• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.32 no.6A
• /
• pp.632-641
• /
• 2007

Since the mobile node acts as the router, the Mobile Ad Hoc network requires the security methods that are different from that of network of the wire environment. Also, since the total network can't be included in the transmission area of the mobile node, when one node sends the message to the other node, we need the middle node. But if the middle node is the unreliable malicious node, we can't guarantee the secure message transmission. Also, because all nodes configuring the network are the mobile nodes, they use the restricted battery capacity and the restricted resources. Therefore, because we have trouble performing the encryption that many resources are required when we sending the message, it is vulnerable to the security than the network of the wire environment. Last, because the network topology continues to change by the mobility of nodes configuring the network, we need the security measure that matches the network characteristics. We suggest the routing attack detection for performance enhancement of AODV protocol in Mobile Ad Hoc networks.

• Convergence Security Journal
• /
• v.13 no.4
• /
• pp.41-46
• /
• 2013

Routing protocol using in the existing wire network cannot be used as it is for efficient data transmission in MANET. Because it consists of only mobile nodes, network topology is changing dynamically. Therefore, each mobile node must perform router functions. Variety of routing attack like DoS in MANET is present owing to these characteristic. In this paper, we proposed cooperative-based detection method to improve detection performance of flooding attack which paralyzes network by consuming resource. Accurate attack detection is done as per calculated adaptively threshold value considered the amount of all network traffic and the number of nodes. All the mobile nodes used a table called NHT to perform collaborative detection and apply cluster structure to the center surveillance of traffic.

• Journal of information and communication convergence engineering
• /
• v.8 no.1
• /
• pp.1-5
• /
• 2010

In this paper, we propose for improving QoS in wireless micro cellular network using Cellular-IP/PRC(Paging Route Cache) with Paging Cache and Route Cache in Cellular-IP and propose for performance of realtime and non-real time handoff service using Handoff state machine Paging Route Cache. Although the Cellular-IP/PRC technology is devised for mobile internet communication, it bas its vulnerability in frequent handoff environment. On the other hand, Cellular IP combines the capability of cellular networks to provide high performance handoff and efficient location management of active and idle mobile users with the inherent flexibility, robustness and scalability found in IP networks. Also Cellular-IP/PRC use semi-soft handoff. During semi-soft hand off a mobile host may be in contact with either of the old and new base stations and receive packets from them. Packets intended to the mobile node are sent to both base stations and buffered, so when the mobile host eventually moves to the new location it can continue to receive packets without interruption. It should be suitable for realtime service such as multimedia traffic. But, much waste of resource will occur in this method, especially for non-real time services such as FTP and E-mail. Therefore, a new algorithm that performs different handoff according to characteristic of each traffic by use of reserved field in IP packet is proposed in this thesis. This hand off state machine using differentiated handoff improves quality of services in Cellular-IP/PRC. Suggested algorithm shows better performance than existing technology in wireless mobile internet communication environment. Matlab simulation results are improving QoS, show call drop and call blocking provided to Paging Router Cache during handoff state machine in Cellular-IP/PRC.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.12 no.6
• /
• pp.229-240
• /
• 2012

The development of multimedia applications followed by development of high-speed networks has improved the performance of mobile devices with high transfer speed broadband. Mobile internet access has made possible seamless indoor and outdoor mobile multicast services. Multicasting services are used to support efficient group communications. However, mobile multicasting services have two constraints: tunnel convergence and handover latency. Many protocols and handover methods have been proposed to address these problems. The inter-LMA optimized handover model for multicasting services has previously been proposed for PMIPv6-based networks. The proposed model removes the tunnel convergence issue and reduces router processing costs. It also makes possible the performance of fast handover operations with adaptive transmission mechanisms. In addition, the proposed scheme exhibits low packet delivery costs and handover latency in comparison with existing schemes, and ensures fast handover when moving the inter-LMA domain

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.10B
• /
• pp.927-937
• /
• 2003

Network based VPN(Virtual Private Network) using MPLS(Multiprotocol Label Switching) technology is regarded as a good solution for intranets or extranets because of the low cost and the flexibility of the service provision. In this paper, we describea mechanism that allows the VPN users to move from one site to another site of the VPN network based on the BGP-E MPLS technology. This mechanism is designed for and implemented on PE(Provider Edge) routers of the backbone network. PE routers connected to the VPN sites establish a new MPLS path to the mobile node after they detect movement of the mobile VPN node. The new location may belong to the same VPN or to different VPN. We designed VPN management and control functions of the PE routers in order to interface with the Mobile IP protocol. The pilot implementation and performance measurement were carried out on a testbed.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.43 no.6 s.348
• /
• pp.9-22
• /
• 2006

When the legacy multicast routing protocols are adopted in If-based mobile core networks, there are some problems such as traffic injection from unnecessary sources, traffic overhead by group management and router performance degradation by large amount of multicast session information. In this paper, we propose a stateless multicast mechanism which has no need to maintain multicast information for session status and reduces redundant network overhead for maintaining multicast tree. In addition interworking with IGMPv3 gets rid of traffic from unnecessary sources which have no registration from receivers. The operations of essential components including a gateway node for interworking with the legacy Internet multicast network, a gateway node for transparency to radio access network and a intermediate node in mobile core networks, are definitely defined and the proposed communication architecture is completed. Finally we evaluate and approve the performance of the proposed architecture by means of well-designed network simulation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2007.10a
• /
• pp.75-78
• /
• 2007

Mobile IP provides hand-held devices with mobility which allows the user to do work over the network. However, handover time due transfer between access routers causes network delays and data loss. L2Trigger Handover expects this handover to take place, and executes L3 handover before L2 handover takes place, thereby reducing overall handover latency, although it still is an issue since handover latency between AR is not completely eliminated in L2 trigger handover. In this paper took into consideration where MIH is used in MIPv4 and using MIH Table when handover is about to occur in MN(Mobile Node), thereby pre-fetching data needed by Handover. In this way, when the handover is estimated, it improves the init time that L2trigger had. Furthermore we can find that we can execute the handover with shorten init time in smaller and narrow overlap length

• The Journal of Korean Association of Computer Education
• /
• v.10 no.5
• /
• pp.81-88
• /
• 2007

To support the movement of a mobile network consisting of several mobile nodes, the IETF NEMO working group proposed NEMO basic support protocol using bi-directional tunneling between the home agent and the mobile router. Since NEMO basic support protocol is based on bi-directional tunneling, all communications to and from mobile nodes are suffer from inefficient routing all the cases. To solve the routing inefficiency problem, several proposals are proposed. However, those proposals results in new problems, such as binding update storm and changes in existing protocol. Especially, binding update storm problem may cause the delay in binding update, this subsequently causes the difficulty for a real time service and the handoff delay on the movement of mobile network. In this paper, we propose a new binding update scheme which reduces binding update latency and the handoff delay through the distribution of the transmission time of binding update messages. The performance of the proposed scheme is also evaluated to demonstrate its efficiency. Simulation results show that the proposed scheme can efficiently reduce the binding update latency.

• Journal of KIISE:Information Networking
• /
• v.36 no.4
• /
• pp.309-321
• /
• 2009

Nowadays, requests of connecting to the Internet while moving are increasing more and more, and various technologies have been developed for satisfying those requests. The IETF nemo WG standardized "Network Mobility Basic Support Protocol" for supporting mobile network through extending existing MIPv6 protocol for supporting host mobility. But, mobile networks can be nested while they are changing their location. And if they are multi -level nested, that causes some problems because of protocol characteristic. In this paper, we try to solve the problem that is complicated routing path caused by multi-level nesting of mobile networks with our limited prefix delegation method. We give a little modification to the standard protocol and add some functions to mobile router. With results from analysis, we could say that our method has better performance than other proposed methods.

• The Journal of the Korea Contents Association
• /
• v.10 no.2
• /
• pp.120-129
• /
• 2010

MANET(Mobile Ad Hoc NETwork) is a collection of mobile nodes that are free to move and organize themselves in an arbitrary manner without any fixed infrastructures. These mobile nodes are connected by wireless links and act as routers for all other nodes in the network. As a router each node in MANET consumes its batteries when forwarding a message, and the selection of the best path to minimize the total power needed to route packets is needed to maximize the lifetime of all nodes. In this paper, we propose a routing protocol considering the remaining battery capacity of nodes in the routing paths. The proposed scheme prevents the battery of each node from being overused and increases the lifetime of the network.