Magyar Kutatók 8. Nemzetkzi Szimpóziuma 8

Abstract: In this paper we propose a new, fault tolerant on-line EPS. After the analysis of all the possible failure scenarios, for each case we propose solutions based on roll-back and recovery mechanism (repetitions, time-out, acknowledge messages, logs,

Magyar Kutatók 8. Nemzetközi Szimpóziuma

8th International Symposium of Hungarian Researchers on Computational Intelligence and Informatics Analysis of an Electronic Payment System Using Simulation

Otto Poszet, Ovidiu Novac, Stefan Vári-Kakas

Department of Computer Science, Faculty of Electrical Engineering and

Information Technology, University of Oradea

Univeritatii Str., nr.1., Oradea, Romania

E-mail: poszet@uoradea.ro; ovnovac@uoradea.ro; vari@uoradea.ro

Abstract: In this paper we propose a new, fault tolerant on-line EPS. After the analysis of all the possible failure scenarios, for each case we propose solutions based on roll-back and recovery mechanism (repetitions, time-out, acknowledge messages, logs, resending, synchronizations). Based on the Monte-Carlo method, we realized a simulation of system behavior, in order to obtain the EPS’s correct service rate vs. the messages loss rate between client-bank and shop-bank. Based on this simulation we concluded the increase of the success rate of transactions in the fault tolerant case vs. the un-tolerant case.

Keywords: Electronic Payment System, data security, fault tolerance, Monte-Carlo simulation

1 Introduction

The main difference between an on-line and an off-line Electronic Payment System (EPS) is that the payment protocol in the case of the on-line systems is monitored, checked and authorized by a Trusted Third Party (e.g. the bank). In the off-line systems, the payment protocol is executed only between the client and the shop, without a Trusted Third Party. So, this kind of EPS-s can guarantee more freedom for clients, as the on-line EPS-s, but their main disadvantage is that the fraud detection can be made only after the payment, in the deposit protocol. This is the reason, why the on-line payment systems are more often used, as the off-line systems. We can say that in the on-line EPS-s is ensured the preventive integrity and not only the degradation integrity (off-line case, increased security).

There are a lot of on-line systems implemented, and the main goal in development was to ensure security. Their study demonstrated that the real systems have very few embedded fault tolerance mechanisms, or they have not at all. We propose a new on-line EPS, which is similar to the existing EPS-s (e.g. Visa, PayPal), but provides fault tolerant mechanisms.

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Abstract: In this paper we propose a new, fault tolerant on-line EPS. After the analysis of all the possible failure scenarios, for each case we propose solutions based on roll-back and recovery mechanism (repetitions, time-out, acknowledge messages, logs,

O. Poszet et al.

Analysis of an Electronic Payment System Using Simulation

2 Architecture of the Proposed, Fault-Tolerant, On-

Line EPS

The proposed, on-line EPS uses transactions between three kinds of entities: clients (payers), electronic shops (payees) and the bank (Trusted Third Party). The

architecture of the proposed system is shown in Figure 1.

Step5:

Bank

tep6: acknowledge Client

Virtual shop

Step2:

Product order

Figure 1

The architecture of the proposed, on-line EPS

The chronological order of the events in the case of an on-line shopping is:

1 The client, using a web browser, accesses the authorized site of the bank,

section ‘accredited virtual shops’, and chooses a shop, using the link obtained from the bank.

2 The client selects some products or services from the shop, using his shopping

cart, and launches the payment process.

3 The shop collects some information for the product delivery (e.g. address),

generates a transaction’s ID, saves all the data in a database, and redirects the client’s browser to the bank site. The shop sends (encrypted) to the bank the transaction’s ID, the amount of money and the shop’s name to lunch a payment.

326

Abstract: In this paper we propose a new, fault tolerant on-line EPS. After the analysis of all the possible failure scenarios, for each case we propose solutions based on roll-back and recovery mechanism (repetitions, time-out, acknowledge messages, logs,

Magyar Kutatók 8. Nemzetközi Szimpóziuma

8th International Symposium of Hungarian Researchers on Computational Intelligence and Informatics 4 The bank asks the client to fill out a secure form for authentication: name,

credit card number, date of issue, expiry date and password.

5 Based on this data, the bank verifies the identity of the client, the validity of

the card, the sum of money in the account, and asks the client to confirm the money transfer to the shop’s account.

6 If the bank receives the acknowledge from the client, the bank transfers the

requested and confirmed amount of money in the account of the shop, saves the transaction in his data base, and sends an acknowledge to the shop, using a message signed digitally by the bank with the bank’s secret key.

7 The shop delivers the paid product or service to the client.

8 The shop will save the received acknowledge message signed by the bank, and

this message can be used later as a confirmation of the payment.

9 The client can verify every time his personal payment archive accessing the

bank web site, and using his login name and password.

The proposed system ensures anonymity, because the client must not give his real personal data to the shop, for example his name, or his credit card number. The client launches the payment using the bank and only …… 此处隐藏：14418字，全部文档内容请下载后查看。喜欢就下载吧 ……