Jong-Eon Lee

Policy-Based Management for Self-Managing Wireless Sensor Networks

SUMMARY In a wireless sensor network (WSN), a large number ofsensor nodes are deployed over a wide area and multi-hop communica-tions are required between the nodes. Managing numerous sensor nodesis a very complicated task, especially when the energy issue is involved.Even though a number of ad-hoc management and network structuring ap-proaches for WSNs have been proposed, a management framework cov-ering the entire network management infrastructure from the messagingprotocol to the network structuring algorithm has not yet been proposed. Inthis paper we introduce a management framework for WSNs called SNOW-MAN (SeNsOr netWork MANagement) framework. It employs the policy-based management approach for letting the sensor nodes autonomously or-ganize and manage themselves. Moreover, a new light-weight policy dis-tribution protocol called TinyCOPS-PR and policy information base (PIB)are also developed. To facilitate scalable and localized management ofsensor networks, the proposed SNOWMAN constructs a 3-tier hierarchyof regions, clusters, and sensor nodes. The effectiveness of the proposedframework is validated through actual implementation and simulation us-ing ns-2. The simulation results reveal that the proposed framework allowssmaller energy consumption for network management and longer networklifetime than the existing schemes such as LEACH and LEACH-C for prac-tical size networks.

Hierarchical Node Clustering Approach for Energy Savings in WSNs

This paper proposes an energy efficient clustering algorithm for self-organizing and self-managing WSNs, called SNOW cluster. It introduces region node selection as well as cluster head election based on the residual battery capacity of nodes to reduce the costs of managing sensor nodes and of the communication among them. SNOW cluster clusters periodically to select cluster heads that are richer in residual energy level, compared to the other nodes to achieve load balancing and extend the lifetime of every individual sensor nodes. After the cluster heads are selected, SNOW cluster selects the region nodes in the cluster heads based on the energy level of them and chooses gateway nodes between clusters based on their location information. The effectiveness of the proposed SNOW cluster algorithm is validated through actual implementation and simulation using ns-2. The simulation results reveal that the proposed framework allows smaller energy consumption for network management and longer network lifetime than the existing schemes such as LEACH and LEACH-C for practical size networks.

Clustering based Routing Algorithm for Efficient Emergency Messages Transmission in VANET

Abstract Vehicle Ad hoc Network (VANET) is next-generation network technology to provide various services using V2V (Vehicle-to-Vehicle) and V2I (Vehicle-to-Infrastructure). In VANET, many researchers proposed various studies for the safety of drivers. In particular, using the emergency message to increase the efficiency of traffic safety have been actively studied. In order to efficiently transmit to moving vehicle, to send a quick message to as many nodes is very important via broadcasting belong to communication range of vehicle nodes. However, existing studies have suggested a message for transmission to the communication node through indiscriminate broadcasting and broadcast storm problems, thereby decreasing the overall performance has caused the problem. In addition, theses problems has decreasing performance of overall network in various form of road and high density of vehicle node as urban area. Therefore, this paper proposed Clustering based Routing Algorithm (CBRA) to efficiently transmit emergency message in high density of vehicle as urban area. The CBRA managed moving vehicle via clustering when vehicle transmit emergency messages. In addition, we resolve linkage problem between vehicles according to various form of road. The CBRA resolve link brokage problem according to various form of road as urban using clustering. In addition, we resolve broadcasting storm problem and improving efficacy using selection flooding method. simulation results using ns-2 revealed that the proposed CBRA performs much better than the existing routing protocols.

Policy-based differentiated QoS provisioning for DiffServ enabled IP networks

This paper proposes and implements a policy-based QoS management platform for DiffServ enabled IP networks, which specifies QoS policies to guarantee QoS requirements. The proposed platform integrates the function of policy-based management and QoS monitoring by extending the original IETF policy-based management architecture. High-level QoS policies are represented as valid XML documents and are translated to EJB beans in the EJB-based policy server of the platform. The policy distribution and the QoS monitoring are processed using SNMP. This paper also describes the implementation of Linux-based DiffServ routers with DiffServ MIB and analyzes the experimental results using a video streaming system.

Autonomous management of large-scale ubiquitous sensor networks

A framework for the autonomous management of large-scale ubiquitous sensor networks called SNOWMAN (SeNsOr netWork MANagement) is proposed in this paper. In large-scale ubiquitous sensor networks, a huge number of sensor nodes are deployed over a wide area and long distances and multi-hop communication is required between nodes. So managing numerous ubiquitous sensor nodes directly is very complex and is not efficient. The management of large-scale ubiquitous sensor networks therefore must be autonomic with a minimum of human interference, and robust to changes in network states. The SNOWMAN is responsible for monitoring and controlling ubiquitous sensor networks based on policy-based management paradigm. It allows administrators to simplify and automate the management of ubiquitous sensor networks. It can also reduce the costs of managing sensor nodes and of the communication among them using a new hierarchical clustering algorithm.

Implementing an JAIN based SIP system for supporting advanced mobility

Mobile IP(MIP) and SIP have been proposed to support mobility in the wireless internet working at different layers of the protocol stack. However MIP has some problems such as triangle routing, the need of each hosts home address, the overhead of tunneling and the lack of wide deployment. Thus we proposed a scheme for supporting mobility based on SIP in this research. A novel SIP system to provide a hierarchical registration has been designed according to this scheme. Our SIP system has been established by implementing JAIN technologies which follow next generation network standards to support the mobility of wireless terminal. This system successfully satisfied ITU-T recommandation.