• Journal of Digital Convergence
• /
• v.10 no.9
• /
• pp.289-295
• /
• 2012

Routing technique of wireless sensor network that is presented to improve effectiveness of consumption in energy at the previous study is existing in various ways, however for routing, its own location data and nodes' location data close to with 1-hop distance should be kept. And it uses multi-hop transmission method that transmits data to BS node via several nodes. This technique makes electronic consumption of sensor node and entire network's energy consumption so that it makes effective energy management problem. Therefore, this paper suggests location based 1-hop routing technique of BS node that satisfies distance $d{\pm}{\alpha}$ with source node using RSSI and radio wave range of sensor node.

• Convergence Security Journal
• /
• v.7 no.2
• /
• pp.107-118
• /
• 2007

Distributed wireless sensor network in various environment have characteristic that is surveillance of environment-element and offering usefully military information but there is shortcoming that have some secure risks. Therefore secure service must be required for this sensor network safety. More safe and effective techniques of node administration are required for safe communication between each node. This paper proposes effective cluster-header and clustering techniques in suitable administration techniques of group-key on sensor network. In this paper, first each node transmit residual electric power and authentication message to BS (Base-Station). BS reflects "Validity Authentication Rate" and residual electric power. And it selects node that is more than these regularity values by cluster header. After BS broadcasts information about cluster header in safety and it transmits making a list of information about cluster member node to cluster header. Also, Every rounds it reflects and accumulates "Validity Authentication Rate" of former round. Finally, BS can select more secure cluster header.

• Journal of Communications and Networks
• /
• v.17 no.3
• /
• pp.247-255
• /
• 2015

In this paper, we propose an adaptive time division multiple access based medium access control (MAC) protocol, called bitmap-assisted shortest job first based MAC (BS-MAC), for hierarchical wireless sensor networks (WSNs). The main contribution of BS-MAC is that: (a) It uses small size time slots. (b) The number of those time slots is more than the number of member nodes. (c) Shortest job first (SJF) algorithm to schedule time slots. (d) Short node address (1 byte) to identify members nodes. First two contributions of BS-MAC handle adaptive traffic loads of all members in an efficient manner. The SJF algorithm reduces node's job completion time and to minimize the average packet delay of nodes. The short node address reduces the control overhead and makes the proposed scheme an energy efficient. The simulation results verify that the proposed BS-MAC transmits more data with less delay and energy consumption compared to the existing MAC protocols.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2010.11a
• /
• pp.913-916
• /
• 2010

Wireless sensor networks consist of small battery powered devices with limited energy resources. Once deployed, the small sensor nodes are usually inaccessible to the user, and thus replacement of the energy source is not feasible. Hence, energy efficiency is a key design issue that needs to be enhanced in order to improve the life span of the network. In BCDCP, all sensors send data from CH (Cluster Head) and then to BS (Base Station). BCDCP works well in small-scale network but in large scale network it is not appropriated since it uses much energy for long distance wireless communication. We propose a routing protocol - Triangular Clustering Routing Protocol (TCRP) - to prolong network life time through the balanced energy consumption. TCRP selects cluster head of triangular shape. The sensor field is divided into energy level and in every level we choose one node as a gate node. This gate node collects data and sends it to the leader node. Finally the leader node sends the aggregated data to the BS. We show TCRP outperforms BCDCP with several experiments.

• Journal of Korea Multimedia Society
• /
• v.12 no.9
• /
• pp.1273-1287
• /
• 2009

PEGASIS, a chain-based protocol, forms chains from sensor nodes so that each node transmits and receives from a neighbor. In this way, only one node (known as a HEAD) is selected from that chain to transmit to the sink. Although PEGASIS is able to balance the workload among all of the nodes by selecting the HEAD node in turn, a considerable amount of energy may be wasted when nodes which are far away from sink node act as the HEAD. In this study, DERP (Distance-based Energy-efficient Routing Protocol) is proposed to address this problem. DERP is a chain-based protocol that improves the greedy-algorithm in PEGASIS by taking into account the distance from the HEAD to the sink node. The main idea of DERP is to adopt a pre-HEAD (P-HD) to distribute the energy load evenly among sensor nodes. In addition, to scale DERP to a large network, it can be extended to a multi-hop clustering protocol by selecting a "relay node" according to the distance between the P-HD and SINK. Analysis and simulation studies of DERP show that it consumes up to 80% less energy, and has less of a transmission delay compared to PEGASIS.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37 no.3B
• /
• pp.149-157
• /
• 2012

In WSN environment, the sensor nodes collect sensed data, and transmit data to the BS. BS is difficult to trust the data from unauthenticated nodes. Therefore, many papers have been proposed about the node authentication and the safety of data. In the AM-E paper, data is delivered after node authentication. In this time, the sensor nodes are directly communicated to BS the AREQ/AREP message for authentication. Therefore, the sensor nodes consume more energy for authentication. Also, noes communicate directly with the BS for authentication will have problem due to the limited energy of nodes. In this paper, the same security with AM-E is supported, Furthermore, to minimize the energy consumption, IDE based hierarchical node authentication protocol is proposed. Compared with AM-E, the number of alive nodes is increased about 39%. Thus, the entire network life time is extended and energy efficiency is improved.

• Journal of the Korea Society of Computer and Information
• /
• v.13 no.2
• /
• pp.177-183
• /
• 2008

In this paper we suggest a hybrid MAC protocol for wireless sensor networks (WSN) to enhance network performance. The proposed MAC scheme is specifically designed for wireless sensor networks which consist of lots nodes. The contributions of this paper are: First, the proposed scheduling algorithm is independent of network topology. Even though the BS node has lots of one hop node in dense mode network, all the time slots can be assigned fully without increasing frequencies. Second, BS one hop nodes can use more than one time slots if necessary, so total network performance is increased. We compare the network performance of the proposed scheme with previous one, HyMAC [1].

• The KIPS Transactions:PartC
• /
• v.16C no.6
• /
• pp.783-790
• /
• 2009

The necessity of wireless sensor networks is increasing in the recent years. So many researches are studied in wireless sensor networks. The clustering algorithm provides an effective way to prolong the lifetime of the wireless sensor networks. The one-hop routing of LEACH algorithm is an inefficient way in the energy consumption of cluster-head, because it transmits a data to the BS(Base Station) with one-hop. On the other hand, other clustering algorithms transmit data to the BS with multi-hop, because the multi-hop transmission is an effective way. But the multi-hop routing of other clustering algorithms which transmits data to BS with multi-hop have a data bottleneck state problem. The unequal clustering algorithm solved a data bottleneck state problem by increasing the routing path. Most of the unequal clustering algorithms partition the nodes into clusters of unequal size, and clusters closer to the BS have small-size the those farther away from the BS. However, the energy consumption of cluster-head in unequal clustering algorithm is more increased than other clustering algorithms. In the thesis, I propose an energy efficient unequal clustering algorithm which decreases the energy consumption of cluster-head and solves the data bottleneck state problem. The basic idea is divided a three part. First of all I provide that the election of appropriate cluster-head. Next, I offer that the decision of cluster-size which consider the distance from the BS, the energy state of node and the number of neighborhood node. Finally, I provide that the election of assistant node which the transmit function substituted for cluster-head. As a result, the energy consumption of cluster-head is minimized, and the energy consumption of total network is minimized.

• Journal of Digital Convergence
• /
• v.12 no.1
• /
• pp.339-345
• /
• 2014

This study has a purpose that improves efficiency of energy management and adaptation followed by movement of node better than the various early studied routing techniques. The purpose of this paper is the technique that uses RSSI value and location of sensor that is received by each sensor node to routing. This sduty does not save node information of 1-hop distance. And it solves energy-inefficient traffic problem that happens during data exchange process for middle node selection in close range multi hop transmission technique. The routing protocol technique that is proposed in this study selects a node relevant to the range of transmission which is set for RSSI value that is received by each node and selects the closest node as a middle node followed by location data. Therefore, it is for not exhaustion of node's energy by managing energy efficiently and cutting data transmission consuming until the destination node.

• Korean Management Science Review
• /
• v.27 no.3
• /
• pp.1-14
• /
• 2010

In this paper we study the access network design problem in Universal Mobile Telecommunication Systems (UMTS) networks. Given the location of radio base stations (node-Bs), their traffic demands, and the candidate facility centers for locating radio network controllers (RNCs), the problem is to determine the configuration of access network, including the number and location of facility centers, the number of RNCs in each facility center, and the links between RNCs and node-Bs, with the objective being to design such a network at the minimum cost. We provide a mathematical formulation of the problem with constraints on RNC and node-B capacities, along with a lower bounding method. We develop a heuristic algorithm with two different initial solution methods designed to strengthen the solution quality. The computational efficacy of their procedures is then demonstrated on a number of test problems.