Hyoseung Kim

Attribute-Based Encryption for Commercial Content Distribution

There is growing need for digital content distribution system in the IPTV market so that the content providers can make digital content available to users in a controlled manner. Digital right management technologies allow being able to restrict access to a content giving an access policy so content is available only to fair user. However, such a previous system has some problem in terms of management of user’s access information and computational cost for server. One of solutions to overcome the abovementioned problem is attribute-based encryption scheme providing access control to the encryption system. In this paper, we propose attribute based encryption scheme which is useful in contents distribution for IPTV, DVD and access control in encrypted file systems. Our attribute based encryption scheme allows for AND, OR, threshold and wildcard operations over attribute. Furthermore, our scheme achieves 0(1) pairings for decryption, regardless of any number of attributes.

An Efficient ID-Based Mutual Authentication Secure against Privileged-Insider Attack

Many people conveniently can use Internet banking, online shopping and e-payment. Those services need low computation load and secure protocol against various attacks for using them in mobile environment. As a result of active research for this topic, Elliptic Curve Cryptography (ECC) is used to reduce computation load and various protocols that are based on Discrete Logarithm Problem (DLP) and Computational Diffie Hellman Problem (CDH) have been presented. But some protocols are vulnerable to privileged-insider attack. This paper introduces an efficient ID-based mutual authentication with key agreement protocol by solving problems of the previous, so it is strong secure against all known attacks, especially privileged-insider attack.

mvSERS: A Secure Emergency Response Solution for Mobile Healthcare in Vehicular Environments

Mobile healthcare (m-Healthcare) is a burgeoning electronic healthcare segment, and is designed to improve the quality and safety of healthcare by combining advanced mobile communication technologies with eHealth systems. The objective of m-Healthcare is to provide ubiquitous healthcare services; however, its application in the life-critical vehicular environment has thus far received limited attention. In this paper, we propose mvSERS, a secure emergency response solution for vehicular environments. Based on existing advanced technologies, mvSERS facilitates secure realtime monitoring and rapid emergency responses. In particular, mvSERS utilizes dual emergency response centers to effectively process different levels of emergencies. We conduct a comprehensive security analysis to demonstrate that mvSERS meets fundamental security requirements, such as data confidentiality, authenticity and integrity; we also verify that it resists replay attacks, man-inthe-middle attacks, identity theft and forgery attacks. Simulated experiments are also performed to demonstrate that mvSERS achieves good performance in terms of reducing storage costs, computational complexity and communication overhead.

Less Communication: Energy-Efficient Key Exchange for Securing Implantable Medical Devices

Implantable medical devices (IMDs) continuously monitor the condition of a patient and directly apply treatments if considered necessary. Because IMDs are highly effective for patients who frequently visit hospitals (e.g., because of chronic illnesses such as diabetes and heart disease), their use is increasing significantly. However, related security concerns have also come to the fore. It has been demonstrated that IMDs can be hacked—the IMD power can be turned off remotely, and abnormally large doses of drugs can be injected into the body. Thus, IMDs may ultimately threaten a patient’s life. In this paper, we propose an energy-aware key exchange protocol for securing IMDs. We utilize synchronous interpulse intervals (IPIs) as the source of a secret key. These IPIs enable IMDs to agree upon a secret key with an external programmer in an authenticated and transparent manner without any key material being exposed either before distribution or during initialization. We demonstrate that it is difficult for adversaries to guess the keys established using our method. In addition, we show that the reduced communication overhead of our method enhances battery life, making the proposed approach more energy-efficient than previous methods.

An Improved Fuzzy Attribute-Based Authentication

Authentication protocol is variously designed by attribute-based encryption. In some case, there is situation that need the authentication with revealed ID of users. Zhu et al present attribute authentication protocol containing ID. But their protocol did not have security under collusion attack and impersonation attack. In this paper, we propose enhanced protocol from Zhu et al.s protocol. The protocol was constructed based on fuzzy attribute-based authentication protocol on the basis of Lagrange polynomial interpolation. Our protocol has some good features which are safer than existing protocol. We also showed that our protocol has sufficient security under assumption of specific attack situations. So, we expect this protocol will be widely used to various environment which needs the multi-factor identifications.

An Implementation Method of HB-Family Light-weight Authentication for Device Authentication between ECU

The In-Vehicle-Networking(IVN) of modern cars is constituted by an small electronic control device called ECU. In the past, there was no way to be able to access the IVN of a driving car. so IVN has been recognized as a closed environment so there is no need to exist authentication protocol between devices which are to configure the internal network and to communicate with other devices. However, constant improvements made it possible to access the IVN in many different ways as the communication technology evolves. This possibility created a need for device authentication in IVN. HB-Family are representative authentication schemes in RFID environment which has similar restrictions to IVN. In this paper, we propose an implementation method of HB-Family for device authentication between ECU considering ECU has low computing power and the message field of CAN protocol has restricted size of 8 bytes. In order to evaluate the efficiency and availability of the authentication schemes adopted our method, we have evaluated the performance based on DSP-28335 device. Further, it was possible to improve the efficiency rate of at lest 10%, up to 36%, and we then analyze this result in various aspects of the IVN.

Threshold Identity-Based Broadcast Encryption from Identity-Based Encryption

In threshold identity-based encryption, a sender encrypts a message under identities of a pool of users and assigns a threshold t to the ciphertext, and sends the resulting ciphertext to these users. The cooperation of at least t users among them is required to decrypt the given ciphertext. We propose a construction method for threshold identity-based broadcast encryption from any existing identity-based encryption.