With the continuous hype of Online casino and How to find it, the price is getting higher and higher, and Online casino and How to find it has become the main means of interest transmission in an increasing number of economic crime cases. The relevant departments have increased the打击力度 against Online casino and How to find it, but the number of related cases is still high. At the same time, in the current work of electronic data evidence collection, the existing investigation methods involving Online casino and How to find it also face many problems, such as large workload, high analysis difficulty, and difficulties in evidence collection and freezing.

　　This article, as the second part of

　　In response to the difficulties encountered in the electronic evidence collection process of the case of Online casino and How to find it proposed in the first part of the article

　　The overall approach mainly includes the following aspects: first, we need to find the analysis object, that is, the data source: the target wallet address, which involves the retrieval of wallet addresses and the forensic technology of Online Casino and How to Find It transaction-related APPs and PC programs; second, after obtaining the target wallet address, we need to download and clean the same-chain data to achieve the analysis of transaction records and fund flow of the target wallet address, involving the analysis technology of wallet address transaction records; third, wallet addresses are anonymous, only the wallet addresses belonging to centralized exchanges can be attested, so it involves the attribution tag technology of wallet addresses; finally, the storage and compliant disposal of seized Online Casino and How to Find It, involving the storage and compliant disposal technology of Online Casino and How to Find It.

　　Secondly, innovative technologies and analytical thinking

　　1. Forensic Technology of Online Casino and How to Find It Wallet Address

　　The sources of wallet addresses mainly include three aspects. Firstly, the wallet address mainly comes from the Online Casino and How to Find It transaction-related APPs and PC programs, where the local data and cloud data of related mobile wallet APPs, exchange APPs, PC programs can be collected for evidence, such as imtoken, BitPay, and other wallet APPs, Huobi, Binance, OKEX, and other exchange APPs, which can extract related deposit and withdrawal transaction records, login IP, and other information. It is worth pointing out that although the transaction records of wallet addresses can be queried on the chain, for centralized exchanges, some transaction records of Online Casino and How to Find It are only recorded internally in the exchange and not synchronized to the public chain, such as internal buy and sell matching orders in the exchange, which cannot be queried on the public chain. Therefore, it is necessary to collect evidence from the Online Casino and How to Find It transaction-related APPs and PC programs to ensure the integrity of the evidence data.

　　Secondly, the wallet address may come from the conversation records of chat software, usually appearing in the form of strings, word combinations (private key of the wallet address), etc., and can be retrieved by regular expressions for related wallet addresses.

　　Finally, the wallet address may also be stored in albums and other media files or on PC computers in the form of images. The wallet address or key related images can be identified by OCR technology, so the forensic evidence of the wallet address of Online Casino and How to Find It mainly targets the related evidence materials, including transaction APPs, chat records, albums, and so on.

　　2. Analysis Technology of Online Casino and How to Find It Transaction Records

　　对Online casino and How to find it 钱包地址的交易记录、资金流向的分析在电子数据取证分析工作中尤为重要。Online casino and How to find it 交易记录的分析一般分为几个步骤：以比特币为例，首先下载比特币节点数据，包括全节点、轻节点、挖矿节点等，可根据分析需要下载所需数据，当然全节点数据最全lottery and Just click to enter。下载比特币区块的数据一般可通过多种方法实现，如通过Bitcoin Core 软件同步比特区块链数据、或通过实现比特币P2P 网络协议建立比特币全节点同步区块数据、或通过区块链浏览器提供的API 接口来同步数据。

　　下载到区块链数据后，下一步需要建立区块链数据分析模型，比特区块链数据分析模型采用了UTXO 分析模型，UTXO 即Unspent TX Output未花费的交易输出，是比特币交易的基本单位。任何一个交易总是由若干个输入和输出构成，除Coinbase 交易，即创币交易，Coinbase 交易是系统给矿工的挖矿奖励，只有输出没有输入。所以每个交易的输入和输出都可以串联起来，从而可以构建输入与输出的数据模型。最后将区块数据写入到数据库中实现区块数据的解析、清洗工作，从而实现了可视化区块数据的交易记录、资金流向分析等工作。UTXO 模型与传统交易模型有些不同，传统交易模型主要是基于账户设计，以账户余额为核心，由交易数据库提供支撑。UTXO 模式是由若干个输入和输出构成的链式结构，所有交易都可追溯到前一个或者多个交易的输出。

　　下面举个例子进行说明，如下图所示，A 某通过挖矿获得了25 个比特币并存在了自己的钱包地址下，Block1 交易只有输出没有输入，该交易称为coinbase 交易。过几天A某分别转给了B 某5 个比特币、C 某10 个比特币，在Block2 交易中产生了3 个UTXO，分别为A 某钱包地址下的10 个比特币，B 某的5 个比特币，C某的10 个比特币。又过几天B 某、C 某又分别给D 某转了2.5 个比特币，在Block3 交易中产生了4个UTXO，即A、B、C、D 未花费的交易分别为10、2.5、7.5、5 个比特币。因此与传统账户交易相比，UTXO 交易只需查看最后一次交易即可查看到对应钱包地址下的余额，因此UTXO 模型的建立在区块链数据分析模型中尤为重要。

　　In the actual evidence analysis process, due to the real-time increase of blockchain transaction data and the large volume of transactions, the current size of the Bit Block data has reached nearly 400GB, and it is growing at a speed of more than 50GB per year, posing higher technical challenges to the servers running full nodes and their performance. At the same time, there are many types of Online casino and How to find it, and the amount of adaptation work is large. Currently, the analysis work mainly supports mainstream currencies, and small currencies can be added for adaptation support according to the needs of the case.

　　3. Tagging technology for Online casino and How to find it wallet addresses

　　The wallet address tagging technology refers to automatically marking the types of exchanges, wallet APPs, mining pools, etc. to which the wallet address belongs, which facilitates the subsequent retrieval of registration and transaction information under the corresponding wallet address from the exchange. The wallet address tagging system mainly obtains wallet address big data, extracts the main features, and marks the wallet addresses through clustering based on the similarity between features. The commonly used algorithms are usually based on unsupervised social network node sorting and community discovery algorithms, as well as semi-supervised or supervised graph embedding or social network representation learning algorithms to construct the blockchain wallet address tagging system, realizing the automatic marking of wallet address attributes, thus the accuracy and integrity of the tagging system are particularly important for subsequent evidence verification work.

　　4. Professional deposit technology for Online casino and How to find it

　　At present, in actual cases, we are faced with the issue of how to legally deposit the seized Online casino and How to find it, as the current deposit methods mainly involve transferring the seized Online casino and How to find it to a personal application wallet address, purchasing a hardware wallet, or storing it in an exchange. However, the current storage methods also face many problems, such as the loss of private keys of wallet addresses, the closure of exchanges, and the unauthorized transfer of Online casino and How to find it, which may all lead to the loss of Online casino and How to find it. For seized Online casino and How to find it involving large amounts of money, it also involves the joint approval of multiple law enforcement departments. Therefore, designing a professional customized deposit tool for Online casino and How to find it becomes particularly necessary.

　　The design of the custody tool should focus on solving two problems: the security of the wallet address key and the joint approval of multiple law enforcement departments. The commonly used technical means at present is mainly to adopt MPC (Secure Multi-Party Computation) secure multi-party algorithm, which can solve the problem of joint collaboration among multiple untrusted participantsOnline casino and Just click to enter. Through MPC technology, it is possible to achieve privacy data sharing under the premise of protecting personal privacy data, to achieve key sharing, the principle is shown in the figure below. This technology can split the key, and each piece after splitting can be kept by different participants. Individuals cannot recover the key, and only through joint collaboration and communication among multiple people can the key file be recovered. Therefore, by using this technology, it can simultaneously solve the security problem of the key and the joint approval problem of multiple departments.

　　5. Compliance Disposal Technology for Online casino and How to find it

　　Since September 24, 2021, the state has explicitly defined that all transaction activities related to Online casino and How to find it are illegal. However, the seized Online casino and How to find it cannot be directly deposited into the public accounts of law enforcement departments and must be converted into legal currency. How to legally convert Online casino and How to find it into legal currency is currently the main problem faced. The existing handling method is still to use private transactions, that is, transactions between individuals, but this method has legal risks and is also non-compliant. We know that Online casino and How to find it is obtained through computing power, so the possibility of equating computing power with Online casino and How to find it has become a possibility. Of course, this disposal method also needs to be verified by practice. Whether the disposal subject is handled by state institutions or entrusted to third-party institutions is also a direction to be explored in the future.