Yong-Hyuk Moon

Multihybrid job scheduling for fault-tolerant distributed computing in policy-constrained resource networks

Unpredictable fluctuations in resource availability often lead to rescheduling decisions that sacrifice a success rate of job completion in batch job scheduling. To overcome this limitation, we consider the problem of assigning a set of sequential batch jobs with demands to a set of resources with constraints such as heterogeneous rescheduling policies and capabilities. The ultimate goal is to find an optimal allocation such that performance benefits in terms of makespan and utilization are maximized according to the principle of Pareto optimality, while maintaining the job failure rate close to an acceptably low bound. To this end, we formulate a multihybrid policy decision problem (MPDP) on the primary-backup fault tolerance model and theoretically show its NP-completeness. The main contribution is to prove that our multihybrid job scheduling (MJS) scheme confidently guarantees the fault-tolerant performance by adaptively combining jobs and resources with different rescheduling policies in MPDP. Furthermore, we demonstrate that the proposed MJS scheme outperforms the five rescheduling heuristics in solution quality, searching adaptability and time efficiency by conducting a set of extensive simulations under various scheduling conditions.

Design of P2P grid networking architecture using k -redundancy scheme based group peer concept

Currently, there are many system requirements to guarantee the scalability, fault-tolerance, and high performance in the rapidly evolving research fields such as Grid and P2P technologies. Due to the dynamic nature of the Grid computing and P2P in networks, the behavior of system might be very unpredictable in respect of reliability. In this paper, we propose the Group Peer based P2P Grid system architecture with k-Redundancy Scheme that can satisfy these requirements. With respect to load balancing, this P2P Grid system clearly shows that redundancy scheme of group peer guarantees the reliability for resource or service discovery. Through the theoretical analysis and simulation, we discuss the performance of the proposed scheme.

QRP03-5: SLA-Constrained Resource Scheduling Policy for Group Peering in P2P Grid

Due to the dynamic nature of the grid computing and P2P in networks, the behavior of system might be very unpredictable in respect of reliability. Thus, we need well-organized system architecture to provide high system availability with resource scheduling scheme for P2P grid application. In this paper, we propose the SLA-constrained resource scheduling policy methodology in order to enhance system performance in P2P grid. The simulation results show that SCPA-based job scheduling can support the load balancing and guarantee the high system availability in system performance.

An integrated approach towards aggressive state-tracking migration for maximizing performance benefit in distributed computing

This paper presents a new state-tracking migration scheme that is integrated with aggressive reservation strategies such as immediate restart, greedy backfilling and selective preemption. The main contribution of this paper is an analysis of the effects of three techniques that can be used beyond the conventional migration schemes. Our simulation results suggest that state-tracking migration with selective preemption entirely outperforms the others. We also observe that the overall performance of immediate restart strategy combining to migration can be stably maintained under various job lifetime distributions. Moreover, it is found that performance would be improved by fitting jobs ruled by the immediate restart strategy rather than queued jobs into the void-intervals under the state-tracking migration scheme.

A Cooperation Network Model for Secure Management in Dynamic P2P Flow

This paper discusses how to identify Peer-to-Peer (P2P) traffic using a blind technique without observing individual payload in the proposed cooperation network model. Traditionally, the payload inspection based traffic identification methodologies have been studied and developed for static internet traffic generated by well-known network applications such as http, ftp, telnet, smtp, etc. However, this approach is inadequate any more to detect and control newly emerging applications using P2P-like or P2P-based communication protocol. Also it strongly depends on the central intrusion detection system or firewall because signature as the prior-knowledge is normally built on that kind of systems. That fact derives three issues: performance overhead, central point of failure, and abnormality handling of traffic. Therefore, we propose the distributed detector strategy using tight cooperation between flow agent and secure gateway for indentifying the dynamic P2P traffic, even encrypted.

Cooperative remote attestation for IoT swarms

Prior remote attestation may not be suitable to scale to the proliferation of IoT device swarms. To this end, we propose a cooperative remote attestation scheme, which validates the security state and verifies the system integrity with the cooperation of neighbor devices. The efficiency of the proposed mechanism is analyzed as a cryptographic protocol and then discussed in terms of security and scalability.

A Functional Relationship Based Attestation Scheme for Detecting Compromised Nodes in Large IoT Networks

Despite memory traverse is commonly used for attestation, this approach could not feasibly work for an IoT network that requires scalable and sustainable operations. To overcome this limitation, we propose a functional relationship based attestation scheme, which verifies the integrity of battery-powered devices by analyzing the consistency among neighbors, where a consistent edge between two nodes is given if outputs of the same functions at both nodes are equal to each other. Efficiency of the proposed method is demonstrated in terms of attestation termination and detection speed.

Protecting IPTV Service Network against Malicious Rendezvous Point

In this paper, we present security mechanism to protect IPTV service network from malicious Rendezvous Point. The IPTV service network considered in this paper is overlay network that is constructed in application layer. The overlay-based IPTV service network has several advantages such as cost-effectiveness, dynamicity and scalability. However, there are several security threats against overlay network such as malicious rendezvous point attack, routing interference attack, DoS(Denial of Service) attack and so on. In this paper we analyze the security threats of overlay-based IPTV service network, and we present the brief security guidelines against it. And we present detailed security mechanisms to protect IPTV service network from malicious Rendezvous Point. For this, we design the security mechanism to guarantee trust of rendezvous point and distribute security keys such as self-generated public key of each node and group key of rendezvous point safely manner. This approach is very simple, lightweight and implementation friendly.

A Cost-Optimized Redundancy Scheme of Group Peer in P2P Grid

Several aspects of todays grids are still based on centralized or hierarchical services. However, as grid sizes increase from tens to thousands of hosts, fault tolerance is becoming a key issue. In this paper, we propose a cost-optimized reliability using redundancy scheme in redundant group peers based P2P grid. Proposed finding optimum redundancy minimizes system cost and guarantees reliability which satisfies requirements of application under the dynamic behaviors in P2P grid environments

Network resilience estimation to cascading failures

Failures of a small fraction of nodes can lead to breakdown of entire network due to overload or congestion. To understand this crucial feature in networks, we propose a load-dependent cascading failure model according to sandpile principle in this paper. Our model is effective in evaluating the overall aspect of resilience capacity in terms of connectivity efficiency against the spreading of large collapse.