KR102263461B1 - Method and apparatus for multicasting block data based on scalable peer to peer overlay structure - Google Patents

Abstract

The present invention relates to a block data multicasting method based on an expandable P2P (peer to peer) overlay structure, which is executed by a mobile edge clouding (MEC) server. The method includes the following steps of: receiving a request for a transaction proposal from a user terminal; transmitting the transaction proposal to at least one endorsing mobile peer; receiving guarantee information including smart contract execution information and signature information in accordance with the transaction proposal from the at least one endorsing mobile peer; generating a transaction based on the guarantee information; generating block information based on the transaction; spreading the block information to a plurality of mobile peers including the endorsing mobile peer in accordance with pre-constituted overlay structure; receiving notification information verified and committed with respect to the block information from the plurality of mobile peers; and transmitting response information indicating that the transaction proposal has been processed to the user terminal based on the notification information.

Description

Block data multicasting method and apparatus based on scalable P2P overlay structure {METHOD AND APPARATUS FOR MULTICASTING BLOCK DATA BASED ON SCALABLE PEER TO PEER OVERLAY STRUCTURE}

The present invention relates to a block data multicasting method and apparatus based on a scalable peer to peer (P2P) overlay structure, and more particularly, to a real-time service in a 5G network environment by utilizing MEC (mobile edge computing) technology and D2D technology. It relates to a peer-to-peer overlay multicast system for a suitable blockchain platform.

Recently, blockchain has been attracting attention as the basis for cryptocurrencies such as Bitcoin. It represents a decentralized digital ledger made up of records called blocks that are used to record the transactions of many users. Blockchain technology has four main functions: transparency, reliability, efficiency, control and security, and every block in the ledger is characterized by being immutable retroactively without altering all subsequent blocks. Blockchain platforms that leverage these blockchain technologies can register assets, validate transactions, manage interactions, and provide a trusted, decentralized and secure way for many industries such as energy, healthcare, insurance, transportation and entertainment. It is increasingly used to record data.

However, although blockchain has the above promising functions, its practical application is limited due to scalability problems such as storage and throughput. In particular, the transaction throughput, that is, the transaction confirmation latency, has not reached a satisfactory level compared to existing centralized services such as the VISA system, which can process 2,000 transactions per second. For example, in blockchain, the gossip protocol has been widely adopted to propagate newly created blocks to all peers. However, the random selection mechanism of the gossip protocol has a problem in that data duplication frequently occurs, resulting in significant block propagation delay. Here, block propagation delay is one of the most important factors closely related to the transaction throughput of a blockchain network. This block propagation delay can lead to inconsistencies between peers' ledger information, resulting in a high rate of stale blocks and blockchain forks. Also, in this case, a double payment problem may arise. Thus, transaction throughput is limited to prevent an adversarial user from attempting a double-spending attack. Recently, several studies have been conducted to overcome the scalability problem in terms of transaction throughput.

In addition, with the recent advent of 5G networks, which are about 20 times faster than 4G networks, mobile edge computing (MEC) is a technology that can meet sophisticated requirements for real-time services such as connected cars and autonomous driving. It is receiving considerable attention as a potential solution. With abundant computing, storage and networking resources, MEC servers can be located at the edge of a radio access network (RAN) to develop intelligent, latency-sensitive, context-aware applications. In recent years, the integration of blockchain platforms and 5G network infrastructure has attracted tremendous attention as a potential solution for flexible and secure 5G edge services, and various studies are being conducted.

However, according to past studies, new business models can be created by utilizing the mutual benefits and complementary relationships between blockchain and 5G, but the slow transaction processing speed of blockchain networks is still a big challenge when applied to real-time services. Many consensus mechanisms, such as proof of work (PoW), proof of stake (PoS), and directed acyclic graph (DAG), cause significant delays, so despite great features such as stability and transparency And there is a problem that makes the blockchain platform impractical. Therefore, it is a major and urgent issue to design a new blockchain architecture suitable for real-time services while overcoming the inherent scalability problems of the current blockchain.

An object of the present invention to solve the above problems is to provide a block data multicasting method based on an expandable P2P overlay structure.

Another object of the present invention to solve the above problems is to provide a block data multicasting apparatus based on an expandable P2P overlay structure.

A block data multicasting method based on a scalable peer to peer (P2P) overlay structure performed in a mobile edge clouding (MEC) server according to an embodiment of the present invention for achieving the above object is a request for a transaction proposal from a user terminal. receiving, sending the transaction proposal to at least one endorsing mobile peer; guarantee information including smart contract execution information and signature information according to the transaction proposal from the at least one indoling mobile peer receiving, generating a transaction based on the guarantee information, generating block information based on the transaction, and transmitting the block information according to a pre-configured overlay structure to a plurality of mobiles including the mobile peer. Propagating to peers, receiving notification information on which verification and committing of the block information have been performed from the plurality of mobile peers, and response information indicating that the transaction proposal has been processed to the user terminal based on the notification information may include the step of transmitting

Here, the overlay structure is configured based on a peer selection table, and the peer selection table may be updated by receiving network state information and information on other adjacent mobile peers from each of the plurality of mobile peers.

Here, the overlay structure may be configured based on block transmission delay time information of each of the plurality of mobile peers, and the block transmission delay time information may be included in the network state information.

Here, the plurality of mobile peers include at least some first mobile peers included in a cellular network peer group and the remaining second mobile peers included in a device to device (D2D) network peer group, and the first mobile peers may receive the block information from the MEC server through a cellular network, and the second mobile peer may receive the block information from a neighboring mobile peer among the at least some first mobile peers through a D2D network.

Here, in the case of the first mobile peer, the block delay time information is derived based on the size of the block information and the data rate from the MEC server to the first mobile peer, and in the case of the second mobile peer, block information It can be derived based on the size of , and the data rate from the neighboring mobile peer to the second mobile peer.

A mobile edge clouding (MEC) server performing a block data multicasting method based on an extensible peer to peer (P2P) overlay structure according to an embodiment of the present invention for achieving the above other object is a processor and the processor at least one command executed through a memory stored therein, wherein the at least one command is executed to receive a request for a transaction proposal from a user terminal, and transmits the transaction proposal to at least one endorsing mobile peer and execute to transmit, receive from the at least one indoling mobile peer, endorsement information including smart contract execution information and signature information according to the transaction proposal, and generate a transaction based on the endorsement information; and to generate block information based on the transaction, and to propagate the block information to a plurality of mobile peers including the indoling mobile peer according to a preconfigured overlay structure, from the plurality of mobile peers It may be executed to receive notification information on which verification and commit of block information have been performed, and to transmit response information indicating that the transaction proposal has been processed to the user terminal based on the notification information.

Here, the overlay structure is configured based on a peer selection table, and the peer selection table may be updated by receiving network state information and information on other adjacent mobile peers from each of the plurality of mobile peers.

Here, the overlay structure may be configured based on block transmission delay time information of each of the plurality of mobile peers, and the block transmission delay time information may be included in the network state information.

Here, the plurality of mobile peers include at least some first mobile peers included in a cellular network peer group and the remaining second mobile peers included in a device to device (D2D) network peer group, and the first mobile peers may receive the block information from the MEC server through a cellular network, and the second mobile peer may receive the block information from a neighboring mobile peer among the at least some first mobile peers through a D2D network.

Here, in the case of the first mobile peer, the block delay time information is derived based on the size of the block information and the data rate from the MEC server to the first mobile peer, and in the case of the second mobile peer, block information It can be derived based on the size of , and the data rate from the neighboring mobile peer to the second mobile peer.

According to the present invention, by integrating a blockchain platform into a mobile edge computing (MEC) architecture, it is possible to alleviate the propagation delay of block data and improve the transaction throughput.

According to the present invention, compute- and bandwidth-intensive tasks such as consensus and assurance are offloaded to the MEC server, thereby reducing block propagation delay as well as easing the burden of large-scale resource consumption tasks on mobile peers.

According to the present invention, it is possible to quickly complete block propagation to all mobile peers by configuring a peer-to-peer (P2P) overlay structure for a blockchain platform suitable for 5G real-time service.

According to the present invention, even a mobile peer having a poor cellular network condition can receive block data by establishing a device to device (D2D) connection with a neighboring mobile peer.

According to the present invention, we design a new 5G blockchain architecture that is compatible with the blockchain platform, operating as one container on MEC and mobile devices, all containers with very low time complexity will interact closely with other containers on the blockchain platform. can

1 is a diagram showing a transaction flow of a hyperledger-fabric blockchain.
2 is a diagram illustrating the structure of a D2D support scalable P2P multicast system according to an embodiment of the present invention.
3 is a flowchart illustrating an interaction procedure between containers according to an embodiment of the present invention.
4 to 7 are diagrams illustrating four block propagation scenarios according to an embodiment of the present invention.
8 is a diagram illustrating an overlay multicast structure for block propagation according to an embodiment of the present invention.
9 is a diagram illustrating a mobile peer grouping algorithm according to an embodiment of the present invention.
10 is a block diagram of a block data multicasting apparatus based on a scalable P2P overlay structure according to an embodiment of the present invention.
11 is a flowchart of a block data multicasting method based on a scalable P2P overlay structure according to an embodiment of the present invention.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention. In describing each figure, like reference numerals have been used for like elements.

Terms such as first, second, A, and B may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. The term “and/or” includes a combination of a plurality of related listed items or any of a plurality of related listed items.

When a component is referred to as being “connected” or “connected” to another component, it is understood that the other component may be directly connected or connected to the other component, but other components may exist in between. it should be On the other hand, when it is mentioned that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. In describing the present invention, in order to facilitate the overall understanding, the same reference numerals are used for the same components in the drawings, and duplicate descriptions of the same components are omitted.

An embodiment of the present invention proposes a scalable peer to peer (P2P) overlay multi-cast system for a blockchain platform suitable for 5G real-time service. In the system according to an embodiment, mobile edge computing (MEC) may be utilized to rapidly process a transaction proposal and propagate block data by utilizing abundant computing and storage resources. In addition, the system according to an embodiment may use a fast and lightweight consensus algorithm that is more suitable for real-time services based on a hyperledger-fabric blockchain platform, which is one of the blockchain platforms.

A description related to a hyperledger-fabric blockchain platform according to an embodiment of the present invention will be described later with FIG. 1, and a description related to a D2D support scalable P2P overlay multicast system will be described later with FIGS. 2 to 9.

1 is a diagram showing a transaction flow of a hyperledger-fabric blockchain.

Hyperledger-fabric is an open-source, enterprise-grade licensed distributed ledger platform founded by the Linux Foundation. Fabrics can have a modular and configurable architecture that enables innovation, versatility and optimization for a wide range of industrial applications including manufacturing, banking, logistics, healthcare and human resources. Chaincode, called smart contracts in Fabric, can be written using a general-purpose programming language rather than a restricted domain-specific language. Fabric can be classified as a class of permissioned blockchain platforms where blockchain network participants know each other. Thus, the Fabric blockchain network can operate under a governance model built on trust between participants. As a modular architecture, Fabric supports pluggable consensus to efficiently synchronize all ledgers on a blockchain network. Thus, the consensus protocol can be customized for industrial applications. In general, Fabric can utilize a more feasible consensus protocol that does not require mining based on trust between permissioned blockchain participants. Unlike the order-execute architecture adopted by most blockchain platforms, Fabric follows the execute-order-validate phase of a transaction for resiliency, flexibility, and scalability. It can solve the problems of scalability, performance and confidentiality.

Referring to FIG. 1 , in the execute phase, the smart contract may be executed, and a transaction proposal to the client may be sent to some peers called endorsing peers to ensure accuracy, and the execution result of the smart contract And one transaction can be created with the signature of the indoling peer. In the order stage, transactions may be ordered on a first-come-first-served basis and packaged into blocks. In the validate phase, all transactions in a block can be validated to ensure that they are consistently guaranteed by the indoling peer before being committed to the ledger. Transactions that fail validation may not be committed to the ledger. Here, commit refers to an operation requesting the end when it is determined that all operations included in one transaction are executed, the database update is recorded in the work area (storage device), and the application of the transaction is determined to be completed. can

Fabric blockchain network can consist of multiple nodes, and each node can be classified into four types according to their role.

1. Client software development kit (SDK): SDK is a type of web server that provides clients with access to smart contracts and ledgers. With SDK, applications call smart contracts to create transactions, You can submit a transaction to the orderer and be notified when the run-order-verify phase is complete.

2. Fabric certificate authority (CA): A CA can issue X.509 certificates to all nodes participating in the blockchain network. Here, a certificate can be used to sign a transaction and vouch for the outcome of the transaction.

3. Orderer: The orderer can set the order of all transactions. They may communicate with each other by forming clusters to determine the order, and may not be involved in the execution and validation phases.

4. Peer: A peer can be classified into several categories, such as a committing peer, a leader peer, and an endorsing peer, according to roles. Any peer can act as a commit peer that validates blocks and commits them to the ledger. The leader peer may be the only node distributing blocks from the orderer to other commit peers. An indoling peer may be a node that hosts a smart contract and guarantees execution results. In actual application, only a small number of peers can perform the role of indoling peers in consideration of the workload of the blockchain network.

2 is a diagram illustrating the structure of a D2D support scalable P2P multicast system according to an embodiment of the present invention.

A system according to an embodiment is to provide a blockchain platform with high transaction throughput by configuring an overlay structure so that the overall block propagation delay is minimized. However, a mobile device having limited resources may have difficulty in performing a computation-intensive consensus operation. Therefore, existing blockchain platforms with complex mining processes may not be suitable for real-time 5G services, and applying permissioned blockchain flatbom such as Hyperledger-Fabric, which performs faster and more scalable consensus, is not recommended. can be justified

A system according to an embodiment is a crowd-sensing and crowd-sourced system in which mobile nodes with a common interest located in the same cell coverage collect and share data such as temperature, humidity and air quality. sourcing) can be considered. In this environment, adjacent mobile nodes may contact each other through device to device (D2D) communication.

A system according to an embodiment may have a structure as shown in FIG. 2 . Referring to FIG. 2 , in the system according to an embodiment, mobile nodes may be classified into two types. Here, the two types can be mobile peers and mobile users, where mobile users can only enjoy blockchain-based 5G services, but mobile peers can be responsible for validating the blockchain network with their own ledger.

The overlay multicast system according to an embodiment may be configured with MEC and mobile peers having dual interfaces. Here, the dual interface may include a 5G wireless interface and a WiFi interface. A mobile peer with two interfaces can receive block data from the gNB or neighboring mobile peers. Here, gNB may represent a 5G base station.

In the system according to an embodiment, computation-intensive functions of the fabric blockchain platform may be offloaded to the MEC in consideration of the flexibility and scalability of the blockchain network. However, monitoring tasks such as validation and endorsement can be distributed to mobile peers to actively audit the MEC and improve the reliability of the blockchain network.

For example, the MEC may include 5 main containers. Here, the five main containers may include a software defined network (SDN) container and four containers related to the fabric (fabric CA, orderer, leader peer, and client SDK). The SDN server container may obtain network information such as D2D network status from cellular and mobile peers. Based on this information, the SDN server can recognize the network topology composed of mobile peers. Through the network topology, the overlay constructor, which is one of the modules of the SDN server, calculates the optimal path to complete block propagation in the shortest time, and provides information of neighboring peers to each mobile peer. can be sent.

For example, each of the mobile peers may include two main containers. Here, the two containers may include an SDN client and a peer container related to the fabric. The SDN client container may be composed of three modules including a network manager, a forwarding information receiver, and a communication. The network manager module may periodically record a cellular channel state based on a CSI (channel state information) signal. In addition, if a mobile peer that can be contacted through direct communication exists nearby, information such as peer identification and network signal strength (information of nearby mobile peers) can be sent to the SDN server container of the MEC. . A network between an SDN server and a client in a system according to an embodiment

Working may be performed through google remote procedure call (GRPC)-based communication. All data transmitted in GRPC communication may be encrypted based on transport layer security (TLS). The forwarding information receiver module may periodically obtain information of neighboring peers from the SDN server container for block propagation. The peer container may record the above information of neighboring peers in a peer selection table. Thereafter, whenever block data is received, block data may be delivered to neighboring peers based on the table.

3 is a flowchart illustrating an interaction procedure between containers according to an embodiment of the present invention.

Referring to FIG. 3 , the overall operation procedure according to an embodiment may be divided into two procedures that do not occur simultaneously (asynchronous). Here, the two procedures may include an overlay construction procedure and a fabric blockchain procedure.

In the overlay configuration procedure, the SDN client container of the mobile peer may report the network status to the SDN server container whenever a noticeable change in the network status is detected. The SDN server may collect all network information from mobile peers, and send neighboring peer information to each mobile peer. The peer selection table of the peer container of the mobile peer may be updated based on this information. As a result, the updated table information may affect the block propagation sequence of fabric blockchain network procedures, which are procedures that do not occur simultaneously.

In the fabric blockchain network procedure, mobile users can only access the blockchain ledger through the SDK container. Accordingly, the user terminal may transmit a transaction proposal request to the SDK container of the MEC. Whenever it receives a request from a user terminal, the SDK container may forward it to some mobile peers called indoling mobile peers. The indoling mobile peer can execute the smart contract according to the transaction proposal and return the execution result along with the signature. Here, the returned signature and execution result (read/write set) may be expressed as endorsement or endorsement information.

The SDK container can create a transaction with endorsements collected from the indoling mobile peer and then forward it to the orderer container located on the same host machine, the MEC. The orderer container can arrange a batch of transactions delivered from the SDK container into a well-defined sequence and package it into a block. That is, blocks can be created.

Each time a new block is created from the orderer container, the leader peer container can take it and distribute it to neighboring mobile peers recorded in the peer selection table. When the mobile peer receives the block data, after transmitting it to the neighboring mobile peer, the mobile peer may validate each transaction of the block to confirm that all transactions are guaranteed by the indoling mobile peers. Mobile peers can commit transactions and update the ledger once all transactions in the immutable block are properly endorsed. That is, peer containers of mobile peers may send a notification to the SDK container of the MEC after verifying and committing the received block. The SDK container can confirm the user's transaction when the block is committed by mobile peers, and reply to the user with a confirmation message.

Hereinafter, the problem of constructing an overlay structure for fast block propagation will be described in detail along with all possible block propagation scenarios in a service environment.

4 to 7 are diagrams illustrating four block propagation scenarios according to an embodiment of the present invention.

4 may show a scenario for cellular multicast (evolved multimedia broadcast multicast service, eMBMS). The eMBMS may be an effective transmission method when the MEC transmits the same data block to mobile peers with spatial and temporal locality. However, the receivable data rate of all mobile peers may be limited by the mobile peer with weak signal strength in the multicast group.

5 may show a scenario for cellular unicast. The advantage of the unicast transmission method is that the transmission rate can be adjusted according to the cellular network status of each mobile peer. However, the unicast transmission method may inefficiently use radio network resources when the MEC transmits the same data block to several mobile peers within the same cell.

6 and 7 may show scenarios for cellular multicast and unicast extended by device to device communication. In this way, the network range can be extended and the performance of the cellular network can be improved. In this case, the MEC transmits data blocks to some mobile peers with good channel conditions in the cellular network, and other mobile peers transmit data blocks from adjacent mobile nodes (some mobile peers that have received the data block) through D2D communication. can receive

및

는 각각 MEC에서 i번째 모바일 피어로의 블록 데이터 크기 및 데이터 속도를 나타낼 수 있다. 여기서, i는 자연수 중 하나를 나타낼 수 있다. 따라서 i번째 모바일 피어가 MEC로부터 블록 데이터를 직접 수신하는 데 걸리는 시간, 즉 블록 전송 지연 시간은 수학식 1과 같이 산출될 수 있다.Some symbols may be defined as follows to specify the overlay structure configuration problem.

and

may represent the block data size and data rate from the MEC to the i-th mobile peer, respectively. Here, i may represent one of natural numbers. Accordingly, the time it takes for the i-th mobile peer to directly receive block data from the MEC, that is, the block transmission delay time, can be calculated as in Equation 1.

는 MEC에서 i번째 모바일 피어로의 블록 전송 지연 시간을 나타낼 수 있다. 여기서,

은 네트워크 시스템 파라미터, 즉 변조 차수(modulation), 수비학(numerology) 및 OFDM 심볼 기간(orthogonal frequency division multiplexing symbol duration)가 주어지면 모바일 장치에 할당된 자원 블록들의 수를 기반으로 쉽게 산출될 수 있다. In Equation 1,

may represent the block transmission delay time from the MEC to the i-th mobile peer. here,

Can be easily calculated based on the number of resource blocks allocated to the mobile device given the network system parameters, that is, modulation order, numerology, and OFDM symbol duration (orthogonal frequency division multiplexing symbol duration).

In cellular multicast/unicast extended by D2D, the i-th mobile peer can receive blocks from its adjacent j-th mobile peer via D2D communication. Here, j may represent one different from i among natural numbers. In this case, the block transmission delay time from the adjacent j-th mobile peer to the i-th mobile peer may be calculated as shown in Equation (2).

는 i번째 모바일 피어에서 j번째 모바일 피어로의 블록 전송 지연 시간을 나타낼 수 있다.

은 i번째 모바일 피어에서 j번째 모바일 피어까지의 데이터 속도를 나타낼 수 있으며, 수신 신호 강도 표시(RSSI: received signal strength indication)를 이용하여 측정될 수 있다.In Equation 2,

may represent the block transmission delay time from the i-th mobile peer to the j-th mobile peer.

may indicate the data rate from the i-th mobile peer to the j-th mobile peer, and may be measured using a received signal strength indication (RSSI).

8 is a diagram illustrating an overlay multicast structure for block propagation according to an embodiment of the present invention.

Referring to FIG. 8 , the tree-based overlay structure may be organized into two levels. The weight of edges between the root and the first level may indicate a block transmission time through the cellular network, and the weight of the edges between the first level and the second level may indicate a block transmission time through the D2D network. can indicate time. Here, each of the root, the first level, and the second level represents three rows of FIG. 8 in order from top to bottom.

Now, if the overlay structure configuration problem is formulated as follows, it can be expressed as Equation (3).

는 미리 주어진 전체 모바일 피어 세트를 나타낼 수 있고,

및

는 셀룰러 네트워크 피어 그룹 및 D2D 네트워크 피어 그룹을 나타낼 수 있다. 또한,

은 수학식 1에서와 같이 셀롤러 네트워크를 통해 MEC으로부터 i번째 모바일 피어로의 블록 전송 지연 시간을 나타낼 수 있고,

는 수학식 2에서와 같이 D2D 네트워크를 통해 i번째 모바일 피어로부터 j번째 모바일 피어로의 블록 전송 지연 시간을 나타낼 수 있다. 즉, 수학식 3에서 max{}의 내부는 MEC으로부터 j번째 모바일 피어로로의 블록 전송 지연 시간으로 볼 수 있으며, f는 모든 i 및 j에 대하여 MEC으로부터 j번째 모바일 피어로까지의 블록 전송 지연 시간 중 가장 큰 경우를 나타낼 수 있다. In Equation 3,

may represent the pre-given full set of mobile peers,

and

may represent a cellular network peer group and a D2D network peer group. Also,

may represent the block transmission delay time from the MEC to the i-th mobile peer through the cellular network as in Equation 1,

may represent the block transmission delay time from the i-th mobile peer to the j-th mobile peer through the D2D network as in Equation 2 . That is, the inside of max{} in Equation 3 can be seen as the block transmission delay time from the MEC to the j-th mobile peer, and f is the block transmission delay from the MEC to the j-th mobile peer for all i and j. It can represent the largest case of time.

, 네트워크 토폴로지 및 모든 모바일 피어에 대한 네트워크 상태를 고려하여 셀룰러 네트워크 피어 그룹

및 D2D 네트워크 피어 그룹

를 결정하는 것이다.The purpose of the overlay architecture configuration problem according to one embodiment is to minimize the overall block propagation delay given a full set of mobile peers in advance.

, a group of cellular network peers, taking into account the network topology and the network state for all mobile peers.

and D2D network peer group

is to determine

내의 각 모바일 피어들을 셀룰러 네트워크 피어 그룹

또는 D2D 네트워크 피어 그룹

으로 할당할 수 있다. 다시 말해, 수학식 3의 문제는 최근 블록을 수신한 모바일 피어에 대한 블록 수신 시간을 최소화하는 것일 수 있다. 일 실시에는 이를 위해 후술하는 모바일 피어 그룹핑 알고리즘을 이용할 수 있다.Thus, one embodiment is a pre-given full set of mobile peers such that f is minimized in equation (3).

Each mobile peer within a cellular network peer group

or D2D network peer group

can be assigned as In other words, the problem of Equation 3 may be to minimize the block reception time for the mobile peer that has recently received the block. In one embodiment, a mobile peer grouping algorithm described later may be used for this purpose.

9 is a diagram illustrating a mobile peer grouping algorithm according to an embodiment of the present invention.

및

를 결정하는 방법에 대하여 설명하겠다. 오버레이 구조 구성 문제에서

및

의 결정 프로세스는 그래프 토폴로지의 하나의 특정 정점(vertex)에서 다른 모든 정점들까지 최단 경로를 결정하는 잘 알려진 최단 경로 문제로 간주될 수 있다. 또한, 오버레이 구조 구성 문제는 하나의 MEC에서 모든 모바일 피어들까지의 최단 경로를 결정하는 것으로 생각할 수도 있습니다. 유향의(directed) 그래프 토폴로지에서 시작하는 정점을 제외한 나머지 정점들 및 엣지들의 각 가중치는 각각 모바일 피어들 및 각 모바일 피어의 블록 수신 시간으로 해석될 수 있다.Hereinafter, with reference to FIG. 9, the control variable

and

We will explain how to determine In the overlay structure configuration problem

and

The decision process of n can be considered as the well-known shortest path problem of determining the shortest path from one specific vertex to all other vertices of the graph topology. Also, the problem of constructing an overlay structure can be thought of as determining the shortest path from one MEC to all mobile peers. Each weight of vertices and edges other than a vertex starting in a directed graph topology may be interpreted as mobile peers and block reception times of each mobile peer, respectively.

의 합리적인 계산 복잡도를 가진 최적의 솔루션을 얻기 위해 Dijkstra의 알고리즘을 이용할 수 있다. 모든 모바일 피어들에 대한

및

의 전체 결정 프로세스는 도 9의 모바일 피어 그룹핑 알고리즘에서 설명될 수 있다.Therefore, one embodiment

Dijkstra's algorithm can be used to obtain an optimal solution with a reasonable computational complexity of . for all mobile peers

and

The entire determination process of ? can be described in the mobile peer grouping algorithm of FIG. 9 .

For example, referring to FIG. 9 , a vortex may correspond to a mobile peer, and in one embodiment, the MEC is set as the first vortex, and the i-th vortex (mobile peer) belonging to the entire mobile peer group is selected, If the previous vortex of the selected i-th vortex is the first vortex, it is considered that the data block is received from the MEC through the cellular network, so the i-th vortex can be included in the cellular network peer group, and the previous vortex of the selected i-th vortex If is not the first vortex, it is considered that a data block has been received from another vortex (another adjacent mobile peer) through the D2D network, and thus the i-th vertex may be included in the D2D network peer group.

10 is a block diagram of a block data multicasting apparatus based on a scalable P2P overlay structure according to an embodiment of the present invention.

Referring to FIG. 10 , the block data multicasting apparatus 1000 based on the scalable P2P overlay structure according to an embodiment of the present invention includes at least one processor 1010 , a memory 1020 , and a storage device 1030 . can do. Also, although not shown in FIG. 10 , the block data multicasting apparatus 1000 based on the expandable P2P overlay structure may include a communication module capable of cellular communication. For example, cellular communication may refer to 5G communication, but may also include other communication such as 4G and the like. Here, the block data multicasting apparatus 1000 based on the scalable P2P overlay structure may represent an MEC server.

The processor 1010 may execute a program command stored in the memory 1020 and/or the storage device 1030 . The processor 1010 may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to the present invention are performed. The memory 1020 and the storage device 1030 may be configured of a volatile storage medium and/or a non-volatile storage medium. For example, the memory 1020 may be configured as a read only memory (ROM) and/or a random access memory (RAM).

The memory 1020 may store at least one instruction executed through the processor 1010 . The at least one instruction includes an instruction for receiving a request for a transaction proposal from a user terminal, an instruction for sending the transaction proposal to at least one endorsing mobile peer, and an instruction to receive the transaction proposal from the at least one indoling mobile peer. A command for receiving guarantee information including smart contract execution information and signature information according to a command, a command for generating a transaction based on the guarantee information, a command for generating block information based on the transaction, and an instruction for generating block information based on the transaction, the block according to a preconfigured overlay structure Based on a command for propagating information to a plurality of mobile peers including the indoling mobile peer, a command for receiving notification information on which verification and committing of the block information has been performed from the plurality of mobile peers, and the notification information may include a command for transmitting response information indicating that the transaction proposal has been processed to the user terminal.

For example, the overlay structure may be configured based on a peer selection table, and the peer selection table may be updated by receiving network state information and information on other adjacent mobile peers from each of the plurality of mobile peers. .

For example, the overlay structure may be configured based on block transmission delay time information of each of the plurality of mobile peers, and the block transmission delay time information may be included in the network state information.

For example, the plurality of mobile peers may include at least some first mobile peers included in a cellular network peer group and the remaining second mobile peers included in a device to device (D2D) network peer group, and A first mobile peer may receive the block information from the MEC server via a cellular network, and the second mobile peer may receive the block information from a neighboring mobile peer among the at least some first mobile peers via a D2D network. can receive

For example, the block delay time information may be derived based on a size of block information and a data rate from the MEC server to the first mobile peer in the case of the first mobile peer, and case, it may be derived based on the size of the block information and the data rate from the adjacent mobile peer to the second mobile peer.

11 is a flowchart of a block data multicasting method based on a scalable P2P overlay structure according to an embodiment of the present invention.

Referring to FIG. 11 , according to an embodiment, a request for a transaction proposal may be received from a user terminal ( S1110 ), and the transaction proposal may be transmitted to at least one endorsing mobile peer ( S1120 ). Here, the indoling mobile peer may represent a node that hosts a smart contract among mobile peers and guarantees an execution result.

According to an embodiment, guarantee information including smart contract execution information and signature information according to the transaction proposal may be received from the at least one indoling mobile peer (S1130). That is, the indoling mobile peer can execute the smart contract according to the transaction proposal and return the execution result along with the signature. Here, the returned signature and execution result (read/write set) may be expressed as endorsement or endorsement information.

According to an embodiment, a transaction may be generated based on the guarantee information (S1140), and block information may be generated based on the transaction (S1150). Here, according to an embodiment, the orderer container may arrange a batch of transactions into a well-defined sequence and package it into a block, ie, generate a block.

Thereafter, an embodiment may propagate the block information to a plurality of mobile peers including the indoling mobile peer according to a preconfigured overlay structure ( S1160 ). Here, the overlay structure may be configured based on a peer selection table, and the peer selection table may be updated by receiving network state information and information on other adjacent mobile peers from each of the plurality of mobile peers. In addition, the overlay structure may be configured based on block transmission delay time information of each of the plurality of mobile peers so that the overall block propagation time is shortened the most, and the block transmission delay time information may be included in the network state information. For example, the plurality of mobile peers may include at least some first mobile peers included in the cellular network peer group and the remaining second mobile peers included in the device to device (D2D) network peer group. A first mobile peer may receive the block information from the MEC server through a cellular network, and a second mobile peer receives the block information from a neighboring mobile peer of the at least some first mobile peers through a D2D network can do. That is, the first mobile peer may receive block information directly from the MEC server, and the second mobile peer may receive block information from the first mobile peer that has received the block information from the MEC server. This has been described in detail with reference to FIGS. 4 to 8 .

For example, the block delay time information may be derived based on a size of block information and a data rate from the MEC server to the first mobile peer in the case of the first mobile peer, and case, it may be derived based on the size of the block information and the data rate from the adjacent mobile peer to the second mobile peer. This has been described in detail with reference to FIG. 9 .

It is possible to receive notification information on which verification and commit of the block information has been performed from the plurality of mobile peers (S1170), and transmit response information indicating that the transaction proposal has been processed to the user terminal based on the notification information. can be (S1180).

The operation according to the embodiment of the present invention can be implemented as a computer-readable program or code on a computer-readable recording medium. The computer-readable recording medium includes all types of recording devices in which data readable by a computer system is stored. In addition, the computer-readable recording medium is distributed in a computer system connected to a network so that computer-readable programs or codes can be stored and executed in a distributed manner.

In addition, the computer-readable recording medium may include a hardware device specially configured to store and execute program instructions, such as ROM, RAM, and flash memory. The program instructions may include not only machine language codes such as those generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like.

Although some aspects of the invention have been described in the context of an apparatus, it may also represent a description according to a corresponding method, wherein a block or apparatus corresponds to a method step or feature of a method step. Similarly, aspects described in the context of a method may also represent a corresponding block or item or a corresponding device feature. Some or all of the method steps may be performed by (or using) a hardware device such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, one or more of the most important method steps may be performed by such an apparatus.

In embodiments, a programmable logic device (eg, a field programmable gate array) may be used to perform some or all of the functions of the methods described herein. In embodiments, the field programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described herein. In general, the methods are preferably performed by some hardware device.

Although the above has been described with reference to the preferred embodiments of the present invention, those skilled in the art can variously modify and change the present invention within the scope without departing from the spirit and scope of the present invention as set forth in the claims below. You will understand that it can be done.

Claims (10)

As a block data multicasting method based on a scalable peer to peer (P2P) overlay structure performed in a mobile edge clouding (MEC) server,
receiving a request for a transaction proposal from a user terminal;
sending the transaction proposal to at least one endorsing mobile peer;
receiving guarantee information including smart contract execution information and signature information according to the transaction proposal from the at least one indoling mobile peer;
generating a transaction based on the guarantee information;
generating block information based on the transaction;
propagating the block information to a plurality of mobile peers including the indoling mobile peer according to a preconfigured overlay structure;
receiving, from the plurality of mobile peers, notification information on which verification and commit of the block information has been performed; and
transmitting response information indicating that the transaction proposal has been processed to the user terminal based on the notification information; containing,
Block data multicasting method. The method according to claim 1,
The overlay structure is configured based on a peer selection table,
The peer selection table is updated by receiving network state information and information on other adjacent mobile peers from each of the plurality of mobile peers.
Block data multicasting method. 3. The method according to claim 2,
The overlay structure is configured based on block transmission delay time information of each of the plurality of mobile peers, and the block transmission delay time information is included in the network state information,
Block data multicasting method. 4. The method according to claim 3,
The plurality of mobile peers include at least some first mobile peers included in the cellular network peer group and the remaining second mobile peers included in the device to device (D2D) network peer group,
The first mobile peer receives the block information from the MEC server through a cellular network,
wherein the second mobile peer receives the block information from a neighboring mobile peer among the at least some first mobile peers through a D2D network;
Block data multicasting method. 5. The method according to claim 4,
The block transmission delay time information is
In the case of the first mobile peer, it is derived based on the size of block information and the data rate from the MEC server to the first mobile peer,
In the case of the second mobile peer, it is derived based on the size of block information and the data rate from the neighboring mobile peer to the second mobile peer,
Block data multicasting method. As a mobile edge clouding (MEC) server that performs a block data multicasting method based on a scalable peer to peer (P2P) overlay structure,
processor; and
a memory storing at least one instruction executed by the processor; including,
The at least one command is
is executed to receive a request for a transaction proposal from the user terminal;
and send the transaction proposal to at least one endorsing mobile peer;
and receive endorsement information including smart contract execution information and signature information according to the transaction proposal from the at least one indoling mobile peer;
executed to create a transaction based on the guarantee information;
is executed to generate block information based on the transaction,
propagating the block information to a plurality of mobile peers including the indoling mobile peer according to a preconfigured overlay structure;
is executed to receive notification information on which verification and commit of the block information has been performed from the plurality of mobile peers;
is executed to transmit response information indicating that the transaction proposal has been processed to the user terminal based on the notification information,
MEC Server. 7. The method of claim 6,
The overlay structure is configured based on a peer selection table,
The peer selection table is updated by receiving network state information and information on other adjacent mobile peers from each of the plurality of mobile peers.
MEC Server. 8. The method of claim 7,
The overlay structure is configured based on block transmission delay time information of each of the plurality of mobile peers, and the block transmission delay time information is included in the network state information,
MEC Server. 9. The method of claim 8,
The plurality of mobile peers include at least some first mobile peers included in the cellular network peer group and the remaining second mobile peers included in the device to device (D2D) network peer group,
The first mobile peer receives the block information from the MEC server through a cellular network,
wherein the second mobile peer receives the block information from a neighboring mobile peer among the at least some first mobile peers through a D2D network;
MEC Server. 10. The method of claim 9,
The block transmission delay time information is
In the case of the first mobile peer, it is derived based on the size of block information and the data rate from the MEC server to the first mobile peer,
In the case of the second mobile peer, it is derived based on the size of block information and the data rate from the neighboring mobile peer to the second mobile peer,
MEC Server.

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