• Proceedings of the KIEE Conference
• /
• 2004.11c
• /
• pp.209-211
• /
• 2004

We can categorize mobility two main fields in IP environment. If Mobile IP manages macro mobility, Cellular IP deal with micro mobility. For seamless connection, it is major problem to reduce packet loss in the network layer during handoff. This paper will introduce a scheme which reduces packet loss during micro mobility which use indirect handoff mechanism in Cellular IP, and will verify the efficiency of that scheme by computer simulation.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.12 no.10
• /
• pp.4754-4773
• /
• 2018

In sensor medium access control (SMAC) protocol, sensor nodes can only access the channel in the scheduling and listening period. However, this fixed working method may generate data latency and high conflict. To solve those problems, scheduling duty in the original SMAC protocol is divided into multiple small scheduling duties (micro duty MD). By applying different micro-dispersed contention channel, sensor nodes can reduce the collision probability of the data and thereby save energy. Based on the given micro-duty, this paper presents an adaptive duty cycle (DC) and back-off algorithm, aiming at detecting the fixed duty cycle in SMAC protocol. According to the given buffer queue length, sensor nodes dynamically change the duty cycle. In the context of low duty cycle and low flow, fair binary exponential back-off (F-BEB) algorithm is applied to reduce data latency. In the context of high duty cycle and high flow, capture avoidance binary exponential back-off (CA-BEB) algorithm is used to further reduce the conflict probability for saving energy consumption. Based on the above two contexts, we propose an improved SMAC protocol, micro duty adaptive SMAC protocol (MDA-SMAC). Comparing the performance between MDA-SMAC protocol and SMAC protocol on the NS-2 simulation platform, the results show that, MDA-SMAC protocol performs better in terms of energy consumption, latency and effective throughput than SMAC protocol, especially in the condition of more crowded network traffic and more sensor nodes.

• Journal of Electrical Engineering and Technology
• /
• v.6 no.5
• /
• pp.605-612
• /
• 2011

As the power grids are integrated into one big umbrella called a "smart grid," communication protocol plays a key role in successful operations. The successful deployment of smart grid interoperability is a major hurdle that must be overcome. The micro grid, a small power system that distributes energy resource, is operated in diverse regions. Different vendors use different communication protocols in the operation of the micro grid. Recently, the IEC 61850 has been legislated to solve the interoperability problems in power utility automation. The present paper presents a micro grid system based on the IEC 61850 protocol. It consists of a micro grid monitoring system, a protocol converter that transforms serial data to IEC 61850 data, and distributed energy resource controllers for diverse DER nodes. A developed communication gateway can be deployed for DER controllers with serial links to exchange data with IEC 61850-based devices. The gateway can be extended to IEC 61850-based distribution automation systems, substation automation systems, or SCADA.

• The KIPS Transactions:PartC
• /
• v.15C no.1
• /
• pp.51-60
• /
• 2008

Micro-mobility protocols have been developed to reduce the control message overhead due to movements of mobile nodes. With the spread of mobile devices, services using mobile nodes are increasing and multicast services are becoming more important in providing multimedia services. In this paper we propose a new multicast protocol suitable for micro-mobility environments. The proposed protocol is designed to maintain optimal multicast routing paths and continue to provide multicast services without disruption in spite of frequent handoffs due to movements of mobile nodes. We used simulation to evaluate the proposed protocol, compared its performance with existing multicast protocols for mobile environments including bi-directional tunneling, remote subscription, and MMA, and observed that the proposed protocol exhibited better performance in terms of transmission success ratio and overhead on the network.

• Proceedings of the KIEE Conference
• /
• 1999.11c
• /
• pp.649-651
• /
• 1999

This paper presents SNMP remote management system for power plants using micro-controller. Control board supporting LAN-based remote monitor and control is produced and MMI program on PC is also constructed. To expand into Internet, SNMP(Simple Network Management Protocol), the standard network management protocol of TCP/IP protocol suite, is ported to this control board consisted of micro-controller, 80c196KC, and LAN controller, Am7990DC. To overcome the constraints of CPU performance and memory capacity, TCP/P protocol suite is simplified and informations needed to management were implemented in accordance with MIB(Management Information Base) specified in RFC. Also monitoring software is constructed by Visual Basic.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.1B
• /
• pp.64-70
• /
• 2003

In order to provide seamless wireless Internet service, the basic mobile IP protocol should be enhanced to solve packet loss problem from large registration latency because frequent handoffs occur in cellular networks. In this paper, we suggest a new micro-mobility management protocol based on MPLS while supporting Qos, and evaluate its performance using simulation. We use MPLS label switching techniuqe in cellular access networks to simplify location management and speed up packet transmission. We adopt context transfer procedure to minimize the delay needed to attain prior level of service after handoff Packet loss can be minimized during handoff by transmitting received packets from old BSLER to new BSLER using a spliced LSP between them. Simulation results show that the proposed MPLS-based micro-mobility management protocol provides a seamless handoff and supports QoS of user traffic.

• The KIPS Transactions:PartC
• /
• v.11C no.7 s.96
• /
• pp.937-950
• /
• 2004

In this paper, we present the design and implementation of new execution environment named Customizable Architecture for Flexible Execution Environment(CAFEs) that supports the mechanism of protocol customization and service referencing. We introduce a new concept as micro protocols and active services to enhance software reusability. Micro protocol represents a specific algorithm or functionality of existing network protocol and the active service is in charge of binding legacy application and releasing the active network oriented services. The pro-posed active network execution environment is made up of three parts, virtual network system, protocol and service manager, event engine. First, the virtual network system is used to connect each active nodes using virtual network channels which are based on multiple existing protocol layers. Second, the protocol and service manager is responsible for composing micro protocols and active services to develop new network proto-col and service easily. Finally, the event engine is used to detect the automatic transition of system components using event delegation model. To verify the CAFTs, we have an experiment about the delivery of web contents which are suitable for the user's terminals in the wireless Internet environment. As a result. we are able to obtain the availability of developed execution environment.

• Journal of Biomedical Engineering Research
• /
• v.31 no.3
• /
• pp.234-239
• /
• 2010

We have developed and reported several micro-spikes for minimally invasive biopsy. This paper presents a diagnosis protocol for micro-spike biopsy using paraffin-based tissue collecting tool. Using the proposed tissue collecting tool, which has a negative micro-spike structure in a porous chamber, the biopsied tissue in a micro-spike is effectively detached. The proposed diagnosis protocol prevents the loss of tissues in a paraffin embedding and sectioning process. Hence, it is compatible with conventional histopathology without additional reagents and processes. The gastro-intestinal tissue of a pig is biopsied in an in vivo environment, and then it is detached from a micro-spike using the paraffin-based tissue collecting tool. A histopathological photomicrograph of the detached tissue is acquired with the proposed diagnosis protocol. The acquired image offers clinical quality. This result shows that the paraffin-based tissue collecting tool is applicable to the medical practice.

• Journal of the Korea Society of Computer and Information
• /
• v.10 no.5 s.37
• /
• pp.227-236
• /
• 2005

Hierarchical Prefix Delegation (HPD) protocol refers to a type of solution to problems inherent in non-optimal routing which occurs with Network Mobility (NEMO) basic solution. However, because HPD cannot improve the micro-mobility Problems, Problem surfaces each time Mobile Network Node (MNN) changes the attachment point; as happens also in a Mobile IPv6 (MIPv6) protocol in sen야ng Binding Update (BU) messages to Home Agent (HA) / Correspondent Nodes(CNs) By applying Hierarchical Mobile IPv6 protocol concept to HPD, this study Proposes an algorithm for effectively handling micro-mobility problems which occur with HPD in a nested NEMO environment. By sending BU only to nearby Mobility Anchor Point(MAP) during MNN location change within a MAP's domain, the proposed protocol will alleviate service disruption delays and signaling loads during the handover process, overcoming the limitations of HPD.

• Journal of the Korea Society of Computer and Information
• /
• v.11 no.1 s.39
• /
• pp.147-155
• /
• 2006

Hierarchical Prefix Delegation (HPD) protocol refers to a type of solution to problems inherent in non-optimal routing which occurs with Network Mobility (NEMO) basic solution. However, because HPD cannot improve the micro-mobility problems, problem surfaces each time Mobile Network Node (MNN) changes the attachment point; as happens also in a Mobile IPv6 (MIPv6) protocol in sending Binding Update (BU) messages to Home Agent (HA) / Correspondent Nodes(CNs). By applying Hierarchical Mobile IPv6 protocol concept to HPD, this study proposes an algorithm for effectively handling micro-mobility problems which occur with HPD in a nested NEMO environment. By sending BU only to nearby Mobility Anchor Point(MAP) during MNN location change within a MAP's domain, the proposed protocol will alleviate service disruption delays and signaling loads during the handover process, overcoming the limitations of HPD.