KR100640003B1 - How to set keys on wireless sensor network - Google Patents

Abstract

The present invention relates to a key setting method in a wireless sensor network, comprising the steps of: (a) assigning each sensor node pairwise keys for all sensor nodes linked to and associated with it; (b) determining whether there is a common pairwise key among pairwise keys stored in each of the source node and the destination node to which communication is to be performed; And (c) if it is determined that there is no common pairwise key, transmitting a random key generated at the source node to a destination node using a path of other sensor nodes having a common pairwise key. There is no communication and computational overhead for keying, and it can support a large number of sensor networks, effectively keying in resource-constrained wireless sensor networks.

Description

Key setting method in wireless sensor network {Method for key-distribution in wireless sensor network}

1 is a flowchart illustrating a key setting method in a wireless sensor network according to an embodiment of the present invention.

2 is a flowchart illustrating step S130 of FIG. 1 in more detail.

3 is a flowchart illustrating step S220 of FIG. 2 in more detail.

FIG. 4 is a diagram illustrating information about a sensor node and a pairwise key assigned to each sensor node when m = 4 in FIG. 1.

The present invention relates to a key setting method in a wireless sensor network, and more particularly, to a key setting method among sensor nodes which are essential elements for providing a security service such as authentication and encryption in a wireless sensor network. .

A wireless sensor network consists of a large number of sensor nodes with limited energy, storage space, computational and communication capabilities. Unlike a typical network, sensor nodes in a wireless sensor network can often be deployed in environments that are vulnerable to physical attacks. As such, sensor nodes have limited energy, storage space, communication, and computation capabilities, making it difficult to apply a general key setting method using public key cryptography. In this environment, an attacker can capture nodes and eavesdrop or change data or control information between two sensor nodes. Such attacks can pose a serious threat to the entire wireless sensor network.

Accordingly, security services that provide confidentiality and authentication for the construction of a secure wireless sensor network are an important factor, and there are many key pre-distribution methods for distributing key related information to all sensor nodes before the sensor node is placed in the wireless sensor network. I'm getting attention.

Sensor nodes can often be placed in physically insecure environments. In such an environment, an attacker can acquire a sensor node, which can extract sensitive information, including keys within the sensor node. For this reason, one of the most important purposes of the key pre-distribution method for applying to a wireless sensor network is to provide a method having perfect resilience against a sensor node capture attack. Full fault tolerance means that the captured sensor node does not reveal any information about the link that it does not contain.

The key pre-distribution method with full fault tolerance is representatively two methods as follows.

The first method is the "random pairwise keys scheme" proposed by H. Chan et al. In IEEE Symposium on SP 2003. This method has the advantage that there is no communication and computation overhead when setting up a direct pairwise key. The problem is that it is strictly limited.

The second method is the "grid based key pre-distribution scheme" proposed by D. Liu and P. Ning in ACM CCS 2003. This method can be transformed into a key pre-distribution method with full modifications with a few modifications. have. The second method has the advantage of being able to support a much larger network than the first method, but requires a large number of modular multiplications for direct pairwise keying. This calculation has a problem that it is a burden on the resource-constrained sensor nodes.

The present invention to solve the above problems, there is no communication and computational overhead for direct pairwise key setting between the sensor nodes, a complete failure that can support a much larger sensor network compared to the conventional random pairwise scheme Provided are a key setting method in a wireless sensor network having tolerance.

According to an aspect of the present invention, there is provided a key setting method in a wireless sensor network, the method comprising: (a) assigning pairwise keys for all sensor nodes linked to and associated with each sensor node; (b) determining whether there is a common pairwise key among pairwise keys stored in each of the source node and the destination node to which communication is to be performed; And (c) if it is determined that there is no common pairwise key, transmitting a random key generated at the source node to a destination node using a path of other sensor nodes having a common pairwise key. Have

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

1 is a flowchart illustrating a key setting method in a wireless sensor network according to an embodiment of the present invention. Referring to FIG. 1, first, before a sensor node is placed in a sensor network, the setup server allocates pairwise keys for all sensor nodes located in association with each sensor node itself (S100).

Next, two sensor nodes to perform communication determine whether there is a common pairwise key among the stored pairwise keys (S110). If it is determined in step S110 that there is a common pairwise key, the flow proceeds to step S120 to set pairwise keys common to each other as a common key. On the other hand, if it is determined in step S110 that there is no common pairwise key, the flow proceeds to step S130.

In step S130, the random key generated from the source node of the two sensor nodes is transmitted to the destination node using the paths of other sensor nodes having a common pairwise key.

Hereinafter, a more detailed operation of the present invention will be described.

First, step S100 of allocating pairwise keys for all sensor nodes located in association with each sensor node itself before the sensor node is placed in the wireless sensor network will be described in more detail.

이라고 한다. 여기에서 각각의 센서 노드에 대한 식별자(ID)를

,

이라고 한다. 예를 들어, 무선 센서 네트워크가 16개의 센서 노드를 가진다고 하는 경우 m은 4가 된다.Let's say the whole sensor network has n sensor nodes, and m

It is called. Here you can find the identifier (ID) for each sensor node

,

It is called. For example, if a wireless sensor network has 16 sensor nodes, then m is 4.

Step S100 is performed before the sensor node is placed in the wireless sensor network, and the process is as follows.

에 대해 다음과 같은 센서 노드들과의 2(m-1)개의 유일한 pairwise 키를 랜덤하게 선택한다.The setup server of the wireless sensor network has its own sensor node.

We randomly select 2 (m-1) unique pairwise keys with the following sensor nodes.

,

,

에게 이러한 2(m-1)개의 pairwise 키와 상기 pairwise 키에 해당하는 센서 노드들에 대한 식별자(ID)를 할당한다.The setup server has its own sensor node

Identifies two (m-1) pairwise keys and identifiers (IDs) for sensor nodes corresponding to the pairwise keys.

More specifically, the case where the wireless sensor network consists of 16 sensor nodes, that is, m = 4 is as follows.

The setup server assigns the sensor nodes (0,0) with the following six pairwise keys and identifiers for the sensor nodes corresponding to each key. Here, six pairwise keys are assigned to sensor nodes (0,0) and six sensor nodes (0,1), (0,2), (0,3), (1,0), (2,0), With the pairwise key between (3,0), the six sensor nodes selected are the sensor nodes located in the same row and column as the sensor node (0,0).

,

,

,

,

,

,

,

,

,

,

은 센서 노드(i,j)와 노드(k,l) 사이에 공유된 유일한 pairwise 키를 의미한다. 또한,

를 만족한다.From here,

Denotes a unique pairwise key shared between sensor node (i, j) and node (k, l). Also,

Satisfies.

The setup server also assigns the sensor nodes (1,0) with the following six pairwise keys and identifiers for the sensor nodes corresponding to each key: Here, six pairwise keys are assigned to sensor node (1,0) and six sensor nodes (0,0), (2,0), (3,0), (1,1), (1,2), With the pairwise key between (1, 3), the six sensor nodes selected are the sensor nodes located in the same row and column as the sensor node (1, 0).

,

,

,

,

,

,

,

,

,

,

Through the above method, the setup server is connected to the sensor nodes (2,0), (3,0), (0,1), (1,1), (2,1), (3,1), (0, 2), (1,2), (2,2), (2,3), (0,3), (1,3), (2,3), and (3,3), each with its own row It assigns six pairwise keys with the sensor nodes located in the column and identifiers for the sensor nodes corresponding to each key.

The order of arrangement of sensor nodes in a wireless sensor network is as follows.

(0,0), (0,1), ..., (0, m-1), (1,0), (1,1), ... (1, m-1), ... (m-1,0), ... (m-1, m-1)

Of course, with respect to the arrangement order for such sensor nodes can be deployed in a number of different ways.

Next, step S110 of determining whether there is a common pairwise key among the stored pairwise keys by each of the two sensor nodes to perform communication will be described in more detail. Here, the starting node is called the source node and the arriving node is called the destination node for the two sensor nodes to communicate with.

또는

를 만족하는지 여부를 판단하는 것이다. 구체적으로 예를 들어, 센서 노드 (2,1) 과 (3,1)은 공통된 pairwise 키로

을 공유함을 볼 수 있다.Whether or not there is a common pairwise key in step S110 is determined by the source node (i, j) and the destination node (k, l).

or

It is to determine whether or not to satisfy. Specifically, for example, sensor nodes (2,1) and (3,1) have a common pairwise key.

You can see it shared.

As described above, when it is determined in step S110 that there is a common pairwise key, the process proceeds to step S120 to set pairwise keys common to each other as common keys. On the other hand, if it is determined in step S110 that there is no common pairwise key, the flow proceeds to step S130.

,

을 만족하는 경우이다. 이러한 경우에 소스 노드(i,j)와 목적지 노드(k,l)는 공통된 pairwise 키를 가지지 않게 된다.If it is determined in step S110 that there is no common pairwise key, the source node (i, j) and the destination node (k, l) are determined.

,

If is satisfied. In this case, the source node (i, j) and the destination node (k, l) do not have a common pairwise key.

Next, step S130 of transmitting the random key generated from the source node among the two sensor nodes to the destination node using the paths of the other sensor nodes having the common pairwise key will be described in more detail with reference to FIG. 2.

2 is a flowchart illustrating step S130 of FIG. 1 in more detail.

Referring to FIG. 2, first, an intermediate sensor node having a pairwise key common to each of a source node and a destination node is searched for (S200).

For example, if there is a source node (i, j) and a destination node (k, l) in step S100, they have a common pairwise key for each of the source node (i, j) and the destination node (k, l). There is an intermediate sensor node. Where the intermediate sensor nodes are (j, l) and (k, j).

을 가지고, 목적지 노드(2,3)과 공통된 pairwise 키

을 가지게 된다. 또한, 다른 하나의 중간 센서 노드(2,1)은 소스 노드(1,1)과 공통된 pairwise 키

을 가지고, 목적지 노드(2,3)과 공통된 pairwise 키

을 가지게 된다.FIG. 4 is a diagram illustrating information about a sensor node and a pairwise key assigned to each sensor node when m = 4 in FIG. 1. Hereinafter, a case in which source nodes 1 and 1 and destination nodes 2 and 3 are set in FIG. 4 will be described. The intermediate sensor node becomes (1,3), (2,1) with a common pairwise key for each of the source node (1,1) and the destination node (2,3). That is, the intermediate sensor node 1,3 has a pairwise key in common with the source node 1,1.

Pairwise keys common to the destination nodes (2, 3)

Will have In addition, the other intermediate sensor node 2,1 has a pairwise key common to the source node 1,1.

Pairwise keys common to the destination nodes (2, 3)

Will have

를 생성한다(S210).Next, the source node (1, 1) is a random key

To generate (S210).

를 상기 중간 센서 노드를 거쳐 상기 목적지 노드(2,3)으로 전송한다(S220).Next, a common pairwise key between the source node (1,1) and the intermediate sensor node (1,3) or (2,1) and the intermediate sensor node (1,3) or (2,1) and the destination node. Using a pairwise key in common with (2,3), the source node (1,1) is the random key.

Is transmitted to the destination nodes (2, 3) via the intermediate sensor node (S220).

3 is a flowchart illustrating step S220 of FIG. 2 in more detail. In FIG. 3, the case where the intermediate sensor nodes 1 and 3 are used among the intermediate sensor nodes 1 and 3 and the intermediate sensor nodes 2 and 1 will be described.

로 암호화하고 인증된 메시지 내에 포 함된 소스 노드(1,1)과 목적지 노드(2,3)에 대한 식별자(ID)와 랜덤키

를 중간 센서 노드(1,3)에게 전송한다(S300).Referring to FIG. 3, first, the source node 1, 1 has a common pairwise key with the intermediate sensor node 1, 3.

ID and random key for source node (1,1) and destination node (2,3) encrypted and authenticated in the authenticated message

Is transmitted to the intermediate sensor nodes (1, 3) (S300).

로 인증 및 복호화를 수행한다(S310).Next, the intermediate sensor nodes (1, 3) receiving the message in step S300 is a common pairwise key

Authentication and decryption are performed (S310).

으로 암호화하고 인증된 메시지 내에 포함된 소스 노드(1,1)과 목적지 노드(2,3)에 대한 식별자(ID)와 랜덤키

를 목적지 노드(2,3)에게 전송한다(S320).Next, intermediate sensor nodes (1, 3) have a common pairwise key

Identifier (ID) and random key for source node (1,1) and destination node (2,3) contained in encrypted and authenticated message

Is transmitted to the destination nodes 2 and 3 (S320).

로 인증 및 복호화를 수행한다(S330).Next, the destination node (2,3) receiving the message in step S320 is a common pairwise key with the intermediate sensor node (1,3)

Authentication and decryption are performed (S330).

를 공통키로 설정한다.Next, the source node (1,1) and the destination node (2,3) are random keys

Set to common key.

In the above case, the intermediate sensor nodes 1 and 3 deliver messages to the destination nodes 2 and 3. However, intermediate sensor nodes 1, 3 may be compromised or out of communication range.

In this case, the source nodes 1 and 1 search for other intermediate sensor nodes 2 and 1 without proceeding to step S310.

를 생성한다. 또한, 소스 노드(1,1)은 다른 중간 센서 노드(2,1)와의 공통된 pairwise 키

로 암호화하고 인증된 메시지 내에 포함된 소스 노드(1,1)과 목적지 노드(2,3)에 대한 식별자(ID)와 랜덤키

를 다른 중간 센서 노드(2,1)에게 전송한다. 메시지를 받은 다른 중간 센서 노드(2,1)은 공통된 pairwise 키

로 인증 및 복호화를 수행한다.The source nodes 1 and 1 are random keys

Create In addition, the source node 1,1 has a common pairwise key with other intermediate sensor nodes 2,1.

ID and random key for source node (1,1) and destination node (2,3) encrypted and authenticated in the authenticated message

Is transmitted to another intermediate sensor node (2, 1). The other intermediate sensor node (2,1) receiving the message has a common pairwise key

Authentication and decryption are performed.

으로 암호화하고 인증된 메시지 내에 포함된 소스 노드(1,1)과 목적지 노드(2,3)에 대한 식별자(ID)와 랜덤키

를 목적지 노드(2,3)에게 전송한다. Next, the other intermediate sensor nodes 2,1 have a common pairwise key.

Identifier (ID) and random key for source node (1,1) and destination node (2,3) contained in encrypted and authenticated message

Is transmitted to the destination nodes (2, 3).

를 공통키로 설정한다.Next, the source node (1,1) and the destination node (2,3) are random keys

Set to common key.

In the above, at least one of the intermediate sensor nodes 1 and 3 and the intermediate sensor nodes 2 and 1 operates will be described.

If the intermediate sensor node (1,3) and the intermediate sensor node (2,1) are out of mode or out of communication range, the source node (1,1) has two different sensor nodes (1,2), ( 2,2) or two different sensor nodes (3,1), (3,3), etc., can be used to establish a common key with the destination nodes (2,3). There are 2 (m-2) cases where two different sensor nodes can be used. Even if a conventional path cannot be used due to sensor node damage, a sufficient number of paths can be found. .

In addition, the source nodes 1 and 1 may set a common key with the destination nodes 2 and 3 through not only two but also a plurality of different sensor nodes.

이다.The compromised sensor node does not reveal any information about links that it does not include directly. Thus, the present invention is a method with complete fault tolerance. In addition, the present invention has no communication and computational overhead for direct pairwise key establishment between sensor nodes, and when each sensor node stores 2 (m-1) pairwise keys, the number of networks that can be supported is

to be.

이다. 이를 통하여 많은 수의 센서 노드를 가지는 센서 네트워크를 지원할 수 있게 된다.In the above, an embodiment of the present invention has been described mainly for the method on the two-dimensional, but the present invention is not limited to this and can be easily extended to the t-dimensional technique. In this case, if the sensor node can store t (m-1) keys, then the number of sensor networks that can be supported is

to be. Through this, it is possible to support a sensor network having a large number of sensor nodes.

The invention can also be embodied as computer readable code on a computer readable recording medium. Computer-readable recording media include all types of recording devices that store data that can be read by a computer system. Examples of computer-readable recording media include ROM, RAM, CD_ROM, magnetic tape, floppy disks, and optical data storage, and may also include those implemented in the form of carrier waves (eg, transmission over the Internet). . The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

As described above, optimal embodiments have been disclosed in the drawings and the specification. Although specific terms have been used herein, they are used only for the purpose of describing the present invention and are not intended to limit the scope of the invention as defined in the claims or the claims. Therefore, those skilled in the art will understand that various modifications and equivalent other embodiments are possible from this. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

The key setting method in the wireless sensor network according to the present invention provides a method having complete fault tolerance against a node acquisition attack which is the most threat for the construction of a secure wireless sensor network, thereby providing security services in a wireless sensor network environment. Keying can be set up appropriately among the sensor nodes, which is an essential element. Thus, the compromised sensor node does not reveal any information about the link that it does not contain.

And, the key setting method in the wireless sensor network according to the present invention has no communication and calculation overhead for direct pairwise key setting. Through this, it is possible to provide a key setting method that meets the characteristics of the sensor node, which has limited energy, storage space, communication, and computation capabilities.

In addition, compared to the conventional random pairwise scheme, there is an effect that can be supported for a much larger network.

Claims (13)

(a) assigning each sensor node a pairwise key for all sensor nodes linked in association with it; (b) determining whether there is a common pairwise key among pairwise keys stored in each of the source node and the destination node to which communication is to be performed; And (c) if it is determined that there is no common pairwise key, transmitting a random key generated at the source node to a destination node using a path of other sensor nodes having a common pairwise key; How to set up keys in a wireless sensor network. The method of claim 1, (c ') if it is determined that the common pairwise key is present, the source node and the destination node set the common pairwise key as a common key to perform communication; in the wireless sensor network further comprising: How to set key. The method of claim 1, wherein step (c) (c1) searching for an intermediate sensor node having a common pairwise key for each of the source node and the destination node; (c2) generating a random key at the source node; And (c3) using the common pairwise key between the source node and the intermediate sensor node and the common pairwise key between the intermediate sensor node and the destination node, the source node passes the random key through the intermediate sensor node to the destination. Transmitting to a node; key setting method in a wireless sensor network comprising a. The method of claim 3, wherein In step (a), not only pairwise keys for all sensor nodes linked to and associated with each sensor node but also identifier (ID) information for sensor nodes matching each pairwise key are assigned together. , In step (c3), the intermediate sensor node transmits the identifier information of the destination node together with the random key so that the intermediate sensor node can know the destination node to which the random key is to be transmitted. How to set key. The method of claim 3, wherein step (c3) (c31) the source node encrypting the random key with a pairwise key common to the found intermediate sensor node and transmitting the encrypted random key to the intermediate sensor node; (c32) the intermediate sensor node decrypts the pairwise key in common with the source node, encrypts the decrypted random key with the pairwise key in common with the destination node, and transmits the decrypted random key to the destination node; And (c33) the destination node deciphering with a pairwise key common to the intermediate sensor node to obtain the random key. The method of claim 5, If the source node cannot transmit a random key through the intermediate sensor node between the steps (c31) and (c32), The source node searching for another intermediate sensor node having a path common to each of the source node and the destination node; Encrypting, by the source node, the random key with a pairwise key common to other intermediate sensor nodes retrieved, and transmitting the encrypted random key to the other intermediate sensor node; The other intermediate sensor node decrypts the pairwise key in common with the source node, encrypts the decrypted random key with the pairwise key in common with the destination node, and transmits the decrypted random key to the destination node; And And decrypting, by the destination node, a pairwise key in common with the other intermediate sensor node, to obtain the random key. The method of claim 6, If the source node is unable to transmit the random key through the other intermediate sensor node, The source node searching for a plurality of sensor nodes that can be connected with a destination node through a plurality of paths; And And transmitting, by the source node, the random key to the destination node via a path of the plurality of sensor nodes. The method of claim 5, wherein step (c3) In step (c31), the source node encrypts the random key with a pairwise key common to the found intermediate sensor node, performs authentication, and transmits the random key to the intermediate sensor node. And in step (c32), the intermediate sensor node encrypts the decrypted random key with a common pairwise key with the destination node, performs authentication, and transmits the decrypted random key to the destination node. The method according to claim 1 or 3, and (d) setting the random key as a common key in order for the source node and the destination node to communicate with each other. The method according to claim 1 or 3, In step (a), together with the pairwise keys for all the sensor nodes linked to and linked to each sensor node, the identifier (ID) information for the sensor nodes matching each pairwise key is assigned together. Key setting method in a wireless sensor network, characterized in that. The method according to claim 1 or 3, And the sensor nodes are sensor nodes in an ad hoc environment. The method according to claim 1 or 3, And all sensor nodes located in association with each sensor node in question are all sensor nodes located in their respective rows and columns in the respective sensor node. The method according to claim 1 or 3, The step (a) is a key setting method in the wireless sensor network, characterized in that before each sensor node is placed in the wireless sensor network.

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