 기준 곡선

에 관련된 점근적 비밀유지 아웃티지 확률의 신호대잡음비(SNR) 장점을 결정할 수 있다.Where the degree of confidentiality diversity

= N and the equivalent confidentiality outage signal to noise ratio (SNR) gain is

=

to be. Confidentiality Diversity Order

Makes it easy to find the slope of the asymptotic confidentiality probability curve. Similarly, the confidentiality outage signal-to-noise ratio (SNR) gain is a reference curve.

The signal-to-noise ratio (SNR) advantage of the asymptotic confidentiality probability associated with can be determined.

및 N이 커지고 K가 작아질수록 non-zero 비밀유지 용량 확률이 커지는 것을 확인할 수 있다.5A illustrates a result of comparing a non-zero secrecy capacity probability and an average main channel signal to noise ratio (SNR) according to an embodiment. As shown in FIG. 5A,

And as N increases and K decreases, the probability of non-zero secrecy capacity increases.

가 커질수록 비밀유지 아웃티지 확률이 커지는 것을 확인할 수 있다. 5B illustrates a result of comparing the confidentiality probability and the average main channel signal to noise ratio (SNR) according to an embodiment. As shown in FIG. 5B, K and

As the value increases, the probability of confidentiality outage increases.

6A illustrates a result of comparing the confidentiality outage probability and the average main channel signal to noise ratio (SNR) according to an embodiment. As shown in FIG. 6A, as N increases, the probability of confidentiality outage decreases.

6B also illustrates a confidentiality outage probability according to the threshold secrecy rate Rs according to an embodiment. As shown in FIG. 6B, it can be seen that as the Rs increases, the confidentiality probability increases.

As such, the asymptotic curve is merged with the correct curve at high signal-to-noise ratio (SNR), and the diversity gain is influenced by N, as can be seen by changing the slope. Multihops are also superior as the Rs are smaller, and each hop can take advantage of the spatial diversity provided by several reliable relays.

The apparatus described above may be implemented as a hardware component, a software component, and / or a combination of hardware components and software components. For example, the devices and components described in the embodiments include, for example, processors, controllers, arithmetic logic units (ALUs), digital signal processors, microcomputers, field programmable arrays (FPAs), It may be implemented using one or more general purpose or special purpose computers, such as a programmable logic unit (PLU), microprocessor, or any other device capable of executing and responding to instructions. The processing device may execute an operating system (OS) and one or more software applications running on the operating system. The processing device may also access, store, manipulate, process, and generate data in response to the execution of the software. For convenience of explanation, one processing device may be described as being used, but one of ordinary skill in the art will appreciate that the processing device includes a plurality of processing elements and / or a plurality of types of processing elements. It can be seen that it may include. For example, the processing device may include a plurality of processors or one processor and one controller. In addition, other processing configurations are possible, such as parallel processors.

The software may include a computer program, code, instructions, or a combination of one or more of the above, and configure the processing device to operate as desired, or process it independently or collectively. You can command the device. Software and / or data may be any type of machine, component, physical device, virtual equipment, computer storage medium or device in order to be interpreted by or to provide instructions or data to the processing device. It can be embodied in. The software may be distributed over networked computer systems so that they may be stored or executed in a distributed manner. Software and data may be stored on one or more computer readable recording media.

The method according to the embodiment may be embodied in the form of program instructions that can be executed by various computer means and recorded in a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the media may be those specially designed and constructed for the purposes of the embodiments, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tape, optical media such as CD-ROMs, DVDs, and magnetic disks, such as floppy disks. Magneto-optical media, and hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like.

Although the embodiments have been described by the limited embodiments and the drawings as described above, various modifications and variations are possible to those skilled in the art from the above description. For example, the described techniques may be performed in a different order than the described method, and / or components of the described systems, structures, devices, circuits, etc. may be combined or combined in a different manner than the described method, or other components. Or even if replaced or replaced by equivalents, an appropriate result can be achieved.

Therefore, other implementations, other embodiments, and equivalents to the claims are within the scope of the claims that follow.

Claims (8)

A physical layer security method for cooperative multihop routing in an ad-hoc wireless network,
Transmitting information at the transmitter in an ad-hoc wireless network environment where the eavesdropper is present;
Receiving the transmitted information through at least one or more of a plurality of relays of a plurality of hops, and transmitting the received information to a receiver; And
Receiving information through the relay from the receiver
Including,
Receiving the information through at least one or more of the plurality of relays of the plurality of hops, and transmitting to the receiver,
At least one relay is selected from each relay cluster of a plurality of hops to transmit the information, and each hop is hop-by-hop in each relay cluster based on instantaneous channel conditions of the receiver and the eavesdropper. The selection of the best security relay and the application of secure routing techniques to send confidential messages.
A physical layer security method for cooperative multihop routing in an ad-hoc wireless network, characterized in that the. delete A physical layer security method for cooperative multihop routing in an ad-hoc wireless network,
Transmitting information at a transmitter in an ad-hoc wireless network environment where the eavesdropper is present;
Receiving the transmitted information through at least one or more of a plurality of relays of a plurality of hops, and transmitting the received information to a receiver; And
Receiving information through the relay from the receiver
Including,
Receiving the information through at least one or more of the plurality of relays of the plurality of hops, and transmitting to the receiver,
Selecting at least one relay from each relay cluster of a plurality of hops to transmit the information,
The relay,
Decode and Forward (DF) relay, which decodes and re-encodes a digitally received signal from a preceding node prior to retransmission through a wireless fading channel called the main channel to prevent eavesdropping
A physical layer security method for cooperative multihop routing in an ad-hoc wireless network, characterized in that the. A physical layer security method for cooperative multihop routing in an ad-hoc wireless network,
Transmitting information at the transmitter in an ad-hoc wireless network environment where the eavesdropper is present;
Receiving the transmitted information through at least one or more of a plurality of relays of a plurality of hops, and transmitting the received information to a receiver; And
Receiving information through the relay from the receiver
Including,
Receiving the information through at least one or more of the plurality of relays of the plurality of hops, and transmitting to the receiver,
Select at least one relay from each relay cluster of a plurality of hops to transmit the information,
Receiving the information through at least one or more of the plurality of relays of the plurality of hops, and transmitting to the receiver,
Probability of confidentiality by subtracting the instantaneous capacity of the eavesdropping channel from the instantaneous capacity of the main channel based on the instantaneous signal-to-noise ratio (SNR) of the main channel at each hop and the eavesdropper channel's instantaneous signal-to-noise ratio (SNR) deriving secrecy capacity probability
A physical layer security method for cooperative multihop routing in an ad-hoc wireless network, comprising: a. The method of claim 4, wherein
Receiving the information through at least one or more of the plurality of relays of the plurality of hops, and transmitting to the receiver,
Calculating a cumulative distribution function (CDF) of the secret signal-to-noise ratio (SNR) at each hop; And
Selecting a relay with the maximum confidentiality signal to noise ratio (SNR) on each hop;
The physical layer security method for cooperative multi-hop routing in the ad-hoc wireless network further comprising. A physical layer security method for cooperative multihop routing in an ad-hoc wireless network,
Transmitting information at the transmitter in an ad-hoc wireless network environment where the eavesdropper is present;
Receiving the transmitted information through at least one or more of a plurality of relays of a plurality of hops, and transmitting the received information to a receiver; And
Receiving information through the relay from the receiver
Including,
Receiving the information through at least one or more of the plurality of relays of the plurality of hops, and transmitting to the receiver,
Select at least one relay from each relay cluster of a plurality of hops to transmit the information,
Receiving the information through at least one or more of the plurality of relays of the plurality of hops, and transmitting to the receiver,
Deriving a probability of secrecy outage, where the instantaneous end-to-end transmission rate falls below a given threshold secrecy rate (Rs) to quantify secrecy performance.
A physical layer security method for cooperative multihop routing in an ad-hoc wireless network, comprising: a. A physical layer security method for cooperative multihop routing in an ad-hoc wireless network,
Transmitting information at the transmitter in an ad-hoc wireless network environment where the eavesdropper is present;
Receiving the transmitted information through at least one or more of a plurality of relays of a plurality of hops, and transmitting the received information to a receiver; And
Receiving information through the relay from the receiver
Including,
Receiving the information through at least one or more of the plurality of relays of the plurality of hops, and transmitting to the receiver,
Select at least one relay from each relay cluster of a plurality of hops to transmit the information,
Receiving the information through at least one or more of the plurality of relays of the plurality of hops, and transmitting to the receiver,
Performing a Secure Multihop Routing Policy Using an Algorithm
Including,
Performing a secure multi-hop routing policy using the algorithm,
Setting the number of hops and each relay cluster relay number;
Index of the selected relay node on each hop

Defining;

And

Initializing to;
Obtaining a maximum security relay selected at each hop k = 1, ..., K-2;
In hop K-1, the largest

Instead of choosing

Selecting a furnace joint relay; And
Optimal confidentiality relay {

} Steps to Determine
A physical layer security method for cooperative multihop routing in an ad-hoc wireless network, comprising: a. A physical layer security system for cooperative multihop routing in an ad-hoc wireless network,
A transmitter for transmitting information in an ad-hoc wireless network environment where the eavesdropper is present;
An intermediate cluster that receives the transmitted information through at least one or more of a plurality of relays of a plurality of hops and delivers the information to a receiver; And
Receiver to receive information through the relay
Including,
The intermediate cluster,
At least one relay is selected from each relay cluster of a plurality of hops to transmit the information, and each hop is hop-by-hop in each relay cluster based on instantaneous channel conditions of the receiver and the eavesdropper. The selection of the best security relay and the application of secure routing techniques to send confidential messages.
A physical layer security system for cooperative multihop routing in an ad-hoc wireless network, characterized in that.

Images