Eung Jun Cho

A 6LoWPAN Sensor Node Mobility Scheme Based on Proxy Mobile IPv6

In this paper, we focus on a scheme that supports mobility for IPv6 over Low power Wireless Personal Area Network (6LoWPAN) sensor nodes. We define a protocol for 6LoWPAN mobile sensor node, named 6LoMSN, based on Proxy Mobile IPv6 (PMIPv6). The conventional PMIPv6 standard supports only single-hop networks and cannot be applied to multihop-based 6LoWPAN. It does not support the mobility of 6LoMSNs and 6LoWPAN gateways, named 6LoGW, cannot detect the PAN attachment of the 6LoMSN. Therefore, we define the movement notification of a 6LoMSN in order to support its mobility in multihop-based 6LoWPAN environments. The attachment of 6LoMSNs reduces signaling costs over the wireless link by using router solicitation (RS) and router advertisement (RA) messages. Performance results show that our proposed scheme can minimize the total signaling costs and handoff latency. Additionally, we present the design and implementation of the 6LoMSN mobility based on PMIPv6 for a healthcare system. According to the experimental results, the 6LoMSN of the proposed PMIPv6-based 6LoWPAN can be expected to use more of the battery lifetime. We also verify that the 6LoMSN can maintain connectivity, even though it has the freedom of being able to move between PANs without a mobility protocol stack.

A QoS and profit aware cloud confederation model for IaaS service providers

Cloud confederation is the union of cloud data centers that allows outsourcing user requests by a cloud provider during peak hours to liberate it from the constraint of limited physical resources. Federation extends some of the features of cloud like low cost, scalability, robustness and availability while increases the price and revenue of the providers along with maintaining a high QoS by effectively utilizing the resources of the data centers. Existing works on cloud federation do not consider all three categories of instances and hence cannot maximize their profits. Moreover, the process of establishing cloud federation and taking cost efficient decisions based on QoS parameters has not yet been provided in recent works. In this paper, we have designed a data communication model for the members of a cloud confederation, which exploits clear understanding of the usage pattern, types of requests in addition to infrastructure expenses. We develop an algorithm and a model for cost calculation, which enhances the decision making process over all the VM types (on-demand, reserved, spot) to increase resources utilization and profit. The simulation results, conducted on CloudSim, indicate that, our proposed model and algorithm enhances the profit, utilization, and QoS in a cloud confederation environment compared to a number of state-of-the-art approaches.

An Adaptable Destination-Based Dissemination Algorithm Using a Publish/Subscribe Model in Vehicular Networks

Vehicular Ad Hoc Networks (VANETs) are highly dynamic and unstable due to the heterogeneous nature of the communications, intermittent links, high mobility and constant changes in network topology. Currently, some of the most important challenges of VANETs are the scalability problem, congestion, unnecessary duplication of data, low delivery rate, communication delay and temporary fragmentation. Many recent studies have focused on a hybrid mechanism to disseminate information implementing the store and forward technique in sparse vehicular networks, as well as clustering techniques to avoid the scalability problem in dense vehicular networks. However, the selection of intermediate nodes in the store and forward technique, the stability of the clusters and the unnecessary duplication of data remain as central challenges. Therefore, we propose an adaptable destination-based dissemination algorithm (DBDA) using the publish/subscribe model. DBDA considers the destination of the vehicles as an important parameter to form the clusters and select the intermediate nodes, contrary to other proposed solutions. Additionally, DBDA implements a publish/subscribe model. This model provides a context-aware service to select the intermediate nodes according to the importance of the message, destination, current location and speed of the vehicles; as a result, it avoids delay, congestion, unnecessary duplications and low delivery rate.

A Partially Distributed Intrusion Detection System for Wireless Sensor Networks

The increasing use of wireless sensor networks, which normally comprise several very small sensor nodes, makes their security an increasingly important issue. They can be practically and efficiently secured using intrusion detection systems. Conventional security mechanisms are not usually applicable due to the sensor nodes having limitations of computational power, memory capacity, and battery power. Therefore, specific security systems should be designed to function under constraints of energy or memory. A partially distributed intrusion detection system with low memory and power demands is proposed here. It employs a Bloom filter, which allows reduced signature code size. Multiple Bloom filters can be combined to reduce the signature code for each Bloom filter array. The mechanism could then cope with potential denial of service attacks, unlike many previous detection systems with Bloom filters. The mechanism was evaluated and validated through analysis and simulation.

Attack model and detection scheme for Botnet on 6LoWPAN

Recently, Botnet has been used to launch spam-mail, key-logging, and DDoS attacks. Botnet is a network of bots which are controlled by attacker. A lot of detection mechanisms have been proposed to detect Botnet on wired network. However, in IP based sensor network environment, there is no detection mechanism for Botnet attacks. In this paper, we analyze the threat of Botnet on 6LoWPAN and propose a mechanism to detect Botnet on 6LoWPAN.

A load balancing algorithm with QoS support over heterogeneous wireless networks

Coexistence of different wireless networks is a common phenomenon in todays smart communication infrastructure. Now, the big issue is to explore benefits from the heterogeneous nature of communication technology. Load balancing among the heterogeneous wireless networks is the primary goal of this paper. Load balancing without considering Quality of Service (QoS) merely inadequate in convergence of resource utilization and grade of service. So, this paper proposed a load balancing algorithm with QoS provisioning. This paper is based on a semi-distributed load balancing architecture. Firstly, IP-flow dividing ratio based soft load balancing approach is discussed for high speed features of next generation wireless networks. Secondly, an admission control function of QoS requirements is developed. Thirdly, a joint optimization function is derived and a load balancing algorithm is proposed by using the cost function. Finally, simulation results are presented for performance appraisal.

Distributed IDS for efficient resource management in wireless sensor network

Intrusion detection system (IDS) is one of the basic components of network security. IDS can use signatures or abnormal behaviors to detect attacks. When IDS uses signatures, in order to detect more attacks, we have to implement more attack signatures on IDS. However, in resource-constrained wireless sensor networks, it is not efficient to implement all of attack signatures. And it is hard to maintain attack signature database because it should be updated frequently when new kind of attacks appear. In this paper, we propose a distributed IDS mechanism which reduces the usage of memory and overhead. Analysis of our proposal shows that our proposal requires less memory.

Design and Implementation of NEMO Based ZigBee Mobile Router for Healthcare System

In this paper, we focused on the scheme which supports mobility for ZigBee sensor nodes. We adopt NEMO protocol to provide mobility for low power ZigBee sensor nodes. Therefore, we propose NEMO based ZigBee Mobile Router architecture and operations to support the network mobility of ZigBee network. Also, we present the design and implementation of the ZigBee Mobile Router for healthcare system. The architecture is particularly useful to manage patient’s mobility where each patient is equipped with ZigBee sensor nodes.

Configuration of WSN using application-aware virtual networks

In this paper, we propose protocols and mechanism for creation and working of Virtual Sensor Networks (VSN). Through simulations we support the concept and show that the proposal can achieve better results than ordinary WSN. We provide an application scenario for configuration management of WSN using the WSN concept.