Mobility Mechanism included Mobile Routing Method in a

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Mobility Mechanism included Mobile Routing Method in a

Wireless Mesh Network Environment

Seung-heub Jeon1, Young-bok Cho

1, Sang-ho Lee

2

School of Computer Science

Chungbuk National University, Seoul, SouthKorea

School of Electrical &Computer Engineering

Chungbuk National University, Seoul, SouthKorea

1 [email protected] ,[email protected] ,

[email protected]

Abstract

Wireless Mesh Networks dynamically forms a network and

each node connects and maintains a mesh network. The Meshnetwork is a hybrid WMNs, combined by two network mobilities which is the MANETs based Backbone WMNs and

the non-MANET based Client WMNs. This researchrecommends a routing method that provides interoperability

and effectiveness in the BWMNs and CWMNs combinedHWMNs network. This method used the same routingprotocol as the BWMNs and CWMNs network to solve theMDM problem of the node that occurs in the mobility of a

wireless environment. Also by using proxy ARP to solve the

vibration conditions that occur when connecting to BWMNsand CWMNs network, the node mobility supporting problemin the heterogeneous network was solved. It solved the twomajor problems in the previous Wireless Mesh Networks. By

using the limited routing method, the mobility was supported

by effectively intensifying the heterogeneous Wireless MeshNetworks. At the same time, as the surrounding Node number

increased, the movements of the packet transmission rate fromthe gateway stabilized compared with the previous OLSR method.

1. Introduction

A Mash Router to connect an Ad-hoc network, the internet and

other basic network is needed to implement the Wireless MeshNetwork. Also, basically two wireless interfaces are needed tocompose the Wireless Mesh Networks. One will be used as the

interface to connect with the Wireless Backbone Networks andthe other is for the communication with the user. The search

and selection of a Mash Router is a crucial issue in a WirelessMesh Networks environment where the Ad-hoc network connects with the internet and this effects the network

performance.The strong points of a Wireless Mesh Networks is the

flexibility and scalability of networks such as easy expansionof network without the connecting to the wired internet, thespeed and price of installation and the redundancy throughdiverse routes. Moreover the Wireless Mesh Networks is in

the center of attention due to the fact that it is an effectivetechnology when composing an independent network using

wireless channels or forming a relay network for internetaccess. However, currently the research on Wireless MeshNetworks security is not enough. Therefore, new technologyon security is needed. The security can be easily penetrated

since it is a broadband network, the channel and node is weak

and the network topology is dynamic. Usually the network

security is penetrated by providing the wrong routing update

information in the routing protocol. To design a keymanagement server that secures the stability of a Mesh

Network, this research provides methods that controls the

broadcast message inside the network stack of an internal nodethat exists on the network of a Mesh Network node. Thecontents of this research is as follows. On Section 2, related

research on the composition and the connection of HybridWireless Mesh Networks is described with the analysis on the

authentication plan and it's protocol for the Wireless MeshNetworks. On Section 3, shows the designed Wireless MeshNetworks and embodied mobility of a gateway. On Section 4,presents the performance analysis of the recommended systemas well as it's results. On Section 5, the conclusion and future

research plans are indicated.

2. Related work

2.1 The Structure and the Routing technology of the

Hybrid Wireless Mesh Networks(HWMNs)

The typical form of a Mesh Client Network is the MANETs.

To transmit the packet of network layers in MANETs, an

OLSR(OLSR, Optimized Link State Routing) protocol movesin the Ad-hoc link and the internet layer routing protocolmoves in the Wire-Link.

Figure 1. Hybrid Wireless Mesh Netowk r

[Figure 1] shows the connected HWMNs structure via oneMCG(MCG,Mash Cluster Gateway) that acts as the gateway

of the left CWMNs(Clinet Wireless Mesh Networks) and the

right BWMNs. Here it is connect by the Ad-hoc MANETSgateway network. The most suitable route in transmitting of packet in a network layer is the Proactive Routing method andthe Reactive Routing Method. Their typical protocols arerelatively the OLSR and the DMNO(DMNO,Dynamic Mesh

Network On-demand). If they are used with different routing

protocols, an overload problem will occur in which

2Corresponding Author

9781-4244-3428-2/09/$25.00 ©2009 IEEE



simultaneous protcol conversion must be taken in the gateway.

Therefore to perform an effective connection, the same L3routing protocol must be used in both CWMNs and BWENs.

2.2 Wireless Mesh Networks Authentication Plans

To authenticate the Wireless Mesh Networks, methods such as

using a reliable node, using a cluster and using a router was

introduced. Among them the third method which was to use areliable node is not suitable due to the fact that the nodes usedeverytime should always be reliable. The method to use cluster

classifies the Wireless Mesh Networks into cluster units and

issues authentication to each cluster header. However there isa defect that if one of the cluster header is attacked or does notplay it's role, all the nodes under it will be affected. Therouting method, routes all the nodes in the Wireless MeshNetworks as well as issues authentication. This method has the

weakness in additionally transmitting the authentication. Also

this method didn't consider the home network environmentwhere a host and a guest exists so the Wireless MeshNetworks in slow and hard to manage.

3.

Mobile Routing in a Wireless Mesh Network Environment

MS(MS,Mobile Station), a composition of MANETs, can

easily identify the wireless environment that it is located atbecause of the loaded MDM(MDM,Mode Detection

Mechanism) module. At the end, this network structure has tosupport the IP Mobility when the Mobile Node is connected tothe MANETs or when the MANETs Mobile Node is moved to

a normal access network. [Figure 2] shows the structure of aDMNO based Wireless Mesh Networks.

Figure 2. Wireless mash network structure based MYMO

As shown, the DMNO based Wireless Mesh Networksstructure does not demand additional function to the Mobile

Node for it's previous wireless environment or compatibility

and supports the mobility of the Node to it's final destinationonly when a request to transmit a packet(a key characteristicsof a DMNO routing protocol) is placed.

3.1 Wireless Mesh Cluster Gateway and Mobile Node

Each Wireless MCG moves as the administrator according tothe IEEE802.11b standard of the WLAN domain and provideswireless access service to managed mode Mobile Node. Alsoit operates on the DHCP(DHCP,dinamic Host configurationProtocol) server to automatically provide IP addresses to

primary mobile Nodes. Then to access between networks withother Wireless MCG formed by the wireless distributionsystem, each WDS interface is allocated with an independentIP address. An IP Mobility design in a DMNO protocol based

limited network is simple but supports perfectly by using the

Multi-Hop ARP method which uses the proxy ARP, RREQ of DMNO and RREP.

Figure 3 Multi-hop ARP Request and Reply step

[Figure 3] shows the Multi-Hop ARP reply by stage and the

transmitting procedure of the replied message after a Multi-Hop ARP message request in a DMNO protocol based

Wireless Mesh Networks. [Node 4] shows the procedure of acommunicating MS-1 moving to another MCG-4 domain andconnecting to L2 and finishing the ARP procedure for theprimary gateway IP address of the Mobile Node and

continuing to search the route and it's connecting Multi-Hop

ARP for the data packet that MS-1 is transmitting.

Figure 4. Multi-hop ARP Request step of support the Mobility

The proxy ARP and the Multi-Hop ARP method to support theIP Mobility didn't change the reply of a DMNO routingprotocol of a DMNO based Wireless Mesh Networks to form aroute for the package to it's final destination only on request.

3.2 Block of Malicious Node

The proposed method to secure the wireless network isconnection, encryption and a message to block maliciousnode. The connecting method is by the nodes under HWMNs

using a wireless relay method to communicate and each nodeforms a Symmetric Link to guard the data transmission of it's

neighboring node. The encryption method is by using an



asymmetric encrypting method to prevent optional reports

from other nodes. To issue an authentication, the personal keyis only known to the node himself and the public key isregistered at an authentication institution which is connected

to the HWMNs backbone and so only the nodes who share theMesh Network will know the public key. Only the nodes who

have the official authentication can report a malicious node at

the message producing stage and when reporting a node with aforged authentication, you can also identify the reporter through the authentication institute. To block a malicious node

in a WMNs environment, the message used are reporting,

disputing and proving. The messages supporting the report of a malicious node are the reporting node, the target node and amalicious node. Next, when a node who received a disputingmessage in an encrypted report and wants to send it to other nodes, he must first check if any of his target node is on and if

his name is on the list of the targeted nodes, he must broadcast

a dispute message to prove that he isn't a malicious node.Finally, a proving message is to prove the innocence of areported message and when the node who sent a reportmessage receives a disputing message, he can attach and send

a received message or data to identify the forgery or prove thereported or disputed message.

4. Experimental Results

A proxy ARP was proposed to effectively transmit a wirelessmesh cluster gateway by reducing the overload of DMNO

protocol based network and by connecting the Multi-HopARP, mobility was embodied. In a Wireless Mesh Network with the basis of a distribution system based DMNO protocol,

not only the Mobility Node but also the Wireless Mesh Cluster was able to move. Therefore, the Wireless Mesh Cluster managed the WDS link between the Wireless Mesh Cluster

gateway and drove the daemon of allocating IP addresses toWDS interface. Also to effectively manage the IP sub-

network, the Wireless Mesh Cluster gateway ran the DHCPserver and as the routing protocol to form other Wireless MeshCluster gateway and MANETs, it drove the DMNO-DCNdaemon using the callback function of a Netfilter-Hook

method. The Wireless Mesh Cluster gateway also supports the

Multi-hop ARP to support the mobility of the Mobile Nodes.If the RREQ message found by using the DMNO-DCNdaemon is received through the DMNO socket in the middleof the Wireless Mesh Cluster gateway, the DMNO daemon

stores the routing entry of the pocket's origin IP address in therouting table and rebroadcasts the RREP message. Also when

the destination Node receives the RREQ message via DMNOsocket, DMNO daemon stores the routing entry of the pocket'sorigin IP address in the routing table and rebroadcasts the

RREP message.

4.2 Performance & Mobility According to the Increase of

Hop & Node Numbers

Two Wireless Mesh Networks were placed each at the2500*2500(m) range from the gateway and 60 Mobile Nodethat composes each network were optionally allocated. Then

the packet loss of OLSR and the DMNO were analyze byincreasing one hop of two communicating Mobile Node fromthe gateway. Also to experiment the mobility, the WirelessMesh Cluster gateway were given the same Extended ServiceSet ID and channels to manage an independent IP sub-network.

To identify the practical transmission of the data packet, thepacket analyzer was turned on for two Mobile Node and four

Wireless Mesh Cluster gateway. As shown in the graph of [Figure 5], OLSR shows increase of packet loss between thetwo Mobile Node according to the increase of hop numbers

from the gateway. This goes in line with the fact that as the

hop numbers increases the relocating time for the network routing table increases as well. On the other hand, you can seethat there is no packet loss for DMNO since it only sets the

route for the requested destination without having to relocatedthe network route.

Figure 5. Pack delivery rate of increase around number of node

On the graph of [Figure 6], you can see that for OLSR, thepacket loss rapidly increases along with the increased number of Mobile Node. This goes in line with the fact that as the

number of communicating Mobile Node increases thecontrolling data to find the network's destination route alsorapidly increases.

Figure 6. Hop count increment to gateway

Figure 7. Routing table of two node befor moving



The routing table of the two communicating Mobile Node is as

[Figure 7]. The basic gateway of the two Mobile Node isidentical to the Wireless Mesh Cluster gateway that controlstheir relative IP addresses.

Before moving, Ping was performed from MS-2 to MS-5 andthe captured packed from the two Mobile Node were

transmitted by the most suitable route in the middle of the

Mesh gateway as the data packet and provided transparency tothe two Mobile Node. If the communicating Mobile Node MS-5 moves to the IP network of the middle Wireless Mesh

Cluster gateway MCG-4, it will be connected with the

physically linked wireless mesh cluster gateway and the basicgateway IP address of the routing table will be the previous IPaddress of the Wireless Mesh Cluster gateway. Therefore theproxy ARP of the moved Wireless Cluster gateway MCG-4will activate normally. The routing table of the middle

wireless mesh cluster gateway will move from MS-2 to MCG-

4 and after the procedure of proxy ARP, the data packet willcontinuously be transmitted to MCG-4 and then the MCG-4will form new routes using the Multi-Hop ARP method whichis connected with the routing search of DMNO daemon.

5. Conclusions

The structure of the wireless network for the next generationwill be a mixed heterogeneous wireless network of different

characteristics and services. As the scale of the wirelessnetwork expands, the former OLSR protocol method of

transmitting packets will rapidly increase the confusion of thenetwork and eventually the efficiency of the network willdrop. Therefore the proposed DMNO based wireless Mesh

networks of this research will be an alternative to solve thisproblem. The wireless mesh clusters will form a DMNOprotocol based wireless Mesh Networks and to provide

wireless access service to the former mobile nodes withoutdemanding any additional function, the wireless mesh cluster

gateway will be based on an wireless infrastructureenvironment. Also the managed mode mobile node should beprovided with continuous IP mobility as they move freelyacross the Wireless mesh cluster gateway. This research

introduced an expanded multi-hop ARP method to provide

effective IP Mobility to mobile nodes by using proxy ARP andDMNO protocol routing search procedures. Also the mobilitymovement was embodied on the basis of linux system. As aresult, this research showed how this Heterogeneous wireless

mesh network can maximize the effectiveness of the network

and provided a guideline when designing a Wireless MeshNetwork.

6. References[1] He, Z.L, Tsui, C.Y., Chan, K.K., and Liou, M.L.,

“Low-power VLSI design for motion estimation usingadaptive pixel truncation”, IEEE Trans. Circuit Syst.

Video Technol. 10(5):669-678, 2000.

[1] Song, Z., Roussopoulos, N. "K-Nearest Neighbor Searchfor Moving Query Point".SSTD, 2001.

[2] Zheng B., Lee, D. "Semantic Cachng in Locatikdar, B.; "Aprotocol for tracking mobile targets using sensor

networks". Proceedings of the First IEEE. 2003

Page(s):71 – 81

[3] Xu, Y.; Winter, J.; Lee, W.-C.; "Dual prediction-based

reporting for object tracking sensor networks".Proceedings of MOBIQUITOUS 2004. Page(s):154 – 163

[4] Paolo Santi,“Topology Control in Wireless Ad Hoc and

Sensor Networks,”WILEY

[5] Seema Bandyopadhyay, E.J. Coyle,"An Energy Efficient

Hierarchical Clustering Algorithm for Wireless Sensor

Networks" Infocom 2003, IEEE Vol 3, 30 Mar-3 April2003 Page(s):1713-1723

[6] Cho Young-bok, Lee Sang-ho, An Energy EfficientClustering Scheme of Mobile Sink Node in Wireless

Sensor Networks, Preceedings of the 7th WSEAS

International Conference on CIRCUITS, SYSTEMS,ELECTRONICS, CONTROL and SIGNALPROCESSING(CSECS 08)Puerto De La Cruz, Tenerife,Canary Islands, Spain, ISBN: 978-960-474-035-2,

December 15-17, 2008, pp. 317-320[7] Young-Bok Cho, Sung-Hee Woo, Sang-Ho Lee, Efficient

Key Distribution Scheme for Secure Routing in WirelesMesh Network Environment, Proceeding of the 7thWSEAS International Conference on INFORMATION

SECURITY and PRIVACY (ISP '08) Cairo, Egypt,ISBN: 978-960-474-048-2, Dec, 29-31, 2008, pp. 79-82

[8] YOUNB-BOK CHO, YOON-SU JEONG, SANG-HOLEE, Dynamic Prediction Clustering Scheme for MobileSensor Node of Sensor Network Environment, THE 11th

INTERNATIONAL CONFERENCE on ADVANCEDCOMMUNICATION TECHNOLOGY, Phoenix Park,Koren, ISBN: 978-89-5519-139-4, Feb, 15-18, 2009, pp.

266-270

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