• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.6B
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• pp.592-599
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• 2011

Proxy Mobile IPv6 (PMIPv6) is the network-based mobility management protocol that network supports the mobility of mobile node (MN) on behalf of the MN. In PMIPv6, a multi-homed MN can connect to the PMIPv6 domain by using only one interface even though it has multiple interfaces. It would be efficient when such a multi-homed MN connects to the PMIPv6 domain by using all of its interfaces. If such a multi-homed MN utilizes all of its interfaces, flow mobility can be provided that the MN handovers one or more flows from one interface to another without re-establishing session. In this paper, we propose the flow-based mobility management protocol by considering the intention of the user. The Router Advertisement (RA) message is used in order for the PMIPv6 domain to inform that the MN can utilize the flow mobility. The proposed mechanism is evaluated by analyzing signaling overhead and handover latency, and the numerical results show that the performance is affected by mobility speed of the MN and the failure probability of the wireless link.

• Journal of the Korean Regional Science Association
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• v.40 no.3
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• pp.75-93
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• 2024

This study examines the impact of moving to an opportunity-rich area on an individual's wage income to identify the relationship between regional disparities in opportunities throughout a person's life cycle and life outcomes. Based on the Graduate Occupational Mobility Survey (GOMS) provided by the Korea Employment Information Service, individuals with similar life experience prior to regional mobility were selected and analyzed using the Propensity Score Matching (PSM) method. Specifically, the life cycle was classified into stages such as pre-high school, university entrance period, and employment period. Then, a path model was established to analyze regional mobility, education, employment, and wage income by life cycle stage. The analysis results indicate that the life cycle stage where regional mobility had the greatest impact on an individual's economic performance, that is, the stage where the impact of opportunity disparities was most unequal, was the university entrance period. Additionally, moving to an opportunity-rich area was a critical factor that cumulatively affected subsequent life. Hence, pre-high school mobility was also noteworthy as it induced life in the central area later on. Lastly, while parental income itself was influential, but when combined with regional mobility, it could act as a means of transferring wealth to the next generation. These results suggest that the state should strive to alleviate the regional imbalance around universities by fostering universities outside the capital region and reduce the possibility of the influence of parents' socio-economic background on regional mobility.

• Journal of Communications and Networks
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• v.6 no.4
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• pp.331-342
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• 2004

We study the problem of controlling data overhead of mesh-based multicast ad hoc routing protocols by adaptively adding redundancy to the minimal data overhead multicast mesh as required by the network conditions. We show that the computation of the minimal data overhead multicast mesh is NP-complete, and we propose an heuristic approximation algorithm inspired on epidemic algorithms. In addition, we propose a mobility-aware and adaptive mesh construction algorithm based on a probabilistic path selection being able to adapt the reliability of the multicast mesh to the mobility of the network. Our simulation results show that the proposed approach, when implemented into ODMRP, is able to offer similar performance results and a lower average latency while reducing data overhead between 25 to 50% compared to the original ODMRP.

• ETRI Journal
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• v.30 no.5
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• pp.685-695
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• 2008

The Network Mobility (NEMO) and IPv6 over Low power WPAN (6LoWPAN) protocols are the two most important technologies in current networking research and are vital for the future ubiquitous environment. In this paper, we propose a compressed packet header format to support the mobility of 6LoWPAN. Also, a Lightweight NEMO protocol is proposed to minimize the signaling overhead between 6LoWPAN mobile routers and 6LoWPAN gateways by using a compressed mobility header. Performance results show that our Lightweight NEMO protocol can minimize total signaling costs and handoff signaling delay.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.8B
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• pp.738-749
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• 2003

Mobile IP protocol introduced in RFC3344 provides a node of the mobility service through IP tunneling mechanism in the IP networks. In this paper, we describe a method to provide a mobility service for VPN(Virtual Private Network) nodes on the MPLS(Multiprotocol Label Switching) network. The MPLS VPN considered here is based on "BGP/MPLS VPNs" presented in RFC2547. PE(Provider′s Edge) routers, which are able to provide VPN services on the MPLS network, are associated with mobility agents to support Mobile IP This proposed mechanism applies when a VPN node moves to other site of the same VPN, or when it moves to other site of a different VPN, or to the ordinary Internet site. We implemented this mechanism in PE routers and analyzed the performance of the MPLS VPN with mobility support on the testbed.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.3
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• pp.171-177
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• 2012

Network mobility support has been taken into consideration for users who have multiple terminals to enjoy the seamless connectivity. This paper proposes a network mobility support scheme in the LISP architecture. During the mobile router attachment, the EID-to-RLOC mapping database is refreshed in the map server. Furthermore, map update is developed to support smooth handoff for the mobile network. An analysis of performance is given by comparing the proposed scheme with NEMO.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.4
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• pp.1661-1678
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• 2016

Clustering is one of the key technologies in vehicular networks. Constructing and maintaining stable clusters is a challenging task in high mobility environments. DWCM (Distributed and Weighted Clustering based on Mobility Metrics) is proposed in this paper based on the d-hop dominating set of the network. Each vehicle is assigned a priority that describes the cluster relationship. The cluster structure is determined according to the d-hop dominating set, where the vehicles in the d-hop dominating set act as the cluster head nodes. In addition, cluster maintenance handles the cluster structure changes caused by node mobility. The rationality of the proposed algorithm is proven. Simulation results in the NS-2 and VanetMobiSim integrated environment demonstrate the performance advantages.

• Particle and aerosol research
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• v.10 no.1
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• pp.33-43
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• 2014

A differential mobility analyzer (DMA) has been widely used as a standard tool for classifying nanoparticles with a certain size. More recently, several new types of DMA have been tested in an attempt to produce size-monodisperse nanoparticles. It is a bit surprise to see how simple the working theory of the DMA is. Although the theory was demonstrated quite successful, no one can guarantee whether the theory still works in another geometry of the DMA. In this regard, we first investigated the validity of the theory under various working conditions and then moved to check the validity upon minor change in its design. For the valid test, we compared the results with those obtained from a computational fluid dynamics.

• Journal of information and communication convergence engineering
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• v.5 no.3
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• pp.209-214
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• 2007

In this paper, we proposed a new MANET (Mobile Ad hoc Networks) technology of routing protocol. The MANET has a mobility formation of mobile nodes in the wireless networks. Wireless network have two types architecture: the Tree based multicast and shared tree based. The two kind's architecture of general wireless networks have difficult to solve the problems existing in the network, such as connectivity, safety, and reliability. For this purpose, as using that ADDMRP (Ad hoc network Doppler effect-based for Dynamic Multicast Routing Protocol), this study gives the following suggestion for new topology through network durability and Omni-directional information. The proposed architectures have considered the mobility location, mobility time, density, velocity and simultaneous using node by Doppler effects and improved the performance.

• Journal of Korea Society of Industrial Information Systems
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• v.18 no.1
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• pp.1-9
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• 2013

Most calls of a called user are invoked by the group of calling users. This call pattern is defined as call locality. Similarly Internet sessions including IP telephony calls have this pattern. We define it session locality. In this paper, we propose a caching scheme to support session locality in hierarchical SIP networks. The proposed scheme can be applied easily by adding only one filed to cache to a data structure of the SIP mobility agent. And this scheme can reduce signaling cost, database access cost and session setup delay to locate a called user. Moreover, it distributes the load on the home registrar to the SIP mobility agents. Our performance evaluation shows the proposed caching scheme outperforms the hierarchical SIP scheme when session to mobility ratio is high.