The role of intermediaries in electronic marketplaces: developing a contingency model

Abstract. Early research in electronic markets seemed to suggest that e‐ commerce transactions would result in decreased costs for buyers and sellers alike, and would therefore ultimately lead to the elimination of intermediaries from electronic value chains. However, a careful analysis of the structure and functions of electronic marketplaces reveals a different picture. Intermediaries provide many value‐adding functions that cannot be easily substituted or ‘internalized’ through direct supplier–buyer dealings, and hence mediating parties may continue to play a significant role in the e‐commerce world. In this paper we provide an analysis of the potential roles of intermediaries in electronic markets and we articulate a number of hypotheses for the future of intermediation in such markets. Three main scenarios are discussed: the disintermediation scenario, in which market dynamics will favour direct buyer–seller transactions; the reintermediation scenario, in which traditional intermediaries will be forced to differentiate themselves and re‐emerge in the electronic marketplace; and the cybermediation scenario, in which wholly new markets for intermediaries will be created. The analysis suggests that the likelihood of each scenario dominating a given market is primarily dependent on the exact functions that intermediaries play in each case. A detailed discussion of such functions is presented in the paper, together with an analysis of likely outcomes in the form of a contingency model for intermediation in electronic markets.     

Exclusions and related trust relationships in multi-party fair exchange protocols

Some electronic commerce transactions are inherently performed between more than two parties. In this context, it is thus important to determine whether the underlying fair exchange protocols allowing the secure implementation of such transactions enable participants to exclude other entities from a protocol execution. This is an important point that has not been sufficiently addressed when analysing such kind of protocols, and that may be crucial for the successful accomplishment of multi-party electronic transactions. In this paper we define the properties related to exchange protocols and exclusions, study exclusion scenarios on two well-known multi-party fair exchange protocols and point out the implications that exclusions may have on the trust relationships between participants, and, more generally, on electronic commerce. Two new protocols more robust than existing multi-party fair exchange protocols are therefore proposed.     

Fair Trading Protocol with Offline Anonymous Credit Card Payment

Abstract

This paper proposes a fair trading protocol. The fair trading protocol provides an overall solution for a trading process with offline anonymous credit card payments.

With the exploding growth of electronic commerce on the Internet, the issue of fairness^1,2 is becoming increasingly more important. Fair exchange protocols have already been broadly used for applications such as electronic transactions,^3,4 electronic mails,^5,6and contract signing.⁷ Fairness is one of the critical issues in online transactions and related electronic payment systems. Many electronic payment systems have been proposed for providing different levels of security to financial transactions, such as iKP,⁸SET,⁹ NetBill,¹⁰ and NetCheque.¹¹ In a normal electronic commerce transaction, there is always a payer and a payee to exchange money for goods or services. At least one financial institution, normally a bank, should be present in the payment system. The financial institution plays the role of issuer for the payer and the role of acquirer for the payee. An electronic payment system must enable an honest payer to convince the payee of a legitimate payment and prevent a dishonest payer from using other unsuitable behavior. At the same time, some additional security requirements may be addressed based on the nature of trading processes and trust assumptions of the system. Payer, payee, and the financial institution have different interests and the trust between two parties should be as little as possible. In electronic commerce, the payment happens over an open network, such as the Internet, and the issue of fairness must be carefully addressed. There is no fairness for involved parties in the existing popular payment protocols. One target of this article is to address the fairness issue in the credit card payment process. In the existing credit card protocols, the financial institution that provides the credit card service plays the role of online authority and is actively involved in a payment. To avoid the involvement of financial institutions in normal transactions and to reduce running costs, some credit card-based schemes with offline financial authority have been proposed.¹² Another target of this article is to avoid the online financial institution for credit card service in normal transactions.     

The Dynamics of the Electronic Market: An Evolutionary Game Approach

The capabilities afforded by network technologies have facilitated the growth of electronic commerce. However, online frauds pose serious challenges to the further adoption of the electronic market. In order to promote trust and reduce transaction risks, various trusted third parties have emerged and new models have been proposed. Will people use the trusted third parties while conducting online transactions? How will the electronic market evolve? This research attempts to identify the different equilibria of the electronic market using an evolutionary game theoretic approach and to explore the best strategy to do transactions in the electronic market. Also, the work provides a theoretical justification to the emergence and necessity of trusted third parties for electronic transactions.     

Building trust in e-commerce

To increase confidence in commercial transactions over the Web where the transacting parties are invisible to each other, we need not just new protocols but also new transaction processes. One solution is to enlist a third party, referred to here as a trust service provider (TSP), to act as an Internet-based intermediary that assumes responsibility for a smooth transaction. The TSP is known and trusted by both customer and merchant and makes purchases on behalf of the one and conveys the goods on behalf of the other. The article describes a proposal for a trust Web model based on a distributed search algorithm and a network of trusted intermediaries that can establish a trusted channel through which terminal transacting parties deal virtually directly and risk-free with each other. The author has developed a CORBA-based implementation of the trust-path building algorithm and is currently testing its performance. The actual version of the system can be found at: http://faculty.uaeu.ac.ae/~atif/research/ecommerce/ec.html     

Accountability in electronic commerce protocols

In most commercial and legal transactions, the ability to hold individuals or organizations accountable for transactions is important. Hence, electronic protocols that implement commercial transactions must be designed to provide adequate accountability assurances for transacting parties. A framework is proposed for the analysis of communication protocols that require accountability, such as those for electronic commerce. This framework can be used to analyze protocol designs to detect accountability (or lack thereof). Arguments are presented to show that a heretofore unexplored property “provability” is pertinent to examining the potential use of communication protocols in the context of litigation, and in the context of audit. A set of postulates which are applicable to the analysis of proofs in general and the proofs of accountability in particular, are proposed. The proposed approach is more natural for the analysis of accountability than the existing belief logics (e.g., M. Burrows et al., 1990) that have been used in the past for the analysis of key distribution protocols. Some recently proposed protocols for electronic commerce and public key delegation are analyzed to illustrate the use of the new analysis framework in detecting (and suggesting remedies for eliminating) their lack of accountability, and in detecting and eliminating redundancies     

Verification of relational transducers for electronic commerce

Motivated by recent work of Abiteboul, Vianu, Fordham, and Yesha, we investigate the verifiability of transaction protocols specifying the interaction of multiple parties via a network. The protocols which we are concerned with typically occur in the context of electronic commerce applications and can be formalized as relational transducers. We introduce a class of powerful relational transducers based on Gurevich's abstract state machines and show that several verification problems related to electronic commerce applications are decidable for these transducers.     

An atomicity-generating protocol for anonymous currencies

Atomicity is necessary for reliable electronic commerce transactions. Anonymity is also an issue of great importance not only to designers of commerce systems, but also to those concerned with the societal effects of information technologies, providing atomicity and anonymity is not trivial. Reliable systems, which provide highly atomic transactions, offer limited anonymity. Many anonymous systems (Rivest and Shamir, 1996) do not offer anonymous reliable transactions (Yee, 1994). Three basic approaches have been used: secure hardware for trusted record-keeping (Brands, 1993), storage of identity information with trustees for conditional anonymity (Low et al., 1993) or by providing dispute resolution only with the removal of anonymity (Chaum, 1988). In this work, the problem of anonymous atomic transactions for a generic token currency is solved using distributed trust and with the assumption that any single party may be corrupt. Defined is a transaction to include the provision of information goods or a contract to deliver specified goods, allowing for the highest degree of atomicity. The cryptographic strength of the atomicity guarantee can be made to the user's specification on a per transaction basis. The atomicity-generating protocol includes provision for dispute resolution and anonymous refunds. Also illustrated, is that any electronic token currency can be made reliable with the addition of this atomicity-generating protocol     

A Transaction Cost Model of Electronic Trust: Transactional Return, Incentives for Network Security and Optimal Risk in the Digital Economy

Transaction cost economics can explain the mechanism by which network security technologies may reduce the interexchange costs between businesses in the supply chain and between businesses and customers in the digital economy. This paper develops the construct of technology-based electronic trust, where interpersonal, or “real” trust between people can be amplified and enhanced with the use of network security information technologies. The paper formally models an electronic commerce trust typology based on minimizing the cost of establishing trust in transactions, balanced against maximizing the potential user value from successfully completing transactions in the digital economy, suggesting that there is an optimal amount of acceptable risk in electronic commerce transactions. Sophisticated deployments of security information technologies may increase levels of interpersonal trust while lowering transaction costs in electronic commerce, thus promoting the long run development of neutral, interorganizational electronic markets and growth in the digital economy.     

Avoiding loss of fairness owing to failures in fair data exchange systems

Fair exchange between mutually distrusted parties has been recognized as an important issue in electronic commerce. However, the correctness (fairness) of the existing fair exchange protocols that use a Trusted Third Party (TTP) is based on the assumption that during an exchange there are no failures at any of the local systems involved in the exchange, which is too strong in many situations. This paper points out that (1) system failures may cause loss of fairness, and (2) most of the existing fair exchange protocols that use a TTP cannot ensure fairness in presence of system failures. This paper presents two categories of techniques, transaction-based approaches and message-logging-based approaches, to help develop data exchange systems that can recover from system failures without losing fairness.     

数字签名技术在电子商务中的应用研究

数字签名技术是保障电子商务安全的核心技术,在电子商务中可以实现交易双方的身份验证、数据完整性判断以及不可否认性服务。文章从数字签名原理、签名过程、存在的问题等方面对数字签名在电子商务中的应用展开研究。     

A peer-to-peer transaction authentication platform for mobile commerce with semi-offline architecture

Trusted third-party (TTP) based transaction authentication is traditionally applied to authenticate mobile commerce transactions. However, several issues can arise with this, including seller fraud, TTP performance bottlenecks, and the risk of operations being interrupted. A peer-to-peer mobile commerce transaction authentication platform (MCTAP) with a semi-offline transaction authentication mechanism is proposed in this work. In this, both buyer and seller mutually authenticate and sign the digital receipt for each other. The trusted transaction authentication center thus no longer needs to operate online transaction verification processes, and only has to deal with consumer disputes. MCTAP can raise the efficiency of transaction authentication and provide solutions for the one-way transaction notification systems adopted by most online shopping sites that may encounter seller fraud. The proposed solution is compared to other TTP-based and secure electronic transaction based transaction authentication mechanisms, and the results indicate that the MCTAP has the advantages of efficiency and a higher security level.     

一种改进的内存数据库封锁机制

事务之间的封锁协议一直是数据库领域中的研究重点。在典型的内存数据库系统中,由于事务通常都比较短小,执行速度快,因此事务之间通常采用类似单写多读这样较为简单的封锁控制协议,将不同事务近似串行地分别执行。在事务并发量较高但是相互之间数据交集不大的情况下,可以通过引入粗粒度意向锁和锁粒度变换的方式来进一步提高事务之间的并行程度,加速事务的整体执行,提高事务吞吐量和系统响应速度。     

Unenforced E-commerce transactions

Electronic commerce currently relies on traditional third party enforcement mechanisms that don't necessarily translate well to cyberspace. Chunking algorithms offer one possibility for unenforced transactions between self motivated agents. This method enables transactions in settings where the parties cannot identify each other, or where litigation is not viable. It also allows computational agents to be more autonomous by not requiring them to be strictly tied to the real world parties they represent. In cases where this type of unenforced exchange is possible, it is preferable to the strictly enforced mode of exchange because it saves enforcement costs (for example, litigation costs or operations costs of trusted third party intermediaries) and it is insensitive to enforcement uncertainties. The method is based on managing the exchange between two agents-a supplier and a demander-so that the gains from completing the exchange (cooperating according to a contract) at any point are larger for both agents than the gains from terminating it (defecting the exchange prematurely by vanishing)     

Who to Trust? Applying Trust to Social Commerce

Organizations have recognized the revenue potential for social commerce (purchasing products via social networks), but such transactions only comprise a small percentage of revenue. Companies have yet to determine the factors that contribute to social commerce failure. In social networking, trust is established when two parties have a history of trustworthy interactions. Acknowledging that social commerce represents a fundamentally different purchasing environment than typical business transactions, we examine the role of trust in determining consumers’ decisions to engage in social commerce for their purchases. We apply trust transfer theory to the social commerce context to assess whether trust in known entities can be transferred to business transactions facilitated through a social network with unknown parties. Using a field survey, we found that trust in the Internet and trust in firms significantly influence consumers’ trust and ultimately their intention to engage in social commerce. Implications for research and practice are discussed.     

电子商务协议研究综述

电子商务协议是电子商务实施的技术基础.对电子商务协议研究进行综述,包括电子商务协议设计的原则(如安全性、匿名性、原子性、不可否认性和交易规模)以及对若干著名电子商务协议的描述和分析.     

浅谈电子商务中的安全认证技术

由于我国长期受计划经济的影响,交易行为缺乏信用机制的支撑,已经成为制约市场经济健康发展,包括电子商务顺利进行的一个严重问题,因此要对交易各方的身份进行认证。保障电子商务交易安全比较成熟的技术,是以PKI(PublicKeyInfrastructure公共密钥基础设施)安全体系为基础,以CA中心为核心的信息加密和签名技术,通过使用签名、加密技术来实现交易双方传递信息的保密性、完整性、有效性和不可抵赖性。本文着手于电子商务正面临着安全问题,探讨了电子商务中的相关安全认证技术。为电子商务的深入推广提供了安全技术保障。     

一种可动态扩充的移动商务服务管理模型

移动商务是指利用移动终端设备进行无线商务交易的新型电子商务形式，它最大的特色和优势就是移动性。本文描述了一种支持多种无线协议，可动态升级的移动商务服务管理模型。这个模型基于JINI和WAP技术，可以高效地处理复杂的商务交易。     

基于SM2数字签名的区块链匿名密钥交换协议

区块链技术因其去中心化、匿名性、不可篡改、不可伪造等优点, 已经成为我国的一项前沿技术, 在各领域得到广泛的应用。虽然用户可利用区块链发布匿名交易, 有效隐藏交易双方的身份信息, 但双方交易完成后传输交易相关数据可能破坏匿名性。这是因为在数据传输过程中, 为了保证双方通信安全, 往往使用认证密钥交换协议认证双方身份, 计算会话密钥建立安全信道。由于传统的认证密钥交换协议涉及双方的长期公私钥对信息, 所以将泄露交易双方的身份信息。虽然区块链匿名密钥交换可基于交易双方的历史链上交易完成密钥交换, 有效保障交易双方的匿名性, 但现有区块链匿名密钥交换协议主要基于国外密码算法设计, 难以适用于国产区块链平台, 不符合我国密码核心技术自主可控的要求。为丰富国产商用密码算法在区块链匿名密钥交换方面的研究, 满足区块链交易后双方匿名安全通信的需求, 本文以 SM2 数字签名算法和区块链为基础, 构造非交互式和交互式两种区块链匿名密钥交换协议。并在 CK 安全模型中证明非交互式的协议满足会话密钥安全, 交互式的协议满足有前向安全性的会话密钥安全。最后通过理论分析和编程实现结果表明, 本文协议在没有比现有协议消耗更多的计算开销与通信代价的前提下, 可适用于国产化区块链平台。     

Experiences in developing a fair-exchange e-commerce protocol using common off-the-shelf components

Fair-exchange is an important property that must be ensured in all electronic commerce environments where the merchants and the customers are reluctant to trust each other. This property guarantees that none of the transacting parties suffer because of the fraudulent behavior of the other party in the transaction. In this paper, we describe our experiences in developing a new e-commerce protocol to address the problem of fair-exchange for digital products. The protocol is based on a novel cryptographic technique that we had proposed earlier. We show how to use common off-the-shelf software components to develop such a protocol.