WO2018032371A1

WO2018032371A1 - Power consumption perception pow consensus mechanism for block chain

Info

Publication number: WO2018032371A1
Application number: PCT/CN2016/095575
Authority: WO
Inventors: 张丛
Original assignee: 深圳市樊溪电子有限公司
Priority date: 2016-08-13
Filing date: 2016-08-16
Publication date: 2018-02-22
Also published as: CN106296191A

Abstract

A power consumption perception PoW consensus mechanism for a block chain, comprising the following process steps: (1) in a Bitcoin system, all nodes compete with each other on the basis of respective computer computing power to jointly solve an SHA math problem that is complex to solve but easy to verify, and a node which solves the problem at the fastest speed obtains a block accounting right and Bitcoin award automatically generated by the system; (2) interconnecting physical servers located at different geographical locations by using a WDM mesh network to form a block chain infrastructure network, generating power consumption in response to a block chain request, integrating block chain nodes on light load servers to fewer physical servers, directing communication requirements to fewer links, and turning off unnecessary servers and nodes. By using the power consumption perception PoW consensus mechanism, resource potential of the infrastructure network can be further exploited while the performance of the block chain is improved; in addition, power consumption can be perceived, so as to reduce carbon emission and greenhouse effect.

Description

A PoW Consensus Mechanism for Blockchain Power Awareness

Technical field

The invention relates to a blockchain PoW consensus mechanism, in particular to a power consumption-aware blockchain PoW consensus mechanism.

Background technique

The emergence of Bitcoin in 2009 brought a subversive result - blockchain technology, blockchain is a secure account book database, composed of data blocks, users can constantly update and upgrade here. The platform looks for data. For financial institutions, the blockchain can speed up transaction processing, reduce costs, reduce middlemen, improve market insight, and increase business transparency.

How to achieve consensus in distributed systems is an important research issue in the field of distributed computing. One of the advantages of blockchain is that it can make each node efficiently target block data in a decentralized system with highly decentralized decision-making power. A consensus is reached on effectiveness. The early bitcoin blockchain uses a workload that is highly dependent on the node's computational power, that is, Proof of work, which is the PoW mechanism to ensure the consistency of distributed accounting in the bitcoin network. The core idea is to introduce the calculation of distributed nodes. Competing to ensure data consistency and consensus security, its near-perfect integration of the currency issue, transaction payment and verification functions of the Bitcoin system, through the power of competition to ensure the security and decentralization of the system, PoW consensus mechanism There are very significant flaws, and its powerful computing power wastes resources, such as electricity, and the 10-minute transaction confirmation time makes it relatively unsuitable for commercial applications of small transactions.

At present, the PoS consensus mechanism is proposed to solve the problem of resource waste and security defects. In essence, it uses the equity proof to replace the hash-based workload proof in PoW, which is the highest right in the system. The node that benefits rather than the highest computing power obtains the block accounting right. However, the consensus process relies only on the internal currency age and equity, and does not need to consume external computing power and resources, which solves the problem of wasting power, but the computing power is greatly reduced. .

We know that blockchain is a completely different way of computing from cloud computing. In a sense, the two are opposite. However, cloud computing based on network virtualization technology can be carried out under the premise of satisfying service level agreement SLAs. Power consumption awareness, while further improving the network performance while further exploring the resource potential of the infrastructure network, while also sensing power consumption, reducing carbon emissions and the greenhouse effect.

Summary of the invention

The object of the present invention is to provide a PoW consensus mechanism for blockchain power consumption, and the consensus mechanism includes the following process steps: (1) In the bitcoin system, each node competes with each other based on their respective computing powers to solve a solution. A complicated but easy-to-verify SHA math problem, the node that solves the problem is the fastest to obtain the block billing right and the bitcoin reward automatically generated by the system; (2) the WDM mesh network is used to interconnect the physical servers located in different geographical locations. Blockchain infrastructure network, responding to blockchain requests to generate power consumption, consolidating blockchain nodes on light-loaded servers onto fewer physical servers, routing communication requirements to fewer links, closing "no Necessary" servers and nodes.

Preferably, the SHA math problem can be expressed as solving a suitable random number by searching according to the current difficulty value, so that the double SHA hash value of each element value of the block head is less than or equal to the target hash value.

Preferably, the bitcoin system adjusts the difficulty value of the random number search to control the average generation time of the block to be 6 minutes.

Preferably, the PoW consensus random number search process comprises the following steps: (1) collecting the entire network unconfirmed transaction of the current time period, and adding a Coinbase transaction for issuing a new bitcoin reward to form a current block body. (2) Calculate the Merkle root of the block transaction set into the block header, and fill in the other metadata of the block header, where the random number Nonce is set to zero; (3) Random number Nonce plus 1, calculate the current block header Double SHA hash value, if it is less than or equal to the target hash value, it succeeds Search for the appropriate random number and obtain the accounting rights of the block; otherwise continue to step (3) until any node searches for the appropriate random number; (4) if the time is not successful, update the timestamp and Continue to search after unacknowledging the transaction set, recalculating the Merkle root.

Preferably, the power consumption includes power consumption related to a traffic load and power consumption independent of a traffic load.

Preferably, the power aware blockchain is modeled using a mixed integer programming (MIP) algorithm.

The power-aware PoW consensus mechanism is used to further exploit the resource potential of the infrastructure network while improving the performance of the blockchain, while also sensing power consumption and reducing carbon emissions and the greenhouse effect.

The above as well as other objects, advantages and features of the present invention will become apparent to those skilled in the <

DRAWINGS

Some specific embodiments of the present invention are described in detail below by way of example, and not limitation. The same reference numbers in the drawings identify the same or similar parts. Those skilled in the art should understand that the drawings are not necessarily drawn to scale. The objects and features of the present invention will become more apparent in consideration of the following description in conjunction with the accompanying drawings.

FIG. 1 is a schematic diagram of a PoW consensus mechanism for blockchain power consumption sensing according to an embodiment of the invention.

2 is a flowchart of a random number search of a PoW consensus mechanism according to an embodiment of the present invention.

detailed description

Before proceeding with the description of the specific embodiments, in order to more clearly express the content discussed, first define some very important concepts.

Trading: The essence of a transaction is a relational data structure that contains information about the value transfer of the trading participants. These transaction information is called the accounting ledger. The transaction needs to go through three creation, verification, and writing blockchains. The transaction must be digitally signed to ensure the legality of the transaction.

Block: All transaction information is stored in the block, and a transaction information is a record, which is stored as a separate record in the blockchain. The block is composed of the block header and the data part, and the block header The segment contains various characteristics of the block itself, such as the previous block information, merkle value and time stamp. The block header hash value and block height are the two most important indicators for identifying the block. The block primary identifier is its cryptographic hash value, a digital fingerprint obtained by performing a second hash calculation on the block header by the SHA algorithm. The resulting 32-byte hash value is called the block hash value, or the block header hash value, and only the block header is used for calculation. The block hash value can uniquely and unambiguously identify a block, and any node can independently obtain the block hash value by simply hashing the block header.

Blockchain: A data structure in which blocks are chained in an orderly fashion. A blockchain is like a vertical stack, with the first block being the first block at the bottom of the stack, and each block is then placed on top of the other blocks. When a block is written to a blockchain, it will never change and is backed up to another blockchain server.

Embodiment: Referring to FIG. 1 , a blockchain power-aware PoW consensus mechanism includes the following process steps: (1) In a bitcoin system, each node competes with each other based on their respective computing powers to solve one problem. Solve the complex but proven SHA math problem, the node that solves the problem is the fastest to obtain the block billing right and the bitcoin reward automatically generated by the system; (2) The WDM mesh network is used to interconnect the physical servers located in different geographical locations. Forming a blockchain infrastructure network, responding to blockchain requests to generate power consumption, consolidating blockchain nodes on light-loaded servers onto fewer physical servers, diverting communication requirements to fewer links, and shutting down Unnecessary "servers and nodes.

The SHA math problem can be expressed as solving a suitable random number by searching according to the current difficulty value so that the double SHA hash value of each element value of the block head is less than or equal to the target hash value. The bitcoin system adjusts the difficulty value of the random number search to control the average generation time of the block to be less than 10 minutes, preferably within 6 minutes, to meet the needs of fast processing transactions.

Referring to FIG. 2, the PoW consensus random number search process includes the following steps: (1) collecting the entire network unconfirmed transaction of the current time period, and adding a Coinbase transaction for issuing a new bitcoin reward to form a current block transaction. (2) Calculate the Merkle root of the block transaction set into the block header, and fill in the other metadata of the block header, where the random number Nonce is set to zero; (3) the random number Nonce plus 1, calculate the current block header Double SHA hash value, if it is less than or equal to the target hash value, it succeeds Search for the appropriate random number and obtain the accounting rights of the block; otherwise continue to step (3) until any node searches for the appropriate random number; (4) if the time is not successful, update the timestamp and Continue to search after unacknowledging the transaction set, recalculating the Merkle root. Power consumption includes power consumption related to traffic load and power consumption independent of traffic load. Power consumption independent of traffic load is called useless power. In the power-aware PoW consensus mechanism, unnecessary basic work can be reduced. It is used to achieve energy saving, and the working state is divided into an active mode and an off mode. In this embodiment, two nodes a and d of the blockchain are mapped to the physical server S1, and the remaining two nodes b and e are integrated to the physical server S2, and the other two base points c and f are integrated into the physical On server S3, links (ab) and (de) are mapped onto physical path (AB), links (bc) and (ef) are mapped onto physical path (BC), link (ca) and ( Fd) is mapped to the physical path (CA). In the power-aware blockchain mapping, unnecessary servers and nodes are shut down by traffic load integration and grooming, reducing power consumption by about 50%. In the mapping server algorithm, the mixed-integer programming (MIP) algorithm is used to model the power-aware blockchain, and the power-aware block-connection problem is modeled as a mathematical optimization problem to minimize the total power consumption. The optimization objective function is defined as follows:

Minimize{η·Pnetwork+ξ·Pserver} (1)

The objective function attempts to minimize the total power consumption of the blockchain under the PoW consensus mechanism, including network power consumption and server power consumption, where η+ξ=1, which are used to balance the weight of network power and server power consumption, respectively. At the same time, some specific constraints need to be met, including resource capacity constraints, location constraints, etc., and the constraints are:

(1) node "flow conservation";

(2) The amount of resources provided by the node to the block connection does not exceed the amount of resources available to itself;

(3) The total amount of service bandwidth carried by each link in the low-rate service state of the user cannot exceed the tolerance limit.

(4) The underlying physical network has the lowest total long-term power consumption.

After the solution of the objective function is completed, the remaining two important tasks, block chain node mapping and link mapping, need to be completed to jointly consider the resource requirements of the node and the bandwidth resource requirements of the adjacent links, according to the resource requirements. After the order is arranged, the node chain resource utilization efficiency and acceptance rate are calculated, and the different power consumption implementation paths are selected by using the minimum power path limited principle. The resource demand is defined as:

Where req(v) represents the server resource requirement of node v, b(e) represents the link bandwidth resource requirement of link e, and Adj(v) represents the neighboring link set of node v.

The node and link allocation mechanism can be obtained by calculating the above resource demand by using the normalized penalty factor algorithm.

The present invention has been described with reference to the specific illustrative embodiments, and is not limited by the scope of the appended claims. It will be appreciated by those skilled in the art that the embodiments of the invention can be modified and modified without departing from the scope and spirit of the invention.

Claims

A PoW consensus mechanism for blockchain power consumption is characterized in that the consensus mechanism includes the following process steps:

S1 In the Bitcoin system, each node competes with each other based on their respective computer powers to solve a complex mathematical problem that is easy to verify, and the node that solves the problem is the fastest to obtain block accounting rights and the system automatically generates bitcoin. reward;

S2 uses WDM mesh network to interconnect physical servers located in different geographical locations to form a blockchain infrastructure network. The response block generates power consumption in response to the request, and integrates the blockchain nodes on the light load server into fewer physical servers. On the other hand, the communication requirements are diverted to fewer links, and the "unnecessary" servers and nodes are turned off.
The blockchain power consumption-aware PoW consensus mechanism according to claim 1, wherein the SHA mathematical problem can be expressed as: calculating a suitable random number by searching for a block head element according to a current difficulty value. The double SHA hash value of the value is less than or equal to the target hash value.
The blockchain power consumption-aware PoW consensus mechanism according to claim 2, wherein the bitcoin system adjusts the difficulty value of the random number search to control the average generation time of the block to be 6 minutes.
The blockchain power consumption-aware PoW consensus mechanism according to claim 2, wherein the PoW consensus random number search process comprises the following steps:

D1 collects the entire network unconfirmed transaction of the current time period, and adds a Coinbase transaction for issuing new bitcoin rewards to form a transaction set of the current block;

D2 calculates the Merkle root of the block transaction set into the block header, and fills in other metadata of the block header, where the random number Nonce is set to zero;

D3 random number Nonce plus 1, calculate the double SHA hash value of the current block header, if less than or equal to The target hash value, successfully search for a suitable random number, and obtain the billing right of the block; otherwise continue to step D3 until any node searches for a suitable random number;

If D4 is unsuccessful within a certain period of time, the timestamp and unconfirmed transaction set are updated, the Merkle root is recalculated, and the search is continued.
A blockchain power-aware PoW consensus mechanism according to claim 1, wherein the power consumption comprises power consumption related to a traffic load and power consumption independent of a traffic load.
A blockchain power-aware PoW consensus mechanism according to claim 1, wherein the power-aware blockchain is modeled using a mixed integer programming (MIP) algorithm.
The blockchain power consumption-aware PoW consensus mechanism according to claim 6, characterized in that the power-aware block connection problem is modeled as a mathematical optimization problem solution to minimize the total power consumption as follows Optimization objective function (1):

Minimize{η·Pnetwork+ξ·Pserver} (1)

The objective function attempts to minimize the total power consumption of the blockchain under the PoW consensus mechanism, including network power consumption and server power consumption, where η+ξ=1, which are used to balance the weight of network power and server power consumption, respectively.
The blockchain power consumption-aware PoW consensus mechanism according to claim 7, characterized in that: the optimization objective function (1) is satisfied to satisfy a resource capacity constraint, and the location constraint condition is: a node "flow conservation"; The amount of resources provided to the block connection does not exceed the amount of available resources; the total amount of service bandwidth carried by each link in the low-rate service state of the user cannot exceed the tolerance limit; and the long-term total power consumption of the underlying physical network is the lowest.
A blockchain power consumption-aware PoW consensus mechanism according to any of claims 6-8, characterized in that: blockchain node mapping and link mapping are synergistically considering node resource requirements and bandwidth resource requirements of adjacent links. After the nodes are sorted according to the resource demand, the blockchain resource utilization efficiency and the acceptance rate are calculated, and the minimum power consumption path limited principle is used to select different power consumption implementation paths, wherein the resource demand is as follows ( 2):

Where req(v) represents the server resource requirement of node v, b(e) represents the link bandwidth resource requirement of link e, and Adj(v) represents the neighboring link set of node v.
A blockchain power consumption-aware PoW consensus mechanism according to claim 9, wherein the resource demand is calculated by using a normalized penalty factor algorithm to obtain a node and link allocation mechanism.