INFORMATION AND WEB TECHNOLOGIES

. Leveraging technological advances to provide a permanent audit log for a tracked asset is the main goal of blockchain-based supply chain management systems. The challenge, however, is to monitor the asset as it moves through various blockchain-based distribution networks. The paper suggests a model that was developed specifically to solve these problems. The proposed model allows you to do the following: track an asset in various blockchain - based supply chain systems; cryptographically verify the asset's supply chain; define asset data in a standard format; and describe it using several standard formats. Thus, the model offers a significant advantage in terms of interaction between different blockchain-driven supply chains compared to other models presented in the literature

Introduction.The objective of the work is to suggest a new model that provides answers to issues pertaining to the interoperability and standardisation of supply chain systems that are based on blockchain technology.There has been a recent uptick in the number of applications that make use of blockchain technology in the supply chains of pharmaceutical goods and medical equipment.Because of the paradigm that has been proposed, every asset that is being monitored inside a blockchain-based supply chain system is displayed as verified credentials.The model has been modified so that it may be used in supply chain systems, and it conforms to the World Wide Web Consortium's recommendation for the provision of verified online credentials.Other topics are not within the purview of this study; the only exception to this is the consideration given to the system performance difficulties connected to the storage capacity issue during the model creation process.The purpose of our research is to identify a solution to improve the interoperability of blockchainbased supply chain platforms that have been described in the existing body of academic work.A new model has been developed as a result of this research, and its contribution can be summed up as follows: It allows for compatibility between various blockchain-based supply chain systems; it enables the definition of data related to each asset that is tracked in the blockchain-based supply chain in a variety of standardised formats; and it stores all data related to asset tracking in the blockchain-based supply chain in an autonomous manner.
Literature review.A distributed ledger system, often known as blockchain [1] maintains an immutable digital record of transactions.This record may be read by the platform's users, and it can also be confirmed by third parties.Because of its one-of-a-kind properties, blockchain has the potential to be utilized unique in a broad variety of additional settings [2,3].Blockchain is well recognised for serving as the digital underpinning of cryptocurrencies such as Bitcoin and Ethereum.The applications of blockchain technology extend far beyond the realm of the digital, having an impact not just on business but also on society, goods, and the processes that businesses use [4].Numerous blockchain consortia have begun to form in order to develop business applications and enterprise applications for businesses in a No 155 variety of industries, including healthcare and pharmaceuticals [5,6], automotive [7,8], and international transportation and logistics [9].In 2016, there were 31 such blockchain consortia, but it is anticipated that this number will expand to 478 by the year 2023.Even though many of these enterprise applications are still in the early stages of development or have only recently appeared on the market, the growing number of established collaborations and consortia is an indication of the growing interest and prospects of blockchain for various enterprise applications.Additionally, it provides a glimpse into the more far-reaching implications of the technology, particularly with regard to commercial networks and digital business ecosystems.The potential of blockchain technology has recently come to the attention of researchers [10].Blockchain technology is intriguing for a wide variety of applications because of the technological advantages it offers.According to the findings of the literature analysis [11], potential expansion areas include financial applications, integrity checks, governance, the Internet of Things, healthcare, education, privacy and security, data management, and business and industry.Other areas where blockchain technology is generating a lot of interest include supply chains (SC) and logistics management.Within [12][13][14], we examined the technical capabilities of blockchain for the purpose of identifying potential applications within the supply chain.In [15], authors investigate how SC information systems might benefit from blockchain technology by evaluating its multiple elements.Specifically, we focus on how SC information systems can benefit from distributed ledgers.Several studies have been done on the potential use of blockchain in the supply chain, such as tracking product history [16][17][18][19], facilitating transactions in the supply chain, and so on [20].
Proposed Model.In the real world, credentials are used all the time.A driver's license is one of these certificates, since it proves that the bearer is competent to drive a vehicle.Another, more specific example is a state-issued passport, which is used to confirm identity when traveling abroad.When we use these credentials in the real world, we usually get some benefits.However, it is still difficult to No 155 get the same benefits from using digital credentials as using physical ones in the physical world, and using such thirdparty verified credentials digitally online is still difficult.The regulatory specification for transmitting credentials on the Internet in a way that is machineverifiable, respects privacy, and is cryptographically secure was released as part of the standard for transmitting verifiable information on the Internet.This specification defines verified credentials as those that can be cryptographically verified as issued by the intended author.The owner, issuer, entity, verifier, and verified data registry are the main entities in the credential verification ecosystem, along with the relationships between them.There are four entities (owner, issuer, entity, and verifier) that exist separately from the ecosystem and play an important role in it.The statements that the issuer makes about the topic are used to create verified credentials, which are subsequently issued to the owner and delivered to him.There are claims about this thing, and in many cases, it is directly related to someone whose credentials can be verified.The bearer places the issued credentials in a secure location (for example, in a vault or personal wallet with verified credentials).
Owners are subject to verification of credentials and also have the right, at their discretion, to decide whether to share them with third parties (verifiers) or not.In most cases, the verifier will ask the owner to provide credentials provided by the issuer that can be verified.The verifier will be able to perform cryptographic verification of the credentials provided by the owner later.Verifying user credentials requires a verifiable credential ecosystem, and a verifiable data registry plays a crucial role in this ecosystem, providing data generation and validation.Reliable databases, decentralized databases, government identification databases, and distributed ledgers (such as blockchain) can all be used to create registers that can be trusted to be accurate.Multiple registries of different types are often used in conjunction with each other when verifying credentials.
Verifiable credentials rely heavily on public key cryptography, particularly the digital signature method, to No 155 perform their core functions, making them more secure and secure from unauthorized access than physical credentials.
Figure 1 shows a model for verifying credentials that can be cryptographically verified at any time as a group of statements made by the same issuer and expressing specific statements about the subject.A separate verified credentials approval component stores these statements.

Supply Chain Credential Verification Model
Metadata and evidence components are also important parts of verified credentials, as well as a component of claims.Credential metadata includes information such as credential ID, older ID, issuer ID, expiration date, verification services, and other information.The credential schema is the most important data stored in this component.Context is another name for this schema, which is often, but not always, specified as a JSON-LD file.The attributes (e.g.owner, issuer, etc.) and formats used in the credentials and proof approval components are defined by the schema.The ability to extend the data model is another important component of verified credentials.Additional machine-readable schemas that are specified in the verified credentials metadata component can be added to an existing schema to extend its data.Thus, verified credentials can contain multiple schemas that have been extended from the original W3C verified credentials data model and contain newly defined attributes.The original data model, i.e. verified W3C credentials, must always be defined in the verified credentials metadata component to ensure that credentials with multiple defined schemas in the metadata component meet the standard for expressing verified credentials online.The above-mentioned mechanisms and procedures ensure semantic compatibility of credentials in the event of an extension of the proposed credential model.When the collection of unauthorized statements from the approval component and the credentials metadata from the metadata component are combined into a single document and subsequently digitally signed by the Issuer, the credentials are actually verified.The results of this transaction, or digital signatures, are collected in the verified credentials verification component, which allows anyone to whom credentials are transmitted to cryptographically demonstrate who is the issuer of the verified credentials.Verifiable credentials can be created using various cryptographic digital signature mechanisms.In addition, the use of digital signatures guarantees verification of credentials, ensuring that they have not been changed at the time of transmission and are presented together with data, such as statements, in the same form in which Vo is verifiable, the issuer is not allowed to challenge the authorship of any statements made in connection with these credentials.The verifier trusts the issuer to issue credentials with relevant data, so proof is necessary to establish trust between the issuer and the verifier within the verifiable credentials ecosystem.The data registry checker must be trusted by all parties; since it cannot be changed, the information contained in it is accurate.The Examiner and owner must believe in the issuer and that the statements they make are true.The owner must be confident in the security of the storage that contains their verifiable credentials.Since the model ensures that neither the verifier nor the issuer must trust the owner's credential store, i.e. a third party, this trust model is different from other models.They can only communicate directly with each other and trust identity cards that have passed successful cryptographic verification.In addition, the issuer is free  Other types of information also make up this component.The verifiable credential schema is the most important part of the data that should be stored in this component.This schema, also known as a context, is often provided as a JSON-LD file, although this is not always the case.The data model is also known as attributes (such as "owner", "issuer", etc.), and their forms are defined by the schema.The data represented by the schema can be extended by adding other machine-readable schemas if these schemas are described in the verified credential metadata component.As a direct result of this, single credentials can consist of many schemas, each of which can include newly defined functions and has been extended from the basic W3C credential model.To ensure that verified credentials that have multiple defined schemes in the metadata component meet the standard for expressing verified credentials online, the source data model, also known as verified W3C credentials, must always be defined in the verified credentials metadata component.This is the only way to ensure that verifiable credentials can be used with multiple specific schemas in the metadata component.

Conclusion.
Blockchain technology has gained significant attention in recent years due to its potential to revolutionize the way we store and exchange data.Supply chain management is one of the areas that could greatly benefit from the use of blockchain technology, as it provides a secure and transparent way to track and manage the movement of goods and information across the supply chain.
A new model of information system for supply chain based on blockchain would involve using a decentralized ledger to store and track information about every stage of the supply chain, from raw materials to finished products.This information could include details about the origin and quality of the materials used, the manufacturing process, and the distribution and delivery of the products.
By using blockchain technology, this information would be secured using cryptography and distributed across a network of nodes, making it difficult for any one party to manipulate the data.This would increase transparency and accountability in the supply chain, reducing the risk of fraud, errors, and delays.
Moreover, blockchain technology also enables the use of smart contracts, which are self-executing contracts with the terms of the agreement between buyer and seller being directly written into lines of code.This would enable automated This work is distributed under the terms of the Creative Commons Attribution-ShareAlike 4.0 International License (https://creativecommons.org/licenses/by-sa/4.0/).Proceedings of the 1st International Scientific and Practical Conference «Modern Knowledge: Research and Discoveries» (May 19-20, 2023).Vancouver, CanadaNo 155to make claims against the owner without having to know or believe the inspector.The digital signature model of the proposed model for tracking assets (for example, pharmaceutical products) using blockchain-based supply chains is shown in Figure2.

Figure 2 digital
Figure 2 digital signature generation model