Joon-Min Gil

• Doctor of Philosophy
• Professor at Jeju National University

Recently, most of the universities in Korea is doing a lecture evaluation survey every semester. The continuous quality improvement (CQI) report is one of the most popular lecture evaluation service systems, which able to summaries and analysis the mean of evaluation reports. Since 2016, education office allows CQI system to begin uploads and analy...

Software-defined wide-area network (SD-WAN) is gaining strong momentum as distributed cloud evolves. The new cloud infrastructure requires novel and innovative network technologies based on virtualization, automated resource (e.g., datacenters, VMs, networks) convergence, ultra-high data-forwarding performance, and strict network security. To meet...

Many artificial intelligence applications often require a huge amount of computing resources. As a result, cloud computing adoption rates are increasing in the artificial intelligence field. To support the demand for artificial intelligence applications and guarantee the service level agreement, cloud computing should provide not only computing res...

Recent development of distributed cloud environments requires advanced network infrastructure in order to facilitate network automation, virtualization, high performance data transfer, and secured access of end-to-end resources across regional boundaries. In order to meet these innovative cloud networking requirements, software-defined wide area ne...

Since cloud computing provides computing resources on a pay per use basis, a task scheduling algorithm directly affects the cost for users. In this paper, we propose a novel cloud task scheduling algorithm based on ant colony optimization that allocates tasks of cloud users to virtual machines in cloud computing environments in an efficient manner....

There has been a great deal of recent research interest regarding the storage and utilization of big data via remote cloud platforms. The efficiency of large data transfers from remote cloud platforms is a critical issue, and dedicated networks are used for data transfer. To resolve the data transfer efficiency issue, it is necessary to tune the L2...

It is well known that cloud computing has many potential advantages over traditional distributed systems. Many enterprises can build their own private cloud with open source infrastructure as a service (IaaS) frameworks. Since enterprise applications and data are migrating to private cloud, the performance of cloud computing environments is of utmo...

Legacy networks do not open the precise information of the network domain because of scalability, management and commercial reasons, and it is very hard to compute an optimal path to the destination. According to today’s ICT environment change, in order to meet the new network requirements, the concept of software-defined networking (SDN) has been...

The quality of medical treatment can be promoted by transmitting high-definition medical images and sharing these images. The high speed transmission network is a requirement for the ultra high-definition media. A high quality medical research and education can be provided by connecting resources and media-data through the superhigh speed research...

Software Defined Network (SDN) emerged to fundamentally solve high cost and complexity in construction/operation/management of existing networks. Current SDN is in the initial stage of research /development and has been studied focusing on small and medium scale networks such as data center network, campus network and enterprise network. In additio...

Virtualization is to provide virtually all types of technologies used on the physical PC. However, in a virtualization technique, services can be modified and adjusted to satisfy user requirements, the cost of hardware purchases and hardware constructions is not occurred. Beside, this virtualization supports multiple guest operating systems on a ho...

In this paper, we have interests on one application for IoT: Environmental Monitoring. Lots of smart objects deploys at some position, gathers data periodically. Several kinds of techniques should support for the application to do the job. In this paper, we focus on two among them: local storage management algorithm and periodic data gathering by m...

The recent wide expansion of applicable three-dimensional (3D) printing and software-defined networking (SDN) technologies has led to a great deal of attention being focused on efficient remote control of manufacturing processes. SDN is a renowned paradigm for network softwarization, which has helped facilitate remote manufacturing in association w...

A scheduling scheme is proposed to reduce execution time by means of both checkpoint sharing and task duplication under a peer-to-peer (P2P) architecture. In the scheme, the checkpoint executed by each peer (i.e., a resource) is used as an intermediate result and executed in other peers via its duplication and transmission. As the checkpoint is clo...

Mobile grid is a branch of grid computing that incorporates mobile devices into the grid infrastructure. It poses new challenges because mobile devices are typically resource-constrained and exhibit unique characteristics such as instability in network connections. New scheduling strategies are imperative in mobile grid to efficiently utilize the d...

As computer systems have become more complex and dynamic, unstructured and decentralized techniques serve as basic building blocks in large-scale systems such as cloud computing systems. In particular, we consider a gossip-based algorithm, one of the unstructured overlay construction techniques. In this paper, we propose a membership management mec...

This paper considers the problem of centralized spectrum allocations in wireless sensor networks towards the following goals: (1) maximizing fairness, (2) reflecting the priority among sensor data, and (3) avoiding unnecessary spectrum handoff. We cast this problem into a multiobjective mixed integer nonconvex nonlinear programming that is definite...

The Desktop Grid Systems (DGSs) have supported a resource-providing environment for large-scale applications, utilizing the idle CPU cycle of the desktop computers connected over the Internet. Moreover, a variety of large-scale applications, such as an analysis of genome sequence in biotechnology, climate prediction in meteorology, etc., has been s...

Recently, the cloud computing is a computing paradigm that constitutes an advanced computing environment that evolved from the distributed computing. And the cloud computing provides acquired computing resources in a pay-as-you-go manner. For example, Amazon EC2 offers the Infrastructure-as-a-Service (IaaS) instances in three different ways with di...

SUMMARY Desktop grids are platforms for grid computing that incorporate desktop resources into a grid infrastructure. The purpose of this computing paradigm is to process a massive computational tasks by exploiting the donated resources connected over the Internet. In desktop grids, it is important to guarantee fast turnaround time in the presence...

Traditional Byzantine consensus in distributed systems requires n ≥ 3f + 1, where n is the number of nodes. In this paper, we present a scalable and leaderless Byzantine consensus implementation based on gossip, requiring only n ≥ 2f + 1 nodes. Unlike conventional distributed systems, the network topology of cloud computing systems is often not ful...

In this paper, we propose the low Time-To-Live (TTL)-based UDP hole punching scheme to reduce the load on the SIP registrar for Network Address Translator (NAT) traversal. For this purpose, the low TTL value is determined by executing ‘traceroute’ for the server reflexive IP address obtained through the SIP registration. In the proposed scheme, sin...

This paper considers the problem of centralized spectrum allocations in wireless cognitive radio sensor networks towards the following goals: (1) maximizing fairness reflecting the priority among sensor data, and (2) avoiding unnecessary spectrum handoff. We cast this problem into a multiobjective mixed integer non-convex nonlinear programming. To...

The cloud computing is a computing paradigm that users can rent computing resources from service providers as much as they require. A spot instance in cloud computing helps a user to utilize resources with less expensive cost, even if it is unreliable. In this paper, we propose the workflow scheduling scheme that reduces the task waiting time when...

An important research challenge about the traditional Internet environment is to enable open networking architecture on which end users are able to innovate the Internet based on the technologies of network programmability, virtualization, and federation. The SDN (Software Defined Network) technology that includes OpenFlow protocol specifications,...

Directional sensor networks composed of a large number of directional sensors equipped with a limited battery and with a limited angle of sensing have recently attracted attention. Maximizing network lifetime is a challenge in developing energy-efficient directional sensor networks, while covering all of the targets in a given area. However, the ex...

A high-quality service for applications in cloud computing environments is guaranteed by making efficient use of resources in data centers. Applications should be allocated to resources suitable for the load of data centers to achieve this. The complex and dynamic nature of the load prevents the proper selection of one of multiple data centers and...

Desktop grid computing is the computing paradigm that can execute large-scale computing jobs using the desktop resources with heterogeneity and volatility. However, such the computing environment can not guarantee the stability and reliability of task execution because the desktop resources with different performance can freely participate and leav...

In future ubiquitous networks, sensor nodes should collect various environmental data and parameters. Because sensor nodes tend to have small and often irreplaceable batteries with limited power capacity, energy-efficient aggregation and routing are essential to achieve to a prolonged network lifetime. We propose a simple cluster-based data aggrega...

Determining termination in dynamic environments is hard due to node joining and leaving. In previous studies on termination detection, some structures, such as spanning tree or computational tree, are used. In this work, we present an unstructured termination detection algorithm, which uses a gossip based scheme to cope with scalability and fault-t...

For years, computer scientists have been dreaming of innovating Internet in terms of performance, reliability, energy efficiency, security, and so on. However, it is nearly impossible to carry out practical large-scale experiments and verification, since new software and programs are hardly evaluated on the current Internet environment where router...

We propose Peer-to-Peer-based (P2P-based) home monitoring system architecture to exploit a vacuum robot with an IP camera, a movable IP camera, without requiring a number of cameras for the whole monitoring at home. The key implementation issues for the proposed home monitoring system are (1) the easy configuration of a vacuum robot to connect to W...

A key challenge in developing energy-efficient sensor networks is to extend network lifetime in resource-limited environments. As sensors are often densely distributed, they can be scheduled on alternative duty cycles to conserve energy while satisfying the system requirements. Directional sensor networks composed of a large number of directional s...

A result verification procedure is required to guarantee the correctness of task results executed by any unspecified resources in desktop grids. Voting-based and trust-based schemes have typically been used for desktop grids. However, these schemes can encounter two problems: waste of resources, due to redundant replications of each task, and incre...

The efficiency of clustering in multi-hop networks can be controversial since the clustering in multi-hop ad hoc networks can incur a significant overhead that the benefit of the clustering can be cancelled out by the overhead. We propose a simple cluster based data aggregation and routing algorithm for multi-hop wireless sensor networks and show t...

Scientific co-work needs not only cut-edge network infrastructures for large-scale networks but also network technologies for high-performance networks. Specific group network is connected several sites over multi-domains It should support dedicated network resources and advanced measurement for collaborative scientists. In this paper, we introduce...

Traditional Internet has confronted quite a few problems in terms of network security, scalability, performance, etc., mainly due to the rapid increase of the number of end-users and various new service demands. Therefore, Future Internet researches have been resolving the fundamental weakness of traditional Internet. As a part of Future Internet d...

Augmented Reality (AR), which is an emerging information technology that combines physical and virtual realities, is used in wide spectrum of domains. Due to technological advances of mobile devices, the AR application users increase and services area becomes global scale in mobile environment. As a result, the volume of data that the AR applicatio...

In this paper, we proposes the WSN (Wireless Sensor Network) algorithm which is applied sensor node that has low power consumption and efficiency measurement. Moreover, the efficiency routing protocol is proposed in this paper. The proposed algorithm reduces power consumption of sensor node data communication. It has not researched in LEACH (Low-En...

It is important that desktop grids should be able to aggressively deal with the dynamic properties that arise from the volatility and heterogeneity of resources. Therefore, it is required that task scheduling be able to positively consider the execution behavior that is characterized by an individual resource. In this paper, we implement a log anal...

As a promising tool for monitoring the physical world, directional sensor networks (DSNs) consisting of a large number of directional sensors are attracting increasing attention. As directional sensors in DSNs have limited battery power and restricted angles of sensing range, maximizing the network lifetime while monitoring all the targets in a giv...

The extensive capability of sensors let sensors autonomously collect various information on smart objects and store them to the spatial database through the wireless sensor networks. Based on spatial database, location-dependent information services (LDISs) can supply the resources according to the user locations. In LDISs, nearest-neighbour querie...

The cloud computing is a computing paradigm that users can rent computing resources from service providers as much as they require. A spot instance in cloud computing helps a user to utilize resources with less expensive cost, even if it is unreliable. When a user performs tasks with unreliable spot instances, failures inevitably lead to the delay...

In multiple datacenters-based cloud environments, virtual machines migrates across nodes located in the same or different datacenter to provide users with efficient resource provisioning services. Especially, migration between nodes located in different datacenter usually works on a wide area network. However, it takes a longer time than a local ar...

Recent advances inoptical networks lead the advent of service sensitive applications andthe community researches free from the individual research. Sensitive applications and community researches overOptical Private Network (OPN) is required to supportefficient network resource management, intelligent network switching, and sophisticated access con...

In rotatable directional sensor networks, maximizing network lifetime while covering all the targets and forwarding the sensed data to the sink is a challenge problem. In this paper, we address the Maximum Directional Cover Tree (MDCT) problem of organizing the directional sensors into a group of non-disjoint subsets to extend the network lifetime....

In this paper, we propose an efficient one-pass algorithm for shot boundary detection and a cost-effective anchor shot detection method with search space reduction, which are unified scheme in news video story parsing. First, we present the desired requirements for shot boundary detection from the perspective of news video story parsing, and propos...

With the rapid growth of the electronic-book (e-book) market, various types of e-book readers, such as dedicated e-book reading devices and e-book reader applications, have been released. However, the user interfaces of these e-book readers are highly diverse, which is becoming a major problem regarding usability. In this paper, user preferences fo...

It is important that desktop grids should be aggressively deal with the dynamic properties arisen from the volatility and heterogeneity of resources. Therefore, it is required that task scheduling should positively consider the execution behavior that is characterized by an individual resource. In this paper, we implement a log analysis system whic...

Advances in network technologies lead not only the advent of new applications but also research form change from the individual research. Research and Development communities for specific cooperative workgroups over LP (Light Path) are required to support dedicated network resources, intelligent network management, and sophisticated access control...

Directional sensor networks (DSNs) comprise a large number of sensors equipped with a limited battery and limited angles of sensing range. In DSNs, maximizing network lifetime while covering all the targets in a given area is still a challenge problem. A major technique to save the energy power of sensors is to use a node wake-up scheduling protoco...

Mobile Grid is a branch of Grid where the infrastructure includes mobile devices. The mobile Grid exhibits different challenges such as resource-constraints and users’ movements, compared to the traditional Grid. Mobile agent is an attractive technology to overcome these challenges. In this paper, we present a new mobile Grid system based on the mo...

Mobile Grid is a branch of Grid computing where the infrastructure includes mobile devices. Because mobile devices are resource-constrained, mobile Grid should provide new scheduling strategies considering its environment. This paper presents a group-based fault tolerance scheduling algorithm. The algorithm classifies mobile devices into several gr...

Grid computing using wireless networks is receiving increasing attention and is expected to become a critical part of future grid computing. However, the inherent challenges of mobile environments such as mobility management, disconnected operation, device heterogeneity, service discovery, and resource sharing are significant issues in mobile grid...

Recently, many studies have attempted to utilize mobile nodes as resources in mobile grids. Due to their underlying restrictions such as intermittent communication disconnections, limited battery capacity, and so on, mobile nodes are less reliable than wired nodes for job processing. Therefore, it is imperative to find an enhanced job scheduling me...

The recent tendency of transfer from centralized desktop to P2P desktop grids requires redesigning the result verification mechanism that has been developed for the former. Since there is no central server to verify the correctness of task results in P2P desktop grids, it is difficult to intactly apply the existing mechanisms to P2P environments. I...

Since the emergence of WSNs (Wireless Sensor Networks), various middleware architectures have been proposed to achieve a suitable abstraction from the distribution and management tasks of sensor devices. This allows users to focus on application development. In the near future, WSNs will be more pervasive, common, and distributed. Programming on WS...

Since directional sensor networks (DSNs) are composed of a large number of sensors equipped with a limited battery and limited angles of sensing range, maximizing network lifetime while covering all the targets in a given area is still a challenge problem. In this paper, we first address the MSCD (Maximum Set Cover for DSNs) problem that is known a...

Recently, the simulation techniques using computers have been actively utilized to examine the effects of social or physical interactions. Those works often generate very large amounts of data, and to deal with them, it may be necessary to use high-performance supercomputers as well as to develop efficient algorithms. This paper presents the result...

In this paper we discuss the design of result verification in desktop grid systems. In this design, correctness and performance are considered as important issues. To guarantee the correctness of work results, sabotage-tolerant mechanisms have been mainly used, such as voting-based schemes and trust-based schemes. However, these mechanisms result i...

A result verification procedure is required to guarantee the correctness of task results executed by any unspecified resource in desktop grids. Voting-based and trust-based schemes have typically been used for desktop grid. However, these schemes can encounter two problems: waste of resources, due to redundant replications of each task, and increas...

An important issue in the PC grid computing environment that is characterized by volatility and heterogeneity is the minimization of execution time for all tasks. This paper proposes a scheduling mechanism to reduce such execution time by means of both checkpoint sharing and task duplication under a peer-to-peer (P2P) architecture. In the mechanism...

The emerging Grid is extending the scope of resources to mobile devices and sensors that are connected through unreliable networks. Nowadays the number of mobile device users is increasing dramatically and the mobile devices provide various capabilities such as location awareness that are not normally incorporated in fixed Grid resources. Neverthel...

Many recent studies in the field of data transmission have considered location-based services. Prefetching and caching are exemplary techniques for data transmission, and offer advantages in user-centric services in location-dependent data environments. However, in mobile environments, prefetching and caching inevitably require frequent uplink requ...

In a peer to peer grid computing system, volunteers (i.e., resource provides) with heterogeneous properties can freely join and leave in the middle of their computation. Thus, the system should be adaptive to a dynamic changing environment. In particular, scheduling, result certification, and replication mechanisms must be dynamic and adaptive in s...

In this paper, we discuss the design of result verification systems to support deadline tasks in desktop grid systems. Both correctness and performance are considered important issues in the design of such systems. To guarantee the correctness of results, voting-based and trust-based sabotage-tolerance mechanisms are generally used. However, these...

Although desktop Grid computing has been regarded as a cost-efficient computing paradigm, the system has suffered from scalability issues caused by its centralized structure. In addition, resource volatility generates system instability and performance deterioration. However, regarding the provision of a reliable and stable execution environment, r...

In this paper, we discuss the design of replication mechanism to guarantee correctness and support deadline tasks in desktop grid systems. Both correctness and performance are considered important issues in the design of such systems. To guarantee the correctness of results, voting-based and trust-based sabotage tolerance mechanisms are generally u...

In a desktop grid computing environment, voluntary desktops (i.e., resource providers) are free to leave and join independently in the middle of execution. To develop a reliable desktop grid computing system, a scheduling scheme must consider the dynamic nature (i.e., volatility) of volunteers. Existing desktop grid computing systems, however, do n...

In mobile computing environments, a user's mobility and query patterns are multiform. To support an adequate service to the user within quick period, it is important to consider the user's various interests. As the development of the mobile device, the work of client-side has been getting more and more without continuous connection between client a...

In this paper, in order to reduce the explosive increase of the search space as the input dimension grows, we present a new represen- tation method for the structure of fuzzy rules, a graph structured fuzzy system. The graph structured fuzzy system can flexibly cope with the in- crease of the input space by selecting these fuzzy rules that signific...

To design a stable global computing environment supporting reliable job execution and covering unanticipated state changes of hosts, the dynamic characteristics (i.e. volatilities) of hosts should be considered. Since a host is not dedicated to the system, voluntary hosts are free to leave and join autonomously in the middle of execution. As curren...

A peer-to-peer grid computing is complicated by heterogeneous capabilities, failures, volatility, and lack of trust because it is based on desktop computers at the edge of the Internet. In order to improve the reliability of computation and gain better performance, a replication mechanism must adapt to these distinct features. In other words, it is...

As the Internet is widely used, high performance networks and systems prompts appearance of various applications and requests higher capacity resources. Recently, studies on grid are actively conducted to reorganize each computing resource, which used to be dispersed for each application requesting these high capacity calculation resources, into a...

Peer-to-peer grid computing is an attractive computing paradigm for high throughput applications. However, both volatility Peer-to-peer grid computing is an attractive computing paradigm for high throughput applications. However, both volatility due to the autonomy of volunteers (i.e., resource providers) and the heterogeneous properties of volunte...

In a peer to peer grid computing environment, volunteers have heterogeneous properties and dynamically join and leave during execution. Therefore, it is essential to adapt to an unstable and widely distributed environment. However, existing scheduling and result certification mechanisms do not adapt to such a dynamic environment. As a result, they...

In a peer to peer grid computing environment, volunteers are exposed to failures such as crash and link failures. In addition, since volunteers can dynamically join and leave executions and they are not dedicated only to a peer to peer grid computing, the executions of volunteers are stopped or suspended more frequently than in a grid computing env...

Recently, as the number of mobile terminals (or users) keeps explosively increasing, the location management to track the mobile terminals in mobile communication networks is becoming more important. However, previous schemes have used static location information without any consideration about the moving direction of a mobile terminal. For a fixed...

Optimistic log-based rollback recovery protocols have been regarded as an attractive fault-tolerant solution in distributed systems based on message-passing paradigm due to low overhead in failure-free time. These protocols are based on a Piecewise Deterministic (PWD) Assumption model. They, however, assumed that all logged non-deterministic events...

We introduce a new system of predicting future location of users in mobile networks, and apply the system to the failure restoration of mobility databases. The prediction system is based on a neuro-fuzzy inference system that we developed. The system is adaptable in the sense that it “learns” and “predicts” (in a sense that is formally defined) fro...

Fault tolerance is essential to the further development of desktop grid computing system in order to guarantee continuous and reliable execution of tasks in spite of failures. In a desktop grid computing environment, volunteers are often susceptible to volunteer autonomy failures such as volatility failure and interference failure in the middle of...

This paper proposes a forwarding pointer-based cache scheme (PB-Cache scheme) that can reduce the signaling cost for location management in PCS networks. In the existing cache scheme, the use of cache information can effectively reduce the signaling traffic for locating frequently called mobile users. However, when the cache information is obsolete...

This paper proposes a new location caching scheme that can reduce the signaling cost for location management in PCS networks. In the existing cache scheme, the use of cache information can effectively reduce the signaling traffic for locating frequently called mobile users. However, when the cache information is obsolete, it results in much more si...

This paper proposes a restoration scheme based on mobility learning and prediction in the presence of the failure of mobility databases in personal communication systems (PCSs). In PCSs, mobility databases must maintain the current location information of users to provide a fast connection for them. However, the malfunction of mobility databases ma...

The IETF Mobile IPv6 enables any IPv6 node to both cache the Care-of Address associated with a mobile node's home address, and to directly send packets addressed to a mobile node at the Care-of Address using the IPv6 routing header. Support for optimizing the route is built in as a fundamental part of the protocol. Several hierarchical schemes have...

Recently, hierarchical architecture for location databases has been proposed in order to accommodate the growing number of PCSs user. With the 3-level hierarchical database architecture, which is compatible with the current cellular mobile systems, newly developed additional databases, including the regional location database (RLR), are positioned...

Mobility prediction is an important issue for efficient management in mobile computing. Whenever users move to a new location, mobile systems should know about their location change so that the connection is not in terrupted. In this paper, we focus on the simulation of a user mobility prediction scheme based on neuro-fuzzy theory. Our scheme predi...

In this paper, in order to reduce the explosive increase of the search space as the input dimension grows, we present a new representation method for the structure of fuzzy rules, a graph structured fuzzy system. The graph structured fuzzy system can flexibly cope with the increase of the input space by selecting these fuzzy rules that significantl...

In this paper, we propose a new location management scheme that reduces location update and query cost. In order to reduce location update and query cost, the proposed scheme use movement locality. The scheme has the following features: (i) for mobile terminals in neighboring location areas, location update requires a one-hop message exchange, (ii)...

Managing location information of mobile terminals is an important issue in mobile computing systems. The IS-41 and the GSM schemes are inefficient in the following situations: (1) mobile terminals frequently move to neighboring registration area, (2) frequently communicate with mobile terminals that reside at neighboring registration area. In this...

In PCS (personal communication systems) networks, location management deals with the problem of tracking down a mobile user. It involves two kinds of activ- ities: one is location updating and the other is paging [1]. Each cost for location updating and paging is significantly associated with each other and therefore, has a trade-off relationship t...