• The KIPS Transactions:PartC
• /
• v.14C no.4
• /
• pp.321-330
• /
• 2007

This paper proposes a two-phase server login authentication system by XML-Signature schema extension to protect server's information resources opened on network which offer various web contents. A proposed system requests and publishes XML-based certificate through on-line, registers certificate extension information provided by CA(Certification Authority) to XCMS(XML Certificate Management Server), and performs prior authentication using user's certificate password. Then, it requests certificate extension information added by user besides user's certificate password and certificate extension information registered in XCMS by using SOAP message, and performs posterior authentication by comparing these certificate extension information. As a result, a proposed system is a security reinforced system compared with existing systems.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.14 no.4
• /
• pp.25-37
• /
• 2004

A certificate is expected to use for its entire validity period. However, a false information record of user and compromise of private key may cause a certificate to become invalid prior to the expiration of the validity period. The CA needs to revoke the certificate. The CA periodically updates a signed data structure called a certificate revocation list(CRL) at directory server. but as CA updates a new CRL at directory server. the user can use a revoked certificate. Not only does this paper analyzes a structure of CRL and a characteristic of certificate status conviction, OCSP method but also it proposes a new certificate status verification method adding an observer information in handshake process between user and server.

• Journal of the Korea Society of Computer and Information
• /
• v.21 no.10
• /
• pp.63-68
• /
• 2016

Recently, Biometrics is being magnified than ID or password about user authentication. However, unlike a PIN, password, and personal information there is no way to modify the exposure if it is exposed and used illegally. As FIDO(Fast IDentity Online) than existing server storing method, It stores a user's biometric information to the user device. And the user device authentication using the user's biometric information, the user equipment has been used a method to notify only the authentication result to the server FIDO. However, FIDO has no mutual authentication between the user device and the FIDO server. We use a Certificate Authority in order to mutually authenticate the user and the FIDO server. Thereby, we propose a more reliable method and compared this paper with existed methods about security analysis.

• Journal of Internet Computing and Services
• /
• v.5 no.2
• /
• pp.33-40
• /
• 2004

PKI(Public Key Infrastructure) issues a certificate for providing Integrity of public key. and it Inspects the validity by downloading CRL(Certificate Revocation List) for checking the validity of certificate. But. it imposes a burden on processing of certificate due to Increase of user and the size of CRL, Lately, OCSP(Online Certificate Status Protocol), which examines the validity on online, is published as an alternative plan. But, it makes a problem due to concentration of just one certificate repository, Accordingly we propose the scheme that OCSP server is arranged in distributed area and then the information is safely transmitted to OCSP server.

• The Journal of the Korea Contents Association
• /
• v.5 no.2
• /
• pp.95-105
• /
• 2005

As a research on PKI is being very popular, the study relating to certificate status validation is being grown with aim to reduce an overhead of the protocol and to provide an efficient operation. The OCSP of the standard protocol related to the study enables applications to determine the revocation state of an identified certificate. However, the OCSP server can not service millions of certificate status validation requests from clients in a second on E-commerce because of the computational time for signature and verification. So, we propose the Real-time Certificate Status Validation Protocol(RCSVP) that has smaller computational time than OCSP. RCSVP server reduce the computational time of certificate status validation using hash function and common secret value. Also RCSVP client does not need the computational time of certificate verification to acquire the public key from an identified certificate. Therefore, the proposed protocol enables server to response millions of certificate status validation requests from clients in a second on E-commerce.

• Journal of the Korea Computer Industry Society
• /
• v.5 no.5
• /
• pp.721-728
• /
• 2004

OCSP (Online Certificate Status Protocol) server which checks the certificate status provides the real time status verification in the PKI (Public Key Infrastructure) system which is the essential system of certificate. However, OCSP server need the message authentication with the server and client, so it has some shortcomings that has slow response time for the demands of many clients concurrently and has complexity of the mathematical process in the public encryption system. In this research, simulation model of the certificate status vertification server is constructed of the DEVS (Discrete EVent system Specification) formalism. This sever model is constructed to practice the authentication with hash function when certificate is checked. Simulation results shows the results of increase of the certificate status verification speed and decrease of the response time to the client.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.13 no.1
• /
• pp.59-67
• /
• 2003

PMI(Privilege Management Infrastructure) certificates as well as Public-Key certificates must be validated before being used. Validation for a PMI certificate requires PMI certificate path validation, and PKC(Public-Key Certificate) path validations for each entity in the PMI certificate path. This validation work is quite complex and burdened to PMI certificate verifiers. Therefore, this paper suggests a delegated PMI certificate validation that uses specialized validation server, and defines a validation protocol which is used between validation server and client.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.30 no.4A
• /
• pp.304-311
• /
• 2005

OCSP has specific characters which can suspend, close, and correct in real time. But, as more clients use the OCSP server verification, more updated information is needed, which can lead to jamming in the OCSP server. To apply this technique of Distributed OCSP server so as to reduce the certificate verification OCSP from jamming. Also, the Distributed OCSP server will solve the problems of the intensive central structure. Simulation results show that the average reply time of certificate verification request and server load are reduced in the case using distributed OCSP. In addition to this advantage, resource distribution and fault tolerance are acquired because of multiple OCSP.

• 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 the Korea Institute of Information Security & Cryptology
• /
• v.13 no.1
• /
• pp.99-113
• /
• 2003

As a research on PKI(Public Key Infrastructure) is being very popular, the study relating to certificate status and path validation is being grown with aim to reduce an overhead of the protocol and to provide an efficient operation. But in spite of a lot of related research there is still almost no protocol that we can use for real-time based client-server environment with large scale like internet banking. In this paper, we shows that the existing standards or protocols are not suitable to be used for such a real-time based client-server environment with large scale, and then proposes an efficient certificate status and path validation system.