IP 이동성 지원 프로토콜에 대한 비교 연구: Fast Handover 대 Mobile IPv6

백상헌,최양희 한국통신학회 2004 韓國通信學會論文誌 Vol.29 No.6A

Fast Handover[1] 프로토콜은 핸드오프 과정에서 발생하는 지연 시간을 줄임으로써 끊김없는 핸드오프가 가능하도록 해준다. 핸드오프 지연시간을 줄이기 위해서 Fast Handover는 링크 계층의 트리거 정보를 이용한 예측 기법을 사용한다. 따라서 기존 Mobile IPv6에 비해서 더 많은 시그널링 비용을 초래한다. 뿐만 아니라 가변적인 특성을 가지는 링크 특성으로 인해 예측한 정보가 정확하지 않을 수도 있고 이 경우에는 불필요한 버퍼 공간을 낭비하게 된다. 따라서, 이러한 부가적인 비용을 고려하여 Fast Handover와 Mobile IPv6의 성능을 비교, 평가하는 것이 필요하다. 본 논문에서는 두 프로토콜에서의 시그널링 비용과 패킷 전송 비용을 모델링하여 링크 계층 트리거의 시점이 전체 비용에 미치는 영향과 핸드오프 과정에서의 버퍼 요구량을 비교하였다. 그 결과 최적화된 핸드오프 성능을 위해서 트리거 시점을 적합하게 설정하는 것이 중요하다는 것을 알 수 있었다. The Fast Handover protocol [1] provides seameless handover in wireless If networks by minimizing handover latency, which uses anticipation based on layer 2 (L2) trigger information. Therefore, it incurs higher signaling costs compared with the basic Mobile U protocol. Furthermore, since the L2 trigger is based on fluctuating wireless channel states, the handover anticipation may sometimes be incorrect. In the case of incorrect anticipation, unnecessary buffer space may be used for the purpose of providing a smooth handover. Therefore, it is essentical to analyze these overhead costs, in order to evaluate and compare the performance of Fast Handover with that of the basic Mobile U protocol. In this paper, we analyzed the overhead associated with Fast Handover including the signaling cost and the packet delivery cost. We formulated these costs based on a timing diagram and compared Fast Handover with basic Mobile Ipv6 in terms of their packet loss rates and buffer requirements. Also, we studied the impact of the L2 triggering time on the total overhead cost.

TD-SCDMA 시스템에서의 소프트 핸드오버 적용 및 성능 분석

박재현,설붕,김덕경 한국통신학회 2008 韓國通信學會論文誌 Vol.33 No.12

TDD를 기반으로 하는 TD-SCDMA 시스템에서는 이동국이 셀과 셀 사이로 이동할 때, 통화상태를 유지하기 위해서 바톤 핸드오버(Baton Handover)를 사용한다. 하지만 바톤 핸드오버는 장비와 시스템에 더 높은 복잡도와 더 많은 계산량과 같이 많은 요구사항을 갖는다. 그래서 실제 시스템에서는 하드 핸드오버와 바톤 핸드오버를 병행하여 사용하는데 그 성공률이 95%정도로 실제 시스템에 사용하기에 부적합하다. 본 논문은 이미 WCDMA를 기반으로 성능이 증명된 소프트 핸드오버(Soft Handover)를 TD-SCDMA 시스템에 적용하는 방안을 제안한다. 또한 모의실험을 통해 기존의 바톤 핸드오버방식과 제안된 핸드오버 방식에 대한 BER성능을 측정하였다. 그 결과를 통해 제안된 핸드오버의 BER 성능이 기존의 바톤과 하드핸드오버에 비해서 좋은 성능을 가지는 것을 알 수 있다. In TD-SCDMA systems based on TDD, when mobiles move to cell from cell, Baton Handover was used to maintain an ongoing call. But baton handover has a great demand for the equipment and system. Then both hard handover and baton handover are used alternativly in real systems. But ratio of handover success in real system is 95% which is too low to be used in systems. This paper proposes to employ Soft Handover in TD-SCDMA systems which has performed in WCDMA systems. Also we carry out the simulation, which get result of the BER performance between baton handover method and proposed handover method. The proposed method is forward to be better performance than those of the baton and hard handover.

종합병원 간호사의 간호인계역량: 전남지역을 중심으로

오혜지,엄미란 한국비즈니스학회 2023 비즈니스융복합연구 Vol.8 No.1

The purpose of this study was to investigate the experiences of handover error, causes of handover error and nursing handoff competency and to identify the influencing factors for nursing handoff competency of general hospital nurses. Data were collected using a structured questionnaire from 251 nurses who agreed on the purpose of the study among nurses working at a general hospital with more than 300 beds located in Jeollanam-do. For data analysis, descriptive statistics, independent t-test, ANOVA, Scheffe test and multiple regression were used SPSS Win 27.0. As a result of this study, experiences of handover error was 27.48 points out of 64 points. The most highly regarded item was “There were too many handover contents or there were instances during which they could not be remembered”. Among the causes of handover error, “The stress or fatigue of those involved in the handover” was the item with the highest average score. The average score of nursing handoff competency was 78.31 points out of 100 points. Nursing handover competency according to the characteristics of the subjects significant differences for the age, marital status, educational level, work position, total career period, handover experience perid, work unit, handover method, and handover preparation time. Factors affecting nursing handoff competency of the subjects were shown to the experiences of handover error, master’s degree or higher, and total career period of 3 years of more. The power of explanation for this model was 31.1%. The results of this study suggest that the more nurses experiences handover error, the less efficient they nursing hanoff competency. Therefore, development of standardized handover protocols and educational interventions in various situations will be needed to improve the nursing handoff competency by reducing the experiences of handover error of general hospital nurses. 본 연구의 목적은 종합병원 간호사의 인수인계 오류경험 정도, 인수인계 시 오류원인 및 간호인계역량을 파악하고 간호인계역량에 미치는 영향요인을 확인하기 위함이다. 자료수집은 전라남도에 소재한 300병상 이상의 종합병원에 근무 중인 간호사 중 연구목적에 동의한 간호사 251명에게 구조화된 설문지를 이용하여 수집하였다. 자료분석은 SPSS Win 27.0을 이용하여 기술통계, 독립 t검정(Independent t-test), 분산분석(ANOVA), 쉐프 검정(Scheffe test), 다중회귀분석(Multiple regression)을 이용하였다. 본 연구 결과 인수인계 오류경험 정도는 64점 만점에 27.48점으로, 그 중 인수인계 오류경험 정도가 가장 높았던 문항은 ‘인계내용이 너무 많거나 기억이 나지 않은 적이 있다’였으며, 인수인계 시 오류원인으로 가장 높게 생각하는 문항은 ‘인수인계자의 스트레스나 피로가 심하다’였다. 대상자의 간호인계역량은 100점 만점에 78.31점이었으며, 대상자의 특성에 따른 간호인계역량 정도는 연령, 결혼상태, 교육 정도, 직책, 총 경력기간, 인수인계 경력기간, 근무부서, 인수인계 방법, 인수인계 준비시간에서 유의한 차이를 나타냈다. 대상자의 간호인계역량에 영향을 미치는 변수는 인수인계 오류경험 정도, 대상자의 특성 중에서 석사 이상, 총 경력기간 3년 이상으로 나타났으며, 본 모형의 설명력은 31.1%이었다. 이상의 연구 결과를 토대로 종합병원 간호사의 간호인계역량 향상을 위한 방법으로 인수인계 오류경험을 감소시키기 위한 다양한 상황의 표준화된 인수인계 프로토콜 개발 및 교육적 중재가 필요할 것이다.

군병원 인수인계 실태 및 간호사의 인수인계에 대한 인식

김선호 ( Seon Ho Kim ),김은만 ( Eun Man Kim ),정유미 ( Yoo Mi Jung ) 국군간호사관학교 군진간호연구소 2014 군진간호연구 Vol.32 No.2

Purpose : This study was conducted to identify the status of nursing handover in the ROK military hospitals and nurses` perception, experience level and causes of nursing handover errors. Methods : The subjects were 137 nurse officers and civilian nurses who were working in general wards of two military hospitals. In total, 110 data were used in the statistical analysis. Results : Only 8.2% of the respondents reported that they covered all the patients during their nursing handover process. The average handover time was 19.2±12.0 minutes. 59.8% of the respondents were found to use no written guideline or checklists during their nursing handover in the wards. The nurses perceived that their nursing handover was efficient (5.21±0.68), informative (5.13±0.69), and interactive and supportive (4.86±0.86). On the other hand, they expressed that their patients were rarely involved in the handover process (3.61±0.87). The experience of making a phone call to the preceding nurse for unclear or omitted information demonstrated the highest score (1.76±0.50) in experience related to nursing handover errors. The nurses indicated ``heavy workloads (3.54±0.96)``, ``many interruptions of handover (3.31±1.00)``, ``stress and fatigue (3.24±0.89)``, ``personal disposition (3.15±0.99)`` as the main causes of handover errors. Conclusion : The results of this study suggest that it is necessary to develop a standardized nursing handover protocol to promote patient safety by preventing errors in nursing handover.

환자 안전을 위한 요양병원 인수인계 현황에 대한 조사연구

윤정현,윤은경 사단법인 한국안전문화학회 2022 안전문화연구 Vol.- No.17

This study is related to 80% of communication errors among medical personnel among safety accidents in nursing hospitals in Korea, and 37% errors occur in the handover process of exchanging patient information between nurses. It is emphasized that there is a close relationship with With the aging society, the number of nursing hospitals is also increasing, so it was attempted to provide basic data to prepare a management strategy to improve the takeover by grasping the current status of the nursing hospital takeover. This study conducted a questionnaire survey on 102 nurses working in 4 nursing hospitals located in P city from September 30 to October 11, 2019. The collected data were analyzed using SPSS/WIN 21.0, and the reliability of the tool was measured by Cronbach's ɑ, and descriptive statistics were performed on the general characteristics of subjects and characteristics related to takeover, the degree of error experience, and the causes of errors. As for the takeover-related characteristics of the subjects of this study, 15 respondents (63.8%) answered that there is no written guideline or checklist for handover, and 'there is no written guideline or checklist on handover. There were 92 nurses (92.1%) who thought it was necessary, and as a result of the handover error experience, 'have ever been criticized or complained of from a patient or guardian due to a handover error' was 1.89±0.73. The highest score was 1.73±0.73 for 'Sometimes a shift worker said that he did not take over even though he was given a handover', followed by 'Sometimes I misunderstood the details of the handover' and 'I called to confirm because the handover was incorrect. 'Has ever been' with 1.72±0.87. As for the cause of errors in the takeover of nurses, it was found that nurses considered ‘xcessive workload’ to be the most common cause of errors during takeover with a score of 2.69±0.67. Next, 'there is no standardized handover guidelines (contents, methods)' with 2.64±0.80 and 'personal tendencies work during takeover' with 2.61±0.74, indicating human error in relation to errors occurring in the handover process. It was found that the possibility of The subjects of this study mentioned excessive workload, lack of guidelines, and human error as causes of takeover errors during takeover. Therefore, since reducing handover errors is an important factor for patient safety, we believe that standardized guidelines are needed as a method to reduce the causes of handover errors.

Multi-Objective Handover in LTE Macro/Femto-Cell Networks

Roy, Abhishek,Shin, Jitae,Saxena, Navrati The Korea Institute of Information and Commucation 2012 Journal of communications and networks Vol.14 No.5

One of the key elements in the emerging, packet-based long term evolution (LTE) cellular systems is the deployment of multiple femtocells for the improvement of coverage and data rate. However, arbitrary overlaps in the coverage of these femtocells make the handover operation more complex and challenging. As the existing handover strategy of LTE systems considers only carrier to interference plus noise ratio (CINR), it often suffers from resource constraints in the target femtocell, thereby leading to handover failure. In this paper, we propose a new efficient, multi-objective handover solution for LTE cellular systems. The proposed solution considers multiple parameters like signal strength and available bandwidth in the selection of the optimal target cell. This results in a significant increase in the handover success rate, thereby reducing the blocking of handover and new sessions. The overall handover process is modeled and analyzed by a three-dimensional Markov chain. The analytical results for the major performance metrics closely resemble the simulation results. The simulation results show that the proposed multi-objective handover offers considerable improvement in the session blocking rates, session queuing delay, handover latency, and goodput during handover.

Multi-Objective Handover in LTE Macro/Femto-Cell Networks

Abhishek Roy,신지태,나브라티색서나 한국통신학회 2012 Journal of communications and networks Vol.14 No.5

One of the key elements in the emerging, packet-based long term evolution (LTE) cellular systems is the deployment of multiple femtocells for the improvement of coverage and data rate. However, arbitrary overlaps in the coverage of these femtocells make the handover operation more complex and challenging. As the existing handover strategy of LTE systems considers only carrier to interference plus noise ratio (CINR), it often suffers from resource constraints in the target femtocell, thereby leading to handover failure. In this paper, we propose a new ef-ficient, multi-objective handover solution for LTE cellular systems. The proposed solution considersmultiple parameters like signal strength and available bandwidth in the selection of the optimal target cell. This results in a significant increase in the handover success rate, thereby reducing the blocking of handover and new sessions. The overall handover process is modeled and analyzed by a three-dimensional Markov chain. The analytical results for the major performance metrics closely resemble the simulation results. The simulation results show that the proposedmulti-objective handover offers considerable improvement in the session blocking rates, session queuing delay, handover latency, and goodput during handover.

An Improved Handover Method Using Mobile Tracking by Fuzzy Multi-Criteria Decision Making

강일고(Kang Il Ko),신성윤(Shin Seong Yoon),이종찬(Lee Jong Chan),표성배(Pyo Seong Bae),이양원(Rhee Yang Won) 한국컴퓨터정보학회 2006 韓國컴퓨터情報學會論文誌 Vol.11 No.3

서비스를 요구하는 다수의 사용자를 수용하려면 마이크로- 와 피코-셀과 같은 작은 셀로 크기를 더욱 줄이는 것이 일반적으로 수용되고 있다. 이런 환경에서는 빈번한 핸드오버가 발생하게 되고 이로 인해 허용 가능한 핸드오버 처리 지연 시간을 감소시켜 결국 패킷 손실과 핸드오버 실패를 초래하게 된다는 것이다. 또한 패킷 손실을 보상하기 위한 재전송이 필요하게 되어 시스템의 성능을 저하시킨다. 본 논문에서는 차세대이동통신시스템을 위한 새로운 핸드오버 기법을 제시한다. 이동 단말기의 현재 위치와 이동 방향을 기반으로 핸드오버 셀을 예측함으로서, 핸드오버 설정 절차가 핸드오버 요청 전에 선행된다. 시뮬레이션은 핸드오버 실패율과 패킷 손실율에 초점을 두었다. 시뮬레이션 결과를 통하여 제시된 방안이 기존의 방법보다 향상된 성능을 보임을 입증한다. It is widely accepted that the coverage with high user densities can only be achieved with small cell such as micro- and pico-cell. The smaller cell size causes frequent handovers between cells and a decrease in the permissible handover processing delay. This may result in the handover failure, in addition to the loss of some packets during the handover. In these cases, re-transmission is needed in order to compensate errors, which triggers a rapid degradation of throughput. In this paper, we propose a new handover scheme in the next generation mobile communication systems, in which the handover setup process is done in advance before a handover request by predicting the handover cell based on mobile terminal's current position and moving direction. Simulation is focused on the handover failure rate and packet loss rate. The simulation results show that our proposed method provides a better performance than the conventional method.

Analysis of Handover Latency for Mobile IPv6 and mSCTP

김동필,고석주 한국정보처리학회 2008 Journal of information processing systems Vol.4 No.3

This paper analyzes the handover latency of Mobile IP and mobile SCTP over IPv6 networks. The analytical results are compared with the performance by experiment over Linux testbed. For analysis, we consider the two handover scenarios: horizontal handover and vertical handover. From the results, we see that mSCTP can provide smaller handover latency than Mobile IP. Moreover, mSCTP can give much smaller handover latency for vertical handover, compared to horizontal handover.

Analysis of Handover Latency for Mobile IPv6 and mSCTP

Kim, Dong-Phil,Koh, Seok-Joo Korea Information Processing Society 2008 Journal of information processing systems Vol.4 No.3

This paper analyzes the handover latency of Mobile IP and mobile SCTP over IPv6 networks. The analytical results are compared with the performance by experiment over Linux testbed. For analysis, we consider the two handover scenarios: horizontal handover and vertical handover. From the results, we see that mSCTP can provide smaller handover latency than Mobile IP. Moreover, mSCTP can give much smaller handover latency for vertical handover, compared to horizontal handover.