A method and system for byzantine fault tolerance broadcast in a wireless network

Abstract

The application discloses a Byzantine fault-tolerant broadcast method and system in a wireless network, comprising the following steps: a source node broadcasts a message in the wireless network; a neighbor node of the source node receives the first broadcast message of the source node in the current round, performs signature authentication on the received first broadcast message, and then broadcasts the message; the neighbor node of the source node collects the first broadcast message of the source node and all neighbor nodes in the current round, generates a credential message from the collected first round broadcast message, and broadcasts the credential message; and any node receives the credential message, verifies the credential message, and then retransmits the credential message after message confirmation. In this way, the communication quality can be ensured, and the communication complexity can be effectively reduced.

Description

Technical Field

[0001] This invention belongs to the field of network security technology, specifically relating to a Byzantine Fault Tolerance (BFT) broadcast method and system in wireless networks. Background Technology

[0002] While the Byzantine fault-tolerant broadcast method has been widely used in traditional wired networks, it still faces many challenges in wireless networks. Wireless communication has become an indispensable part of modern society, and due to the openness and dynamism of wireless networks, they are also vulnerable to various security threats, such as malicious attacks, data tampering, and information leakage. Against this backdrop, the Byzantine fault-tolerant broadcast method has become a key technology for ensuring reliable communication in wireless networks, and it has significant application value in distributed systems and wireless sensor networks.

[0003] In traditional wired networks, Byzantine fault-tolerant broadcasting methods have individual connections between nodes, allowing direct communication between any two nodes. However, in wireless networks, direct communication between nodes is not possible. When the distance between two nodes exceeds their broadcast range, they cannot communicate directly. Applying existing wired network broadcasting methods to wireless networks cannot effectively achieve Byzantine fault-tolerant broadcasting in wireless networks.

[0004] To address the problem of unreliable broadcasting in wireless networks when Byzantine nodes are present, Vartika Bhandari and Nitin H. Vaidya proposed a broadcasting method for wireless networks in 2005. This method solves the Byzantine fault-tolerant broadcasting problem in wireless networks by having nodes rebroadcast received messages. The core idea of ​​this method is to achieve multiple message transmissions through cooperation between nodes, where each node rebroadcasts the received message to other nodes. Through multiple transmissions, nodes can receive a sufficient number of messages and determine the correct message by comparing and verifying these messages. However, this method faces some challenges in terms of communication complexity. Since nodes need to rebroadcast all received messages, the communication overhead increases significantly. This is a huge overhead for wireless networks because wireless channel resources are limited. Therefore, optimizing communication complexity while ensuring reliable broadcasting has become an important research direction.

[0005] Existing Byzantine fault-tolerant broadcast methods address the problem of unreliable broadcasting in wireless networks when Byzantine nodes are present, at the cost of high communication complexity. Designing a reliable and efficient Byzantine fault-tolerant broadcast method for wireless networks remains a pressing technical challenge. Summary of the Invention

[0006] In view of the above, the purpose of this invention is to provide a Byzantine fault-tolerant broadcast method and system in a wireless network, which can ensure communication quality while effectively reducing communication complexity.

[0007] To achieve the above-mentioned objectives, the present invention provides a Byzantine fault-tolerant broadcast method in a wireless network, comprising the following steps:

[0008] The source node broadcasts messages in the wireless network;

[0009] After receiving the first broadcast message from the source node in the current round, the neighboring nodes of the source node sign and authenticate the received first broadcast message before broadcasting the message.

[0010] After the source node's neighboring nodes collect the first broadcast message from the source node and all neighboring nodes in the current round, they generate a credential message for the collected first round of broadcast messages and broadcast the credential message.

[0011] After receiving the credential message, any node verifies and confirms the credential message before rebroadcasting it.

[0012] Preferably, in the Byzantine fault-tolerant broadcast method, the source node R s In a wireless network, a message broadcast is represented as: <COMMITTED,s,m,r,σ s > where m is the message content, s is the signer, r is the broadcast round, used to distinguish messages broadcast by the same source node in different rounds, and σ s σ represents the signature of the signer s on the message content. s =Sign(<s,m,r> ,pv s ), pv s For source node R s The private key, and Sign() is the signature function.

[0013] Preferably, in the Byzantine fault-tolerant broadcast method, the source node's neighbor node R i The first broadcast message received from the source node in the current round is <COMMITTED,s,m,r,σ s >;

[0014] After signing and authenticating the first received broadcast message, the message is broadcast, including: neighbor node R i right <COMMITTED,s,m,r,σ s >Verify signatureσ s Then, the message content m is confirmed, and the neighboring node R... i Sign the message content m to form a signature σ. i=Sign(<s,m,r> ,pv i After that, a broadcast message was sent. <COMMITTED,s,m,r,σ i >, where pv i For node R i The private key.

[0015] Preferably, in the Byzantine fault-tolerant broadcast method, the source node's neighbor node R i Collect the first broadcast message from the source node and all neighboring nodes in the current round. <COMMITTED,s,m,r,σ s >and <COMMITTED,s,m,r,σ i Afterwards, a credential message is generated for the first round of broadcast messages collected, including:

[0016] The aggregated signature is obtained by aggregating all signatures in the message. Aggre() is a signature aggregation function, {σ i} represents the set of signatures from f+1 messages, and simultaneously generates credential messages. in, r is the broadcast range for each node.

[0017] Preferably, in the Byzantine fault-tolerant broadcast method, any node can be the source node, neighboring nodes, and other nodes besides the source node and neighboring nodes. After receiving the credential message, any node verifies and confirms the credential message before rebroadcasting it, including:

[0018] Any node receives credential messages Verify aggregate signature After successfully confirming message content m, the credential message will be sent. To broadcast.

[0019] To achieve the above-mentioned objectives, the present invention also provides a Byzantine fault-tolerant broadcast system in a wireless network, including a source node, neighboring nodes of the source node, and other nodes besides the source node and its neighboring nodes.

[0020] The source node is used to broadcast messages in the wireless network;

[0021] The neighboring nodes of the source node are used to receive the first broadcast message from the source node in the current round, and then broadcast the message after signing and authenticating the first broadcast message received.

[0022] The neighboring nodes of the source node are used to collect the first broadcast message of the source node and all neighboring nodes in the current round, generate a credential message for the collected first round of broadcast messages, and broadcast the credential message.

[0023] Any node, including the source node, neighboring nodes, and other nodes, is used to receive the credential message, verify and confirm the credential message, and then rebroadcast the credential message.

[0024] Preferably, in a Byzantine fault-tolerant broadcast system, the source node R s In a wireless network, a message broadcast is represented as: <COMMITTED,s,m,r,σ s > where m is the message content, s is the signer, r is the broadcast round, used to distinguish messages broadcast by the same source node in different rounds, and σ s σ represents the signature of the signer s on the message content. s =Sign(<s,m,r> ,pv s ), pv s For source node R s The private key, and Sign() is the signature function.

[0025] Preferably, in a Byzantine fault-tolerant broadcast system, the source node's neighbor node R i The first broadcast message received from the source node in the current round is <COMMITTED,s,m,r,σ s >;

[0026] After signing and authenticating the first received broadcast message, the message is broadcast, including: neighbor node R i right <COMMITTED,s,m,r,σ s >Verify signatureσ s Then, the message content m is confirmed, and the neighboring node R... i Sign the message content m to form a signature σ. i =Sign(<s,m,r> ,pv i After that, a broadcast message was sent. <COMMITTED,s,m,r,σ i >, where pv i For node R i The private key.

[0027] Preferably, in a Byzantine fault-tolerant broadcast system, the source node's neighbor node R i Collect the first broadcast message from the source node and all neighboring nodes in the current round. <COMMITTED,s,m,r,σ s >and <COMMITTED,s,m,r,σ i Afterwards, a credential message is generated for the first round of broadcast messages collected, including:

[0028] The aggregated signature is obtained by aggregating all signatures in the message. Aggre() is a signature aggregation function, {σi} represents the set of signatures from f+1 messages, and simultaneously generates credential messages. in, r is the broadcast range for each node.

[0029] The Byzantine fault-tolerant broadcast method and system in a wireless network provided by this invention have at least the following beneficial effects:

[0030] Nodes do not need to rebroadcast all received messages. The source node's neighboring nodes only need to broadcast twice (once for COMMITTED and once for HEARED), while other nodes only need to broadcast once (for HEARED). The number of messages in the system is greatly reduced, effectively reducing communication complexity. Its implementation method is simple, not easy to make mistakes, and the code quality can be guaranteed. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 This is a flowchart of the Byzantine fault-tolerant broadcast method in a wireless network provided in the embodiment;

[0033] Figure 2 This is the processing flow provided in the embodiment when a neighboring node receives a message from the source node;

[0034] Figure 3 This is the aggregation processing of the signatures of the collected COMMITTED messages by the neighboring nodes provided in the embodiment;

[0035] Figure 4 This is the processing provided in the embodiment when any node receives a HEARED message. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the scope of protection of this invention.

[0037] This embodiment provides a Byzantine fault-tolerant broadcast method in a wireless network. The method is applied to a system with N×M nodes, each node located at a grid point in an N×M grid of 1×1 squares. Each node can be uniquely represented by its grid coordinates, for example, using R... (x,y) To represent a node at a grid point (x, y), R is used for simplicity when coordinate information is not important. k Nodes are represented by a public / private key pair. Each node possesses only its own private key but has access to the public keys of all other nodes. Each node's broadcast range is r (r ≤ N and r ≤ M). Nodes within this broadcast range are considered neighbors. A node and its neighbors form a neighborhood, and each neighborhood contains at most f Byzantine nodes. The distance between two nodes is measured using Chebyshev distance (corresponding to L...). ∞ Norm), two nodes R (x1,y1) and R (x2,y2) The distance between them is represented as d = max(|x1-x2|,|y1-y2|), and f needs to satisfy... For each node broadcasting a message, its neighboring nodes receive it in sequence. The nodes use the BLS (Boneh-Lynn-Shacham) signature algorithm to sign the message, thus achieving aggregate signature.

[0038] The Byzantine fault-tolerant broadcast method implemented based on the above system includes the following steps:

[0039] Step 1: The source node broadcasts a message in the wireless network.

[0040] In the system, source node R s To broadcast message content m, the broadcast message is... <COMMITTED,s,m,r,σ s >, where σ s This indicates a signature, with the subscript 's' indicating the signer and 'σ' indicating the signatory. s =Sign(<s,m,r> ,pv s Sign() is the signature function, pv s It is the source node R s The private key, r represents the round, used to distinguish messages broadcast from different rounds by the same source node.

[0041] Step 2: After receiving the first broadcast message from the source node in the current round, the neighboring nodes of the source node sign and authenticate the first broadcast message before broadcasting the message.

[0042] Neighbor node R i Received the first message broadcast in round r in step 1 <COMMITTED,s,m,r,σ s When >, neighbor node Ri Using R s public key pb s Verify signature σ s Then, the message content m is confirmed. Simultaneously, neighboring node R... i Broadcast the message after signing it. <COMMITTED,s,m,r,σ i >, where σ i =Sign(<s,m,r> ,pv i Here, the neighbor node R i Use your own private key PV i For the same message<s,m,r> Signed, such as Figure 2 As shown.

[0043] Step 3: After collecting the first broadcast message of the source node and all neighboring nodes in the current round, the neighboring nodes of the source node generate a credential message for the collected first round of broadcast messages and broadcast the credential message.

[0044] Neighbor node R i The first COMMITTED message broadcast by the source node and neighbor nodes in round r during steps 1 and 2 (i.e., including...) <COMMITTED,s,m,r,σ s >and <COMMITTED,s,m,r,σ i >) Collect data from neighboring node R i Generate a credential message that proves the validity and credibility of the message based on the signature carried by the collected message, and broadcast the credential message.

[0045] Specifically, when neighbor node R i When a neighboring node R receives a COMMITTED message from f+1 different nodes in round r, i These signatures are aggregated to form an aggregate signature. {σ i Let f be the set of signatures for f+1 distinct COMMITTED messages, Aggre() be the signature aggregation function, and neighbor node R be the set of signatures. i Obtain aggregate signature The voucher message is then generated. And broadcast, such as Figure 3 As shown.

[0046] Step 4: After receiving the credential message, any node verifies and confirms the credential message before rebroadcasting it.

[0047] If any node R j The first time the neighbor node R in step 4 is received i broadcast credential messages This credential message can be sent directly from neighboring node R. i Broadcast or broadcast by other nodes, any node R j After verifying its aggregate signature, the message content m is confirmed, and the credential message is verified. To broadcast, such as Figure 4 As shown.

[0048] In the Byzantine fault-tolerant broadcasting method described above, nodes do not need to rebroadcast all received messages. The neighboring nodes of the source node only need to broadcast twice (once for COMMITTED and once for HEARED), while other nodes only need to broadcast once (for HEARED). The number of messages in the system is greatly reduced, effectively reducing communication complexity. Its implementation method is simple, not easy to make mistakes, and the code quality can be guaranteed.

[0049] The specific embodiments described above illustrate the technical solution and beneficial effects of the present invention in detail. It should be understood that the above description is only the most preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, additions, and equivalent substitutions made within the scope of the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A Byzantine fault-tolerant broadcast method in a wireless network, characterized in that, Includes the following steps: The source node broadcasts messages in the wireless network; After receiving the first broadcast message from the source node in the current round, the neighboring nodes of the source node perform signature authentication on the received first broadcast message before broadcasting the message. The signature authentication uses the signature function Sign(). After the source node's neighboring nodes collect the first broadcast message from the source node and all neighboring nodes in the current round, they generate a credential message for the collected first round of broadcast messages and broadcast the credential message, which includes: aggregating all signatures in the message to obtain an aggregated signature. =Aggre({σ i Aggre() is the signature aggregation function, {σ} i }for The set of signatures in each message, and simultaneously generate credential messages. ,in, , r The broadcast range for each node, f The number of Byzantine nodes is m, the message content is s, the signer is r, and the broadcast round is r, which is used to distinguish messages broadcast by the same source node in different rounds. After receiving the credential message, any node verifies and confirms the credential message before rebroadcasting it.

2. The Byzantine fault-tolerant broadcast method in a wireless network according to claim 1, characterized in that, Source node R s In a wireless network, a message broadcast is represented as: , where σ s This indicates that the signer 's' has signed the message content. ,pv s For source node R s The private key, and Sign() is the signature function.

3. The Byzantine fault-tolerant broadcast method in a wireless network according to claim 2, characterized in that, The neighbor node R of the source node i The first broadcast message received from the source node in the current round is ; After signing and authenticating the first received broadcast message, the message is broadcast, including: neighbor node R i right Verify signature σ s Then, the message content m is confirmed, and the neighboring node R... i Sign the message content m to form a signature. Afterwards, a broadcast message Among them, pv i For node R i The private key.

4. The Byzantine fault-tolerant broadcast method in a wireless network according to claim 1, characterized in that, Any node can be the source node, neighboring nodes, and other nodes besides the source node and neighboring nodes. After receiving the credential message, any node verifies and confirms the credential message before rebroadcasting it, including: Any node receives credential messages Verify aggregate signature After successfully confirming message content m, the credential message will be sent. To broadcast.

5. A Byzantine fault-tolerant broadcast system in a wireless network, characterized in that, This includes the source node, the source node's neighboring nodes, and all other nodes besides the source node and its neighboring nodes. The source node is used to broadcast messages in the wireless network; The neighboring nodes of the source node are used to receive the first broadcast message from the source node in the current round, perform signature authentication on the received first broadcast message, and then broadcast the message. The signature authentication uses the signature function Sign(). The source node's neighboring nodes are used to collect the first broadcast message from the source node and all neighboring nodes in the current round, generate a credential message for the collected first round of broadcast messages, and broadcast the credential message, including: aggregating all signatures in the message to obtain an aggregated signature. =Aggre({σ i Aggre() is the signature aggregation function, {σ} i }for The set of signatures in each message, and simultaneously generate credential messages. ,in, , r The broadcast range for each node, f The number of Byzantine nodes is m, the message content is s, the signer is r, and the broadcast round is r, which is used to distinguish messages broadcast by the same source node in different rounds. Any node, including the source node, neighboring nodes, and other nodes, is used to receive the credential message, verify and confirm the credential message, and then rebroadcast the credential message.

6. The Byzantine fault-tolerant broadcast system in a wireless network according to claim 5, characterized in that, Source node R s In a wireless network, a message broadcast is represented as: , where σ s This indicates that the signer 's' has signed the message content. ,pv s For source node R s The private key, and Sign() is the signature function.

7. The Byzantine fault-tolerant broadcast system in a wireless network according to claim 6, characterized in that, The neighbor node R of the source node i The first broadcast message received from the source node in the current round is ; After signing and authenticating the first received broadcast message, the message is broadcast, including: neighbor node R i right Verify signature σ s Then, the message content m is confirmed, and the neighboring node R... i Sign the message content m to form a signature. Afterwards, a broadcast message Among them, pv i For node R i The private key.

Images