Three Layer MIPv6 (TLMIPv6): a new Mobility Management Protocol for

IPv6 Based Network

1Nitul Dutta,2Iti Saha Misra, 3Md. Abu Safi, 4Kushal Pokhrel 1 Department of Computer Sc. and Engg., Sikkim Manipal Institute of Technology, Sikkim, India

2,3 Department of Electronics and Tele-Comm Engg., Jadavpur University, Kolkata, West Bengal, India 4 Department of Electronics and Communication Engg., Sikkim Manipal Institute of Technology, Sikkim, India

Abstract - Uninterrupted connectivity on move is a primary demand of end users both in cellular and IP based networks. Protocols that assist to maintain continuous link despite of frequent change in point-of attachment of mobile devices are called mobility management protocol. Although the mobility management protocols are matured enough in cellular network it is in a growing phase for IP based network. In this paper a new mobility management scheme called Three Layer MIPv6 (TLMIPv6) is proposed and comparative performance evaluation is carried out with MIPv6 and HMIPv6 protocol using simulation in ns-2 environment. The intention of this work is to analyze these three protocols and to find suitable scenario for each of these protocols. Keywords- Layered MIPv6, Performance Analysis, Simulation, ns-2.

I. Introduction To provide uninterrupted connectivity to mobile users,

support of mobility management by network layer protocols is a must. The enhancement of mobility support in a network layer protocol enables mobile devices to use the same network layer address throughout the globe. The first version of mobility aware protocol which is introduced in IPv4 [1], known as Mobile IPv4 (MIPv4) [2] or MIP was standardized by Internet Engineering Task Force (IETF). MIPv4 brought together two of the world’s most popular technologies, the Internet and mobile communication. It is most often found in wired and wireless environments where users need to carry their mobile devices across multiple Local Area Network (LAN) [3] segments. With increasing growth of wireless network deployment, seamless mobility for users becomes the need of the hour. To fulfill the demands of mobile users there are many mobility management mechanisms suggested for providing seamless mobility in wireless networks. The efficiency of these mobility management protocols are measured by handoff latency suffered by a mobile user during handoff, signaling cost involved to complete the handover process and tunneling cost (or packet delivery cost) to deliver a packet to a mobile user located outside its permanent network. Handoff latency is measured as the time taken to reestablish the connection by a Mobile Node (MN) with its Correspondent Node (CN) during changeover of one

point-of attachment [1]. Least possible handoff latency is a desirable property of any mobility management protocol. Signaling cost for mobility management is measured as the bandwidth consumed by managerial packets to complete the handover process. Similarly, the tunneling cost is measured in terms of extra bytes added to the original packet to deliver it to the new location of the MN in a foreign network. Minimized signaling cost and tunneling cost are another two requirements of mobility management protocols. With the introduction of IPv6 [4] as an alternative of IPv4 with the support of security and large address space, Mobile IPv6 (MIPv6) [5] becomes the targeted mobility management protocol for next generation IP based wireless networks. However, MIPv6 is found unsuitable for an environment where users frequently change their location within a local domain due to larger handoff latency and signaling cost.

To reduce handoff latency and signaling load, MIPv6 is extended to Hierarchical MIPv6 (HMIPv6) [6]. HMIPv6 divides the Internet into two parts; the Internet backbone, (or global domain) constructed by all border gateways in the Internet and, the Internal network, (or local domain) comprises of all outers under the coverage of single border gateway. Again, HMIPv6 classifies the mobility of MNs into micro mobility and macro mobility. The micro mobility is defined as the movement of MN from one subnet to another nearby subnet within the same local domain. Whereas the by macro mobility is defined as the movement of MNs from one local domain to another local domain. HMIPv6 introduces a Mobile Anchor Point (MAP) at the boundary of the local domain to restrict the movement of binding related messages within the local domain as long as MN stays within the same border gateway. It is the protocol that introduces the layered concept in mobility management for IPv6 based network. However, HMIPv6 does not perform well when nodes frequently change their subnet within the same local domain. Because, in such cases MAP need to be updated with the new point-of attachment by exchanging binding management messages. It increases the signaling load in the local domain. As a solution, the concept of multi layered hierarchical model in IPv6 based network for mobility management have been introduced.

In our previous work [7, 8], it is stated that, a three layer model is suitable for mobility management with optimized values of handoff latency, signaling cost and tunneling cost. The objective of the research presented in this paper is to propose a new mobility management

Acknowledgement: This work is supported by All India Council for Technical Education (AICTE), New Delhi, India, under Research Promotion Scheme (RPS) F.No.: 8032/BOR/RID/RPS-29(NER)/2011-12.

978-1-4673-1344-5/12/$31.00 ©2012 IEEE

architecture called the Three Layer MIPv6 (TLMIPv6) and to evaluate the performance of model in terms of handoff latency, signaling cost and packet tunneling cost through simulation. A comparative study of these parameters is also carried out with MIPv6 and HMIPv6. The aim of this research work is to realize the benefits of using the new model as the architecture for next generation wireless mobile network.

Rest of the paper is organized as follows. Section II is the related work, III gives the network architecture of MIPv6, HMIPv6 and the TLMIPv6. Details of ns-2 simulation setup are available in section IV. Results are discussed in section V. The paper is concluded in section VI.

II. RELATED WORK Although there are ample number of papers available

in MIPv6 based mobility management, in this section two categories of such protocols are considered for discussion. The first category is the hierarchical solution [9, 12, 13, 14, 15, and 16] and the second category is comparative studies of different mobility management protocols for MIPv6 based network [17, 19].

The proposal made by Deeya et. al. in [9] is a two layered model integrating Fast Handover for MIPv6 (FMIPv6) [10] and Session Initiation Protocol (SIP) [11]. This model is designed for real-time data communications in mobile environment. The proposed scheme reduces packet loss for an ongoing real-time data transfer during handoff. In this scheme, end-to-end negotiation is implemented within the SIP proxy for quality of service provisioning. The session re-establishment process enables CN to redirect all its ongoing streams to the MN’s CoA. The Re-INVITE message introduced in the model contains updated contact field where the MN will receive SIP messages in future. If the CN responds with an SIP OK message, agreeing to INVITE response, the MN will in turn respond with an ACK to complete the SIP. The proposed integrated scheme aims at avoiding triangular routing and any kind of encapsulation mechanism during the ongoing calls to reduce extra delays. It also reduces the signaling loads by integrating the redundant messages from both FMIPv6 and SIP for ongoing calls.

The hierarchical arrangement of anchor agents reduces handoff latency and signaling cost but increases tunneling cost. Sangheon Pack et. al in [12] performed a mathematical analysis on hierarchical MIPv6 network. They formulate the location update cost and the packet delivery cost in the multi-level HMIPv6. Based on the formulated cost functions, the authors have presented a hierarchical solution to minimize the total cost of handoff management in IPv6 network. The numerical results stated in the paper depict various relationships among network size, optimal hierarchy, and signal to mobility ratio, etc. They have suggested that their findings may be utilized to design the optimal HMIPv6 network.

The focus of the work [13 (ISM)] is to provide hierarchical mobility management solution for MIPv4 network. For this purpose, a very preliminary

mathematical analysis and simulation study is done on a hierarchical model. The Foreign Agents (FA) defined in MIPv4 is organized in pyramid like structure to form a layered architecture. There is a single FA at the Root (RFA) and multiple FAs are present in the lower layers. To see the performance of the proposed architecture the multi layered architecture is examined under various network conditions. A number of network parameters like location update frequency, handoff latency and signaling overhead are evaluated in this research through mathematical analysis and ns-2 simulation. Results indicate that three level of hierarchy in the pyramid structure shows optimal tendency in performance.

In this paper [14] authored by Yong Gan et. al., an optimized hierarchical mobile routing management model based on HMIPv6 is proposed. The messages used in the model are extensions of HMIPv6 and in FMIPv6 messages. They make use of hierarchical anchor agents to reduce signaling load by introducing the border router to realize route optimization. Fast handover in intra-domain and inter-domain is achieved in the proposed model by combining the advantages of HMIPv6 and FMIPv6. The concept of multicasting is also used in the model to reduce packet loss. The model is simulated in ns-2 network simulator. The simulation results show that the new model can reduce the handover delay and packet loss rate compared to the MIPv6 protocol.

Kawano et. al. in [15] suggest a scheme for Mobile Anchor Point (MAP) selection method in a simple tree-based hierarchical network. According to the proposed scheme, actual networks have some redundancy in structure. This type of network is considered as a complicated structured network. In such a complicated structured network, the MAP domains intricately overlap each other. This causes difficulty in selecting the MAP suitable for managing the mobile node’s mobility. They have proposed a method to allow an MN to select the suitable MAP in such a network by adjusting the selection criteria individually configured for use at a particular place. The performance of the proposed scheme is evaluated using simulation experiments. The simulation results show that the new scheme works well in complicated structured networks.

In their research article [16], Saha et. al. suggest an improved hierarchy based mobility management scheme called Three-level Hierarchical Mobile IP (THMIP). They have used fluid flow mobility model to sketch the movement pattern of users in their work. The signaling overhead for frequently moving MNs within its hierarchical domain is studied. In this scheme, the MN sends the binding update to the HA only for the first time when the CoA gets changed. From the next movement onwards, it sends binding update to the previous MAP. A mathematical analysis of the signaling load and the packet delivery cost is carried out in the work. The performance of the proposed protocol is compared with other existing mobility management protocols and the THMIP shows a considerable improvement over the others in the context of location update and packet delivery cost.

In [17], Jong-Hyouk Lee et. al. presents comparative

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analysis of HMIPv6 and Proxy MIPv6 (PMIPv6) is done [18]. A cost based evaluation model is developed and discussed in the paper. They evaluate the location update cost, the packet delivery cost, and the wireless power consumption cost based for both the protocols. Through the numerical analysis, the authors have discussed the impact of the various system parameters. The results demonstrate that PMIPv6 always outperforms HMIPv6 due to its ability to avoid the mobility signaling sent by the mobile host and it also generates reduced tunneling overhead during communications with other nodes. Another work similar to [17] is found in the work of Myung-Kyu Yi as discussed in [19]. They have investigated the performance of the PMIPv6 and have compared it with that of HMIPv6, using analytic approach considering random walk mobility of the user. Based on the analytical model, the location management cost and handoff management cost is formulated. The numerical results show that the PMIPv6 has superior performance to HMIPv6 in terms of latencies for location update and handoff.

From the above discussion on existing literature of IPv6 mobility management mechanisms, it is seen that the layered architecture has a strong potential as a solution of mobility management in next generation IP network. Looking at the importance, a new three layer model is proposed in this work. The model proposed in this paper uses three layers of MAP organized hierarchically in the local domain. In the next section we are presenting the proposed three layered model for mobility management in IPv6 network.

III. NETWORK ARCHITECTURE In this section a brief discussion of the proposed Three

Layer MIPv6 (TLMIPv6) architecture is given with a brief description of MIPv6 and HMIPv6.

A. Mobile IPv6 To support mobility, MIPv6 model uses a Home

Agent (HA) in and an Access Router (AR) [5]. The HA keeps track of all the MNs under its coverage which visits some foreign network. On the other hand, AR provides assistance to the visitor MN in a foreign network. The visitor MN in a foreign network acquires care-of address from the AR of that region and sends Binding Registration message to the HA stating the new temporary address of the MN. The HA, on receipt of the binding message, sends a Binding Acknowledgement (BACK) to the MN, to acknowledge the receiving of location information to MN. Once the binding is completed the MN can receive data using the new address in the foreign network. When an MN changes its location from one AR to another, it has to acquire a new IP address and the new location information has to be communicated to the HA again. Since, the MN and the HA are located far apart the binding process takes a longer time. In MIPv6, these messages have to traverse both the internal and backbone network to complete the handover process, so the visitor MNs suffer longer handoff delays. The signaling load due to mobility management is also more in MIPv6. So, MIPv6 is not suitable for handoff management in IPv6

based network.

B. Hierarchical Mobile IPv6 The HMIPv6 architecture is shown in Fig 1. The hierarchical MIPv6 protocol divides the network into two sections, macro mobility domain and micro mobility domain. An anchor agent called Mobile Anchor Point (MAP) is placed at the boarder of the micro mobility domain. It provides the transparency of visiting MNs to HA as well as to CNs. When a MN visits a foreign network, it acquires a Care-of-Address (CoA) and a Regional CoA (RCoA) from Router Advertisement (RA) beacon [6].

Fig. 1 Hierarchical Mobile IPv6

The address of MAP or the RCoA is notified to the visitor MN’s HA as well as to CN if any, by sending Binding Update (BU) messages. Both, the HA and CN acknowledge MN for its BU request. Once this process of request and acknowledges are over, MAP receives all packets on behalf of the MN as long as it stays within its service area. The MAP encapsulates and forwards them directly to the MN’s current address. If the MN changes its current address (i.e. LCoA) within the same MAP, HA or CNs (if any) need not be updated because HA and CNs are aware only of RCoA not LCoA and the RCoA does not change as long as the MN moves within the same MAP domain. It minimizes the signaling load in the backbone network.

C. Three layer MIPv6: TLMIPv6 The MAP located in the micro mobility domain

significantly reduces the signaling cost from handoff management as compared to MIPv6. However, the MN moving frequently from one AR to another, within the same micro mobility region, imposes a significantly large signaling load in the micro mobility domain. To further reduce the handoff latency and signaling load, more number of MAPs may be placed hierarchically in the micro-mobility domain. Since, layered MAP increases packet delivery cost to visitor MN, the number of layers in the domain must be limited up to certain levels. In our previous work [7, 8] it is shown mathematically and

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through simulation analysis that three layered hierarchical model shows optimality in terms of handoff latency, signaling load and packet delivery cost. The proposed model in this work is based on those work and the Three Layer MIPv6 (TLMIPv6) model, which is a special case of the model described in [7] and [8].

The architecture of TLMIPv6 is shown in Fig. 2. The network is divided into backbone and internal domain. The internal domain is again subdivided into local, regional and global domains. There are three different anchor agents (anchor points) to cover these three regions. An agent called MAP as in HMIPv6 covers local domain, a Regional MAP (or RMAP) covers a regional domain and a Global MAP (GMAP) [7] covers a global domain. The MAP provides local CoA (LoCoA), the RMAP provides regional CoA (RCoA), and the GMAP provide a global CoA (GCoA) to every visitor mobile node.

Fig. 2 TLMIPv6 Architecture

All anchor agents in the internal domain are organized hierarchically in the form of tree with a single GMAP as the root of the tree. The level of the GMAP is considered as layer-3, RMAPs are located in the layer-2, and MAPs are located in layer-1. All ARs are connected to MAP and ARs serve MNs within its subnet. The AR periodically transmits RA messages which comprises of GCoA, RCoA and LoCoA. Visitor MNs construct their Link CoA (LCoA) from the information contained in the RA. After constructing the LCoA, MN sends one BU packet to MAP specifying the new address, permanent IP address and HA. The MAP enters the information of the visitor MN and sends one BU message to the RMAP. Similarly, the RMAP send the location information to GMAP and the GMAP in turn sends the information to the HA. The HA sends BACK message, back to the MN via the reverse path of direction of the BU message. AR maintains a list of all visitor MNs under its coverage. When a packet is sent to an visitor MN, it is tunneled to GCoA under which it is located. GCoA then tunnels to the respective RCoA through which the packet can be delivered to MN. This

process is continued and finally MAP delivers the packet to MN through AR. As long as the visitor MN stays within the same internal domain, the HA need not be updated. That means GMAPs makes intra GMAP mobility transparent to HA. Similarly, RMAP makes regional movement transparent to GMAP and MAP makes local mobility transparent to RMAP.

With the network architecture described of Fig. 2, a simulation study is performed to compare the performance of MIPv6, HMIPv6 and TLMIPv6 under various network conditions. Details of the simulation are discussed in the next section.

IV. SIMULATION SETUP FOR COMPARATIVE STUDY

The proposed network architecture of Fig. 2 is implemented in ns-2 as depicted in Fig. 3. There are five domains created in the simulation. The nodes C1(0.0.0) and C2(1.0.0) are CNs and H (3.0.0) is the HA of observed MN (address 3.0.0). Domain 3 is considered as the foreign network with respect to visitor MN. Apart from the visitor MN, domain 3 contains other nodes belongs to its own domain. To make Fig. 3 simple, all nodes in the foreign network are not shown. The Agent class of ns-2 is extended to create a Multi-Layer Agents (MLA) class called MLAAgent::Agent) and attached three nodes in domain 3 to create a three layers model. The GMAP is placed on the node N1, and N2, RMAPs are attached on nodes N21, N22 and N23, MAPs are placed in N31, N32 N33 and N34. The visited MN constructs its Link Care of address using stateless auto configuration method. Six subnets are configured in the simulation area and an AR is placed in each subnet. The ARs are basically the object of Base Station class defined in ns-2 with some additional functionalities added into it. Each AR is attached to one MAP. To study the behavior of HMIPv6, MLA is placed only in node N1 (also in N2) and other MLAs are removed from the simulation architecture.

Fig. 3 Simulation scenario for comparative study of HMIPv6 and TLMIPv6

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TABLE I: SIMULATION PARAMETERS FOR COMPARATIVE STUDY

Parameters Value

Cell coverage range 50m Center to Center distance of cells 90m

MN’s transmission range 100m

WLAN Card Lucent DSSS Card with 802.11 at 914 MHz

MN’s movement pattern Fluid flow model

Traffic Type CBR (Packet size 220 Bytes)

The ARs have been positioned in a way to provide

total coverage to an area of approximately 700x700 square meters considering a transmission range of 50 meters. The MNs move randomly within the coverage area following the fluid flow mobility model. The wireless medium used here is the 2Mbps Wireless LAN 802.11 DCF as provided by ns-2. MN receives data packets from the AR and also sends data to other nodes in the network. For both the situation, the visitor MN has to compete with other MNs to gain access to the channel. The data sent by CNs to MN suffers from delay in the AR queue whereas the data send by visitor MN suffers from delay in the wireless link due to MAC layer characteristics. As our prime intention is to study the performance in receiving the data by the MN due to the mobility of nodes, so we focus on the MNs receiving data from the CNs. Three CNs are configured to send data to visitor MN located in domain 3. One sends elastic traffic (FTP data) which is error sensitive and less delay sensitive, two of them send real time audio data which is less sensitive to error but highly sensitive to delay. An application derived from Application class of ns-2 with a special header to observe the packets sent by mobile node at any intermediate router within some specific situation. An endless FTP sources over TCP as transport protocol is simulated to understand the impact of IP mobility in a three layer model. Although, the simulation scenario models multiple MNs, to make the analysis simple the behavior of a single node is observed in some scenarios. Since all MNs and intermediate elements as well as the network are symmetric, observation of a single MN may be assumed sufficient to analyze the complete scenario.

V. SIMULATION RESULTS The MNs are allowed to move according to fluid flow

mobility model. The movement of MNs is confined in such a varying fraction of MNs allowed to perform global mobility, regional mobility and local mobility. With this scenario, various results computed from the simulation are explained with the help of graphs in the following subsections.

A. Handoff latency During the simulation, out of 50 MNs 10% of MNs

perform global movement, 40% of MNs perform regional movement and 50% MN perform local movement. TABLE II shows a comparison of handoff delay suffered

by a visitor MN in a foreign network in MIPv6, HMIPv6 and TLMIPv6.

TABLE II: HANDOFF LATENCY

Handoff latency (ms)

Protocol Local Regional Global

MIPv6 375.221 375.221 375.221

HMIPv6 355.233 355.233 389.224

TLMIPv6 206.322 219.022 410.422

The data shows that for MIPv6 MN performing all

type of handoff suffers same handoff delay of 375.221 ms. In HMIPv6, MNs performing local and regional handoff suffers delay of 355.233 ms and MN performing global handoff suffers delay of 389.224 ms. On the other hand, for TLMIPv6, MNs suffers 206.322, 219.022, and 410.422 ms delay for local, regional and global handoff respectively. So, TLMIPv6 shows 45%reduced handoff delay over MIPv6 and 41% over HMIPv6 for local handoff. Similarly, for regional handoff the reduction in delay is 41% and 38% over MIPv6 and HMIPv6 respectively. But for globally moving MNs, TLMIPv6 cannot outperform either MIPv6 or HMIPv6. In fact the delay in TLMIPv6 increases by 8% and 5% compared to MIPv6 and HMIPv6 respectively. This increase in delay is due to extra processing carried out in anchor agents of HMIPv6 and TLMIPv6. Despite of this small increased delay for global handoff the TLMIPv6 can be considered better architecture since it gives around 38-41% reduced delay for MN that stay within the same global domain.

B. Signaling cost Signaling cost for all the three architectures are

calculated as the number of bytes injected in the network due to management messages during handoff. In order to compute bandwidth, total number of BU/BACK messages received by each of the anchor agent is counted during the simulation. Fig. 5 shows the binding update cost due to exchange of BU/BACK messages between MN and MAP, MN and RMAP, and MN and GMAP separately for TLMIPv6 architecture. Slow moving MN sends lesser number of BU messages to higher layer anchor agents because it changes its agents less frequently. As soon as speed increases MN changes its anchor agents rapidly, the cost of binding update, also increase.

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Fig. 6 shows the total signaling load in internal network. For TLMIPv6, it is the sum of BU messages received by MAP, RMAP and GMAP during the simulation period. For HMIPv6 it is the numbers of BU messages received by MAP which is located at the border of the domain. For MIPv6 it is the BU messages received by HA. There are twelve hops configured in the in internal network from the AR to border of the backbone. In TLMIPv6, MAP is located at a distance of 3, RMAP at 7 and GMAP at 12 hops from MN. In case of HMIPv6 the MAP is located at a distance of 12 hop count.

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Fig. 6 Signaling load in the internal network

In the internal network, the simulation shows a higher signaling cost in HMIPv6 than the three-layered model. MIPv6 and HMIPv6 have same internal network signaling load. For TLMIPv6, the signaling load is not spread over the entire internal network due to presence of MAP, RMAP and GMAP. On the other hand for MIPv6 and HMIPv6 load in the internal network is spread to router that is located in the boarder of the internal and backbone network. That is the reason of having same signaling load in internal network for both MIPv6 and HMIPv6 architecture.

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Fig. 7 shows the signaling load in the backbone network for TLMIPv6, HMIPv6 and MIPv6. The total number of BU messages received by the HA is calculated during the period of simulation with respect to different MN speed. For both the HMIPv6 and TLMIPv6, cost in the backbone network is same. For MIPv6, backbone signaling load is always higher. The amount of BU in the

backbone network is determined by the number of MNs that leaves the boundary of a GMAP and not by the amount of visitor MNs located in the foreign network. So, the number of layers does not influence much in reducing the signaling load in the backbone network. But in case of MIPv6 all BU messages are injected in the backbone network since there is no intermediate agent to handle movement of BU in internal network.

C. Packet tunneling cost The packet tunneling cost is computed by transmitting

data between CNs to MN in the foreign network. The MN receives initially few packets via HA and then CN is informed about new location of the MN by sending BU messages. Then onwards the visitor MN receives packets without intervention of HA. Every packet communicated to the visitor MN is encapsulated and de-capsulated by the anchor agents. In case of MIPv6 there is no intermediate anchor agent, therefore no such tunneling cost is involved in MIPv6.

The tunneling cost for HMIPv6 and TLMIPv6 are compared in Fig. 8. The data is collected for various numbers of sessions with an average of 50 packets per session using FTP, CBR, Real-time audio, telnet and web application for observation of tunneling cost. The cost increases with the increase in session arrival rate for both the architecture. But in presence of three levels of hierarchy in TLMIPv6 the tunneling overhead is high compared to HMIPv6.

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Fig. 8 Packet tunneling cost

VI. CONCLUSION

A comparative analysis of HMIPv6 and TLMIPv6 is presented in a tabulated form as a summary of the chapter. For slow moving mobile nodes, there is a high probability to stay within the same region for a long time but changing cell to nearby cell under same MAP. In such case HMIPv6 produces larger signaling load and long handoff latency because the mobility management messages has to traverse a long way in the local domain to complete the location update process. In such case TLMIPv6 can out perform HMIPv6. For highly mobile nodes, with a tendency to change the domain frequently, TLMIPv6 can produce extra overhead in the local domain due to existence of intermediate MAPs. But in HMIPv6, this overhead is low as compared to TLMIPv6. In such a case HMIPv6 outperforms TLMIPv6. Table III gives the detailed comparison of both the protocols. The data presented in Table III can help network user to use either

2012 IEEE International Conference on Computational Intelligence and Computing Research

HMIPv6 or TLMIPv6 in a situation there is a choice. In a scenario where users confine their movement within a campus or within a city the TLMIPv6 model is suitable. For users who move internationally neither HMIPv6 nor TLMIPv6 can reduce signaling overhead in the backbone network. For other situations where uses move from one global domain to another, HMIPv6 can be adopted as mobility solution.

TABLE III COMPARISON OF SIGNALING OVERHEAD

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Attributes Supporting Authentication in Point-to-Point Protocol (PPP) and Wireless Local Area Networks (WLAN)”, RFC 3770, May 2004.

[4] S. Deering and R. Hinden, “Internet Protocol Version 6 (IPv6) Specification”, RFC 2460, December 1998

[5] D. Johnson and C. Perkins, “Mobility Support in IPv6”, RFC 3775, June 2004.

[6] H. Soliman and C. Castelluccia, “Hierarchical Mobile IPv6 Mobility Management (HMIPv6)”, RFC 4140, August 2005.

[7] N. Dutta and I. S. Misra, “Mathematical Modeling of Hierarchical Mobile IPv6 Based Network Architecture in Search of Optimal Performance”, Proc. IEEE CS 15th International Conference on ADCOM, pp. 599-601, 2007.

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[10] R. Koodli, “Fast Handovers for Mobile IPv6”, RFC 4068 , July 2005.

[11] J. Rosenberg et. al., “SIP: Session Initiation Protocol”, RFC 3261, June 2002.

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[15] K. Kawano, K. Kinoshita, and Murakami, “Multilevel hierarchical mobility management scheme in complicated structured networks”, Proc. 29th Annual IEEE International Conference on Local Computer Networks, pp. 34- 41, 2004.

[16] S. Saha and A.K. Mukhopadhyay, “THMIP-A Novel Mobility Management Scheme using Fluid Flow Model” , Proc of 2nd National Conference on Emerging Trends and Applications in Computer Science (NCETACS), pp.1-5, March 2011.

[17] Jong-Hyouk Lee, Youn-Hee Han, Sri Gundavelli and Tai-Myoung Chung, “A Comparative Performance Analysis on Hierarchical Mobile IPv6 and Proxy Mobile IPv6”, Telecommunication Systems, vol. 41, pp. 279–292, May 2009.

[18] S. Gundavelli, K. Leung, V. Devarapalli, K. Chowdhury, and B. Patil “Proxy Mobile IPv6”, RFC 5213, Aug 2008

[19] Myung-Kyu Yi, Jin-Woo Choi and Young-Kyu Yang, “A Comparative Analysis on the Signaling Load of Proxy Mobile IPv6 and Hierarchical Mobile IPv6”, Proc 4th International Symposium on Wireless Pervasive Computing, pp. 1-5, 2009.

[20] W. Richard Stevens, Bill Fenner and Andrew M. Rudoff, UNIX Network Programming Volume 1, Addison-Wesley Professional, USA, 2003.

[21] The Sockets Networking API - Third EditionBerkeley sockets-Wikipedia, the free encyclopedia from http://en.wikipedia.org/wiki/ Berkeley_sockets.

[22] Jonathan B. Postel, “Simple Mail Transfer Protocol”, RFC 821, August 1982.

[23] J. Myers and M. Rose, “Post Office Protocol Version 3”, RFC 1939, May 1996.

[24] S. Pack, B. Lee, and Y. Choi, “Proactive Load Control Scheme at Mobility Anchor Point in Hierarchical Mobile IPv6 Networks”, IEICE Trans. Inf. & Syst., vol. E87-D(12), pp. 2578–2585, December 2004.

[25] R. Wakikawa et al, “Enhanced Mobile Network Protocol for its Robustness and Policy Based Routing”, IEICE Trans. Commun., vol. E87-B(3), pp.445–452, March 2004.

[26] Albert Cabello.s-Aparicio et. al. “Measurement Based Analysis of the Handover in a WLAN MIPv6 Scenario”, Passive and Active Network Measurement, Lecture Notes in Computer Science, vol. 3431, pp.203-214, 2005.

[27] Shariq Haseeb and Ahmad Faris Ismail, “Comparative Performance Analysis of Mobile IPv6 Protocols”, Special Reference to Simultaneous Bindings Journal of Computer Sciences, vol.2(2), pp.154-159, 2006.

[28] R. Hsieh,A. Seneviratne, H. Soliman and K. El-Malki, “Performance Analysis on Hierarchical Mobile IPv6 with Fast-handoff over End-to-End TCP”, Proc. of IEEE Global Telecommunications Conference (GLOBECOM), 2002.

Speed Hops

Traffic in local network

Remarks HMIPv6

TLMIPv6

Local Regional Domain

Low Low Too High High Low Low TLMIPv6

Low High High High Moderate Moderate TLMIPv6

High Low High High Moderate Moderate TLMIPv6

High High Low High High Moderate HMIPv6

2012 IEEE International Conference on Computational Intelligence and Computing Research