• Journal of the Korea Society of Computer and Information
• /
• v.21 no.1
• /
• pp.91-99
• /
• 2016

A certificate revocation list(CRL) should be distributed quickly to all the vehicles in the network to protect them from malicious users and malfunctioning equipments as well as to increase the overall security and safety of vehicular networks. However, a major challenge is how to distribute CRLs efficiently. In this paper, we propose a novel Regional CRL distribution method based on the vehicle location registration locally to manage vehicle mobility. The method makes Regional CRLs based on the vehicles' location and distributes them, which can reduce CRL size and distribution time efficiently. According to the simulation results, the proposed method's signaling performance of vehicle's registration is enhanced from 22% to 37% compared to the existing Regional CRL distribution method. It's CRL distribution time is also decreased from 37% to 67% compared to the existing Full CRL distribution method.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.24 no.5
• /
• pp.795-807
• /
• 2014

Vehicular Ad hoc Network (VANET) has gone through a rich amount of research and currently is making its way towards the deployment. However, surprisingly it evolved to rather more applications and services-rich breed referred to as VANET-based clouds due to the advancements in the automobile and communication technologies. Security and privacy have always been the challenges for the think tanks to deploy this technology on mass scale. It is even worse that some security issues are orthogonally related to each other such as privacy, revocation and route tracing. In this paper, we aim at a specific VANET-based clouds framework proposed by Hussain et al. namely VANET using Clouds (VuC) where VANET and cloud infrastructure cooperate with each other in order to provide VANET users (more precisely subscribers) with services. We specifically target the aforementioned conflicted privacy, route tracing, and revocation problem in VANET-based clouds environment. We propose a multiple pseudonymous approach for privacy reasons and leverage the beacons stored in the cloud infrastructure for both route tracing and revocation. In the proposed scheme, revocation authorities after colluding, can trace the path taken by the target node for a specified timespan and can also revoke the identity if needed. Our proposed scheme is secure, conditional privacy preserved, and is computationally less expensive than the previously proposed schemes.

• The Journal of the Korea Contents Association
• /
• v.22 no.1
• /
• pp.292-309
• /
• 2022

Recently, with the development of interactive communication system, demands for video live streaming service has increased. Live streamers generate revenues from donations, but existing laws are inadequate to handle these donations. Problems arise when minors donate because they have the right of revocation. In the case of donations that request benefits in return, legal characteristics and results are different from unilateral donations. If minors exercise their right of revocation, live streamers must pay back without getting proper compensation for their services. In this paper, we detect the characteristics of bilateral contract in live streaming donation, indicate the harms that live streamers can get, examine precedents and donation processes focusing on cases when minors can not exercise the right of revocation due to deception, and propose revisions that can protect the streamers without invading minors' rights. Through academically identifying ambiguous legal situations and presenting dispute prevention procedures, this paper can bring positive impacts on the online industry.

• Proceedings of the Korea Information Assurance Society Conference
• /
• 2004.05a
• /
• pp.77-82
• /
• 2004

The notion of a certificate was introduced by Kohnfelder in his 1978 MIT bachelor's thesis. The idea, now common, was that a certificate is a digitally signed statement binding the key-holder's name to a public key. With the increasing acceptance of digital certificate, there has been a gaining impetus for methods to nullify the compromised digital certificates and enable the end user to receive this information before be trusts a revoked certificate. The problem of certificate revocation is getting more and more crucial with the development of wide spread PKIs. In this paper, we investigate recent trend of certificate revocation mechanism.

• Journal of the Korea Institute of Military Science and Technology
• /
• v.17 no.3
• /
• pp.358-363
• /
• 2014

In this paper, we present two constructions of the attribute-based broadcast encryption(ABBE) algorithm. Attribute-based encryption(ABE) algorithm enables an access control mechanism over encrypted data by specifying access policies among private keys and ciphertexts. ABBE algorithm can be used to construct ABE algorithm with revocation mechanism. Revocation has a useful property that revocation can be done without affecting any non-revoked uers. The main difference between our algorithm and the classical ones derived from the complete subtree paradigm which is apt for military hierarchy. Our algorithm improve the efficiency from the previously best ABBE algorithm, in particular, our algorithm allows one to select or revoke users by sending ciphertext of constant size with respect to the number of attributes and by storing logarithm secret key size of the number of users. Therefore, our algorithm can be an option to applications where computation cost is a top priority and can be applied to military technologies in the near future.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
• /
• v.31
• /
• pp.107-134
• /
• 2006

Enforcement of an arbitration award is an extremely important issue in arbitration. Arbitration, as a dispute settlement process, is rendered meaningless if it is not possible to enforce an award rendered by an arbitration tribunal. On the other hand, the present international arbitration system guided by the New York Convention and UNCITRAL Model Law is established on the dual supervision from the national courts. The nationality of the international arbitral award closely relates to the supervision of the national court, and the national court is entitled to decide the nationality of the international award in accordance with the conditions set in its own domestic law. The national court may set aside arbitral award made in its territory while the foreign court may refuge enforcement of foreign arbitral awards according to its own law and international convention to which it is a party. The conditions set in the Arbitration Law of the People's Republic of China are in agreement with those set in the UNCITRAL Model Law. The Chinese national court is entitled to set aside international awards made in China in accordance with the Chinese Law. The purpose of this paper is to clarify the Chinesr practice on the revocation of international commercial arbitral awards.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.9 no.5
• /
• pp.958-964
• /
• 2005

WLAN user authentication is mostly based on user password resulting in vulnerability to the notorious 'offline dictionary attack'. As a way around this problem. EAP-TTLS and PEAP protocols are increasing finding their way into WLANs, which are a sort of combination of password protocols and the TLS public-key protocol. This leads to the use of the public-key certificate of the WLAM authentication server, and naturally the concern arises about its revocation status. It seems, however, that any proper soulution has not been provided to address this concern. We propose a very efficent and proper solution to check the certificate revocation status.

• The KIPS Transactions:PartC
• /
• v.19C no.1
• /
• pp.63-70
• /
• 2012

To ensure privacy of individual information in remote healthcare service, health data should be protected through a secure technology such as encryption scheme. Only user who delegated decryption right can access to sensitive health data and delegator needs capability for revocating access privilege. Recently, in ubiquitous environment, CP-ABTD(Ciphertext-Policy Attribute-Based Threshold Decryption with Flexible Delegation and Revocation of User Attributes) which extends CP-ABE(Ciphertext-Policy Attribute-Based Encryption) has been proposed for these requirements. In this paper, we construct remote healthcare monitoring system with delegation and revocation capability for attribute in CP-ABTD. Finally, we analyze collusion attack between users in our system.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.12 no.4
• /
• pp.15-27
• /
• 2002

The purpose of this paper is to present both the specification of delta-CRL and the polices for delta CRL in order to solve the problem involved in issuing and maintaining the certificate revocation lists for the mobile communication network. If the user request to revoke the certificate issued by certification authority, the certification should be revoked and listed up in the certificate revocation list. In general, the certificate revocation list is issued regularly. Therefore PKI application should download the CRL and prove the validity of CRL. The traffic size of the exchanged traffic should be reduced for the mobile communication environment. The result if this paper can be used for the mobile communication various environments to reduce the size of CRL.

• The Korean Society of Law and Medicine
• /
• v.19 no.1
• /
• pp.113-142
• /
• 2018

In recent years, there have been opinions in which physicians are liable to the revocation of their medical license if they are sentenced to above a certain level for criminal charges regardless of the types of offenses. Accordingly, a revised bill of law was submitted in the National Assembly, and related discussions are thus expected to commence. Considering the morality and ethics or the level of the rule of law that the general public expects of physicians, as well as the license revocation system in other professional sectors, it is assessed that medical license revocation due to criminal convictions of physicians is appropriate to some degree. However, if a poorly devised system is established based on unrefined inferences or emotional judgements, unexpected side-effects are likely to arise. With regard to serious criminal acts that society generally perceives as unacceptable, it can be assessed that the revocation of physicians' licenses would appropriately protect the general public from threats. However, given the life-saving characteristics of high-risk medical practices, higher malpractice exposures, and social values, it is difficult to assess charges of professional negligence resulting in death(or in injury) and minor offences in the same manner as anti-social criminal offences are handled. Physicians need to be treated the same as any other professions. At the same time, they are engaged in administering medical treatment to patients in the face of great risks as professionals. Under the circumstances, a discussion on the introduction of a more specific and empirical system is needed by considering the intrinsic characteristics of medical treatment and the need for an equitable health and medical policy. Accordingly, based on the above judgment and perception, this study explores the code of ethics for physicians and medical license revocation related to criminal offences at home and abroad, and examines various legislative alternatives appropriate for the Republic of Korea. In doing so, the purpose of the study is to contribute to the development of a reasonable system for handling criminal offences by physicians.