Method for detecting gray hole node in wireless mesh network

Abstract

The invention discloses a method for detecting a gray hole node in a wireless mesh network. The method is characterized in that after forwarding a data packet, an MR (mesh route) node or an MC (mesh client) of the wireless mesh network records retransmission frequency of the forwarded data packet, continues to monitor conditions of a data packet forwarded by a downstream node, adds monitoring information into the data packet and sends the data packet to a gateway node incidentally; after receiving the data packet with the monitoring information, the gateway node stores forwarding success rate information and retransmission frequency rate information of the data packet into a matrix, and periodically judges the gray hole node according to matrix information; if the gray hole node is judged out by the gateway node, gray hole node information is added into an announcement, broadcasting to the whole network to be the gateway node, of the gateway node; after other nodes in the network receives the announcement, the gray hole node is excluded from the network if the gray hole node information added in the announcement is found.

Description

technical field [0001] The invention relates to the fields of wireless network and security, in particular to a gray hole node detection method in a wireless mesh network. Background technique [0002] A typical wireless mesh network (WMN, Wireless Mesh Network) architecture consists of an access layer, a Mesh routing layer, and a Mesh terminal layer, and belongs to a hierarchical network structure that mixes centralized control and distributed control. The access layer consists of Mesh Gateway (MG) nodes, connected to the wired network through wired links. The mesh routing layer usually consists of fixed mesh routing (MR) nodes, providing multi-hop wireless backhaul between the access layer and the mesh terminal layer. The Mesh terminal layer is composed of Mesh client (MC) nodes with mobility, which can directly access the network through MR nodes or other MC nodes. That is to say, MC nodes can also form a multi-hop network. The characteristics of WMN such as dynamic sel...

AI Technical Summary

Problems solved by technology

The problem with this method is: (1). An MR node judges whether its downstream node is a suspected gray hole node, and then judges that V is a gray hole node based on whether two different MR nodes claim that node V is a suspected gray hole node Node, lack of comprehensive judgment; if node V is a normal node, but some two MR nodes collude to claim that node V is a suspicious gray hole node, then V will be judged as a gray hole node, which will cause misjudgment

(2). Each MR node judges whether the downstream node is a suspicious gray hole node, and broadcasts in the whole network; this means that if node V is a gray hole node, its neighbors will broadcast to the whole network, which will cause broadcast storm problem

(3). This method does not consider the packet loss caused by the link quality problem, so it is not practical when detecting gray hole nodes in the actual environment

The problem of the CAD method is: (1). The CAD method requires the MR node to be stationary, and based on this precondition, the corresponding normal packet loss rate is proposed, but in the WMN, the MC can be stationary or mobile, so the CAD method It cannot be applied to the detection of whether the MC node is a gray hole node; (2). The source node needs to send additional probe packets and challenge packets, and generate corresponding probe feedback packets and link quality evidence packets, which will generate a large route (3). When the destination node or gateway node receives the detection packet to judge the suspicious gray hole node, it only judges whether the MR node is Suspicious gray hole nodes, which lack comprehensive judgment, will cause local effect problems that are judged only within the scope of the communication path between a pair of source nodes and destination nodes; (4). In terms of the process of excluding gray hole nodes, CAD The method is that the destination node or the gateway node sends the list of suspicious nodes to the source node, and the source node inquires the suspicious node; if the suspicious node is determined to be a gray hole node, the source node will notify the whole network, which means that if a certain A node is a gray hole node, and this gray hole node is located on multiple paths, the source nodes of these paths will notify the entire network of this gray hole node

[0006] There are four problems in the existing gray hole node detection method in the wireless mesh network: (1). In the aforementioned prior art, it is detected whether the MR node in the WMN is a gray hole node, and based on the assumption that the MR node is a static node Carry out corresponding model design and algorithm analysis; however, for WMN, MC nodes are more vulnerable to attack and become gray hole nodes

But MC nodes can be mobile, therefore, the gray hole attack detection method in the aforementioned technology is not suitable for mobile MC node scenarios

(2). In WMN, due to the unstable link quality, when data packet loss occurs, it is difficult to distinguish whether it is caused by poor link quality or malicious packet loss by gray hole nodes

Although the aforementioned prior art, such as the CAD method, also proposes the judgment of gray hole attacks combined with link quality, its assumption of node quiescence makes the algorithm not universal

(3). The aforementioned existing technologies, such as the CAD method, not only require the source node to send additional probe packets to initiate the collection process of monitoring information, but also require the source node to send additional query packets to obtain the link quality of suspicious gray hole nodes Evidence, this will bring a large routing overhead

(4). None of the above-mentioned prior art utilizes the structural characteristics of WMN centralized control and distributed control, or it is judged by the destination node or the gateway node, and the judgment result of the suspicious gray hole node is sent to the source node, and then the The source node makes the final decision, which will produce the local effect problem and broadcast storm problem that are only judged within the scope of the communication path between a pair of source nodes and destination nodes; Hole nodes, and each node independently broadcasts the judgment result of the gray hole node, which will cause the problem of broadcast storm