• ETRI Journal
• /
• v.39 no.1
• /
• pp.135-144
• /
• 2017

Recently, mobile phones have been recognized as the most convenient type of mobile payment device. However, they have some security problems; therefore, mobile devices cannot be used for unauthorized transactions using anonymous data by unauthenticated users in a cloud environment. This paper suggests a mobile payment system that uses a certificate mode in which a user receives a paperless receipt of a product purchase in a cloud environment. To address mobile payment system security, we propose the transaction certificate mode (TCM), which supports mutual authentication and key management for transaction parties. TCM provides a software token, the transaction certificate token (TCT), which interacts with a cloud self-proxy server (CSPS). The CSPS shares key management with the TCT and provides simple data authentication without complex encryption. The proposed self-creating protocol supports TCM, which can interactively communicate with the transaction parties without accessing a user's personal information. Therefore, the system can support verification for anonymous data and transaction parties and provides user-based mobile payments with a paperless receipt.

• Journal of IKEEE
• /
• v.19 no.4
• /
• pp.617-624
• /
• 2015

In this paper, an adult authentication system based on authentication certificate was designed and implemented using smartphone and near-field communication. It has three advantages. First, it achieves easy, convenient, and fast authentication by using smartphone and near-field communication. Second, it achieves extremely high security and reliability by exploiting authentication certificate. Third, it achieves extremely low risk of personal information leakage by generating and sending only virtual identification code. Finally, it has a proper legal basis by Digital Signature Act. It consists of adult authentication module, near-field communication control module, policy server module, and database server module. A prototype of the proposed system was designed and implemented, and it was verified to have correct operation.

• Journal of Internet Computing and Services
• /
• v.7 no.3
• /
• pp.83-91
• /
• 2006

In this paper, we improved a cryptography system model based on the secure initial authentication public key with PKINIT of authentication and key recovery protocol. It is applied to all fields of cryptography system using certificate. This study presents two mechanisms to authenticate between member users. The first mechanism is initial authentication and distribution of session key by public key cryptography based on certificate between entity and server, and the second mechanism is a key recovery support protocol considering loss of session key in the secure communication between application servers.

• IEIE Transactions on Smart Processing and Computing
• /
• v.3 no.5
• /
• pp.298-305
• /
• 2014

In this study, a novel Randomly Shifted Certification Authority Authentication protocol was used in ad hoc networks to provide authentication by considering the MAC layer characteristics. The nodes achieve authentication through the use of public key certificates issued by a CA, which assures the certificate's ownership. As a part of providing key management, the active CA node transfers the image of the stored public keys to other idle CA nodes. Finally the current active CA randomly selects the ID of the available idle CA and shifts the CA ownership by transferring it. Revoking is done if any counterfeit or duplicate non CA node ID is found. Authentication and integrity is provided by preventing MAC control packets, and Enhanced Hash Message Authentication Code (EHMAC) can be used. Here EHMAC with various outputs is introduced in all control packets. When a node transmits a packet to a node with EHMAC, verification is conducted and the node replies with the transmitter address and EHMAC in the acknowledgement.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.5C
• /
• pp.737-749
• /
• 2004

Kerberos authenticates clients using symmetric-key cryptography, and supposed to Oust other systems of the realm in distributed network environment. But, authentication and authorization are essential elements for the security. In this paper, we design an efficient and secure authentication/authorization mechanism by introducing the public/private-key and installing the proxy privilege server to Kerberos. In the proposed mechanism, to make a system more secure, the value of the session key is changed everytime using MAC(message authentication code) algorithm with the long-term key for user-authentication and a random number exchanged through the public key. Also, we reduce the number of keys by simplifying authentication steps. Proxy privilege server certifies privilege request of client and issues a privilege attribute certificate. Application server executes privilege request of client which is included a privilege attribute certificate. Also, a privilege attribute certificate is used in delegation. We design an efficient and secure authentication/authorization algorithm with Kerberos.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.13 no.6
• /
• pp.97-106
• /
• 2003

The important factor in Public-Key Infrastructure is the authentication to correspondent. We receive the digital certificate for authentication between each other, and then we check the existence of validity on the certificate by Certification Revocation List(CRL). But, To use CRL is the scheme used in offline status. So, it is impossible to refer to the latest information and the CRL scheme which is used after downloading is variously unsuitable to getting bigger of the CRL size as time goes on. Therefore, we prefer OCSP(Online Certificate Status Protocol) used in online to CRL used in offline. Consequently, we propose the scheme which provides the request of fast verification in case of requesting the verification on the certificate by owning the same update information to Certificate Registry and distributed OCSP.

• Journal of Internet Computing and Services
• /
• v.9 no.4
• /
• pp.69-77
• /
• 2008

I propose adding users’Media Access Control (MAC) addresses to standard X.509 certificates to provide more secure authentication. The MAC address can be added by the issuing Certification Authority (CA) to the "extensions" section of the X.509 certificate. I demonstrate that when two users with MAC address information on their digital certificates communicate, the MAC address on the first user’s certificate can be easily verified by the second user. In this way, security can be improved without markedly degrading system performance and the level of initial trust between participants in virtual communities will be improved.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.8
• /
• pp.1466-1477
• /
• 2016

Public key infrastructure(PKI), principle technology of the certificate, is a security technology providing functions such as identification, non-repudiation, and anti-forgery of electronic documents on the Internet. Our government and financial organizations use PKI authentication using ActiveX to prevent security accident on the Internet service. However, like ActiveX, plug-in technology is vulnerable to security and inconvenience since it is only serviceable to certain browser. Therefore, the research on HTML5 authentication system has been conducted actively. Recently, domestic bank introduced PKI authentication complying with web standard for the first time. However, it still has inconvenience to register a certification on each website because of same origin policy of web storage. This paper proposes the certificate based SSO protocol that complying with web standard to provide user authentication using certificate on several sites by going around same origin policy and its security proof.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.24 no.5
• /
• pp.931-939
• /
• 2014

The Web or Mobile channel of previous Web access authentication system for a payment only provides the authentication of remote users, and does not provide the authentication between a user and a bank/financial institution. Therefore, this paper proposes the Transaction Certificate Mode(TCM) for a payment which can preserve the mutual authentication between a user and a bank/financial institution for Web-based payment systems. The proposed system has designed for wireless network instead of Secure Electronic Transaction (SET) designed for wired electronic transaction. In addition, this system with TCM is able to support an account-based transaction for wireless networks instead of a disadvantage of SET such as a card-based transaction for wired networks. Therefore, customers can check their balances without logging on their bank's web site again due to mutual authentication between a customer and his bank/financial institution.

• ETRI Journal
• /
• v.38 no.4
• /
• pp.724-734
• /
• 2016

To achieve confidentiality, integrity, authentication, and non-repudiation simultaneously, the concept of signcryption was introduced by combining encryption and a signature in a single scheme. Certificate-based encryption schemes are designed to resolve the key escrow problem of identity-based encryption, as well as to simplify the certificate management problem in traditional public key cryptosystems. In this paper, we propose a new certificate-based signcryption scheme that has been proved to be secure against adaptive chosen ciphertext attacks and existentially unforgeable against chosen-message attacks in the random oracle model. Our scheme is not based on pairing and thus is efficient and practical. Furthermore, it allows a signcrypted message to be immediately verified by the public key of the sender. This means that verification and decryption of the signcrypted message are decoupled. To the best of our knowledge, this is the first signcryption scheme without pairing to have this feature.