Im Young Jung

Enhanced Security for Online Exams Using Group Cryptography

While development of the Internet has contributed to the spread of online education, online exams have not been widely adopted. An online exam is defined here as one that takes place over the insecure Internet, and where no proctor is in the same location as the examinees. This paper proposes an enhanced secure online exam management environment mediated by group cryptography using remote monitoring and control of ports and input. The target domain of this paper is that of online exams for math or English contests in middle or high school, as well as exams in online university courses with students in remote locations.

Enhancing QoS and Energy Efficiency of Realtime Network Application on Smartphone Using Cloud Computing

This paper proposes a scheme to enhance energy efficiency and QoS of real time network applications on smart phone. The scheme reduces energy consumption and increases the successful interaction rate between the client at smart phone and the busy server of real time network application by deploying a surrogate of the client at smart phone in cloud computing environment. All interactions among the client at smart phone, the application server and the surrogate in the cloud are controlled by tokens. The proposed scheme considers security as well as energy waste in the cloud.

HVEM datagrid: implementation of a biologic data management system for experiments with high voltage electron microscope

This paper proposes High Voltage Electron Microscope (HVEM) DataGrid for biological data management. HVEM DataGrid allows researchers to share the results of their biological experiments using HVEM, so that they can analyze them together to perform good research. The proposed system is for people whose primary work is to access HVEM, to obtain experimental results for biological samples and to store or retrieve them on HVEM DataGrid. The architecture of the HVEM Grid[3] is designed to materialize all the necessary conditions in allowing the user 1) to control every part of HVEM in a fine-grained manner, 2) to check the HVEM and observe various states of the specimen, 3) to manipulate their high resolution 2-D and 3-D images, and 4) to handle the experimental data including storing and searching them. HVEM DataGrid, a subsystem of the HVEM Grid system, is to provide a simple web-based controlling method for remote biological data.

Multi-layer Trust Reasoning on Open Provenance Model for E-Science Environment

Trust for the data created and processed on e-Science environment can be estimated with provenance. The information to form provenance, which says how the data was created and reached its current state, increases as data evolves. It is a heavy burden to trace and verify the massive provenance along the history of data in order to trust data. On the other hand, it is another issue how to trust the verification of data with provenance assuming that the provenance is believable. This paper proposes the property-based trust reasoning which cuts down the overhead to track the history and the origin of data with provenance by semantic path on Open Provenance Model(OPM). Also, the domain-based trust reasoning is adopted, which uses the domain specialty of e-Science environment. The two trust reasonings form the multi-layer trust reasoning. The effectiveness of the proposal is shown by quantitative analysis of overhead reduction as well as by qualitative analysis of trust reasoning.

Provenance security guarantee from origin up to now in the e-Science environment

The e-Science environment provides science researchers with an online laboratory. Objects, including research data and related information, are transferred and shared in electronic form easily in an e-Science environment. Provenance, as a complete record of the changes applied to an object, provides a basis to trust an object. At this point, this paper proposes the Provenance Security from Origin up to Now (PSecON) scheme to solve the problem of how to trust provenance which is used for object trust. Through PSecON, while tracing the real source of an object transferred between e-Science environments, researchers can ensure the integrity of the object and its provenance, and confirm its actual origin. PSecON satisfies transparent audits and audit availability as well as the confidentiality and privacy of data and its provenance. These are provided by the history pool as an open board and by information hashing, respectively. PSecON supports forgery prevention and detection for provenance as well via two-way certification. Moreover, PSecON is scalable and ensures efficient and fast tracking of provenance. Based on the detailed description of PSecON in the e-Science domain, this paper demonstrates the soundness of PSecON to ensure provenance security and its easy applicability to real-world systems by analyzing the time, space and transmission overhead.

A Stateful Web Service with Scalable Security on HVEM DataGrid

Web Service has its characteristic of statelessness. But, many applications on Grid need the stateful services. The advanced search on HVEM DataGrid is one example. The search service provides a multi-depth search and an associated search. The service should trace the search states and provide the access control as well as the service security in the search process. In addition, we should remember that the Web Services or the resources can stretch multiple Virtual Organization(VO)s and Certificate Authority(CA)s. In this paper, we propose a secure stateful Web Service to satisfy the requirements stated. We describe the Stateful Web Service with the Scalable Security (S3WS) as its service environment and its protocol in detail. Through the security proof, the scalability analysis and the estimation of performance and overhead, we demonstrate the stateful Web Service proposed to be secure and light weight enough to be realistic.

An efficient and reliable message passing by mobile agent

For messages with a variety of characteristics, unicasting, multicasting and broadcasting do not on the whole ensure the optimum efficiency. For the transfer of a message to many receivers, we propose to adopt our messenger agent based on the mobile agent paradigm instead of sticking to the three main protocols. Its autonomy and asynchronous message delivery handle this case in a more efficient and reliable manner compared with unicasting, which is a sender-based message transfer protocol like ours. Of course, we must pay for the creation, migration, and management of it. However, we have justified the employment of our messenger agent by proving the profit from it to overcome the cost. We have considered the buffer requirements at gateways to defend the given drop ratio, the single node delay and the total delay for the entire message delivery path per packet.

A Dynamic Bridge for Data Sharing on e-Science Grid Implementing Web 2.0 Service

This paper proposes a dynamic bridge for e-Science Grid, implementing Web 2.0 service in order to share experimental data effectively.An e-Science Grid has been established as a cyber laboratory for the users with a special research purpose on science. As an open space, e-Science Grid is expected to stimulate the collaborative researches and the cross domain ones. These research trends need a more efficient and convenient data service satisfying the science researchers. A dynamic bridge designed based on HVEM DataGrid, satisfies the users’ requirements for the data sharing on e-Science Grid effectively. It supports a data tagging service in order for HVEM DataGrid to be utilized more extensively without any modification of the existing Grid architecture or services. Moreover, it can be adopted and deleted easily without any effect to the legacy Grid. With the legacyinterface to access data in e-Science Grid, the data tags endow the Grid with the flexibility for data access. This paper evaluates the usefulness of the dynamic bridge by analyzing its overhead and performance.

A Cost-Effective Guarantee of Security and Scalability on HVEM DataGrid with Active Disk

This paper proposes an efficient, scalable and secure (ESS) data management system on HVEM datagrid to ensure the security for data access as well as to balance the load of data intensive processing using active disks. When authentication and authorization are managed by a storage manager or a server on datagrid, if an attacker succeeds in assaulting the entity, he can access to the data on the disks and manipulate it easily. In addition, as data increases, so does the overhead of its processing as much. One example is to search files by image matching. So, we can let the disk take charge of the matching and the cryptographic processing for authentication, authorization and encryption/decryption beyond the simple role to keep data. Through evaluation, we show that the ESS system using disk intelligence can be very advantageous in security and cost-effectiveness.

An efficient and transparent transaction management based on the data workflow of HVEM DataGrid

This paper proposes an efficient and transparent transaction management on HVEM DataGrid. HVEM DataGrid has its data workflow which defines the precedence of the data to be saved. The precedence drives many states in a transaction for data management on HVEM DataGrid. We divide the transaction into several sub-transactions according to the states and classify the sub-transactions. Through the transaction hierarchy and parallelism, large image data can be uploaded to HVEM DataGrid efficiently and safely. The transaction management guarantees effective garbage collection as well. The garbage collection is important in HVEM DataGrid because it allows incomplete data insertion and update; it is not easy to decide whether the experimental results and their metadata are stored completely or not. Also, as shared storage system, HVEM DataGrid is composed of heterogeneous storages such as DBs and file storages. But, the transaction to save data to the datagrid requires to access those storages at the same time. And, the access should be transparent to users. The transaction hierarchy can solve the simultaneous access and satisfy these requirements. We will show the proposed scheme to be sound through analysis and to be effective by performance evaluation and overhead estimation. This paper shows that HVEM DataGrid can be a good model of e-Science datagrid through the efficient and transparent transaction scheme across many heterogeneous storages.