A Major Functionality in Next Generation Networks Using -- Mobility Management

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1 A Major Functionality in Next Generation Networks Using -- Mobility Management Sunil kumar J, Satyanarayana Gadadda, K.Sateesh Kumar Assistant Professor, Department of Electrical and computer science Engineering, Adama Science and Technology University, Adama- Ethiopia Associate Professor, Department of Computing, Adama Science and Technology Univerisity,Adama- Ethiopia Assistant Professor, Department of Computing, Debre berhab University, Ethiopia Abstract Next Generation Networks have a major impact on existing communication technology. The main goal of Next Generation Networks is to give a greater flexibility to the users to access the desired services from the available heterogeneous networks at anytime, anywhere vigorously. It allows the convergence of multiple applications to run on the same network; consist of voice, data and video and other new media applications. To achieve seamless mobility in heterogeneous network environments, Mobility Management is providing handover control functions and location updating operations. This paper reviews on the importance of Mobility Management functionality, its types and operations for Next Generation Networks. This paper also discusses about proposed handover control schemes aimed at global and localized mobility management by classifying them according to host or network based mode. Keywords Next Generation Networks, Mobility Management, Handover Control Schemes, Location Management, Mobility Management Protocols, Types of Mobility Management. 1. INTRODUCTION A Next Generation Network (NGN) is the term given to describe a telecommunication packet-based network that handles multiple types of traffic. In NGN the user can have unfetter access to different type of networks or type of services on their choice. The user or mobile entities can communicate/access data and services which are not depending on location of mobile and type of network called generalized mobility, supported by NGN.In NGN environment, mobility management provides variety of functions and control operations which could benefit the user from the continuation of the services in a seamless manner, while it moves around the various access technologies. Seamless mobility can be achieved by handover control functions which provide various handover schemes also called as Mobility Management Protocols. The rest of the paper is organized as follows, section 2 narrates about the NGN environment, its characteristics and capabilities and key areas of importance for NGN. Section 3 focuses on mobility management, its classification based on movement of mobile terminal. This section also classifies types of mobility management in NGN. Section 4 describes about the major functionalities of mobility management its control functions and operations that support for mobility. This section also presents the handover control schemes classifying by host based and network based modes aiming at global and localized mobility that are proposed for seamless handover. Section 5 concludes that the proposed mobility management protocols helps in providing smooth and fast handover. This section also enlightens the importance of handover control schemes and location management control functions and operations for seamless mobility in NGN. 2. NGN ENVIRONMENT A Next Generation Network (NGN) is a packet based network able to provide telecommunication services and able to make use of multiple broadband. It supports generalized mobility which will allow consistent and ubiquitous provision of services to users. Generalized mobility means the ability for the user or other mobile entities to communicate and access services irrespective of changes of the location or technical environment. NGN is conceived as a concrete implementation of the Global Information Infrastructure (GII). ITU-T recommendations Y.2001 (General overview of NGN) in the Y series provide the foundation of the NGN. The target of NGN is to ensure that all elements Copyright to IJAREEIE

2 required for interoperability and network capabilities support applications globally across the NGN while maintaining the concept of separation between transport, services and applications [1]. Figure 1 shows the NGN environment where we can see the core NGN and access NGN and how they are connected. A. Characteristics of NGN The NGN can be defined by the following fundamental characteristics: Packet-based transfer; decoupling of service provision from transport, and provision of open interfaces; support for wide range of services, applications and mechanisms based on service building blocks; separation of control functions among bearer capabilities; generalized mobility; unrestricted access by users to different service providers; broadband capabilities with end-to-end Quality of service [2]. Figure 1 Network Environment of NGN B. Capabilities of NGN The following are some of the major expected capabilities of NGN: NGN shall provide the capabilities to make the creation, deployment and management of all kinds of services possible; NGN should be comprised of service related APIs in order to support the creation, provisioning and management of services; NGN separates services and transport, allowing them to be offered separately and to evolve independently; a major feature of NGN will be generalized mobility, which will allows consistent provision of services to user, a unique entity when utilizing different access technologies, regardless of their types [1][2]. C. Areas of Key importance of NGN The following are some of the areas of key importance in the provision of NGN: Quality of Service and performance; Network management; Security; and Generalized mobility. Generalized mobility means providing the ability of using different access technologies, at different locations while the user and/or the terminal equipment itself may be in movement allowing users to use and manage consistently their applications/customer services across existing network boundaries [1][2][5].At present mobility is used in a limited sense such as movement of user and terminal and with or without service continuity to similar public accessed networks such as Wi-Fi, WiMAX, HSPA, UMTS, etc. and service discontinuity to some wired line accessed networks with strong limitations. In the future, mobility will be offered in a broader sense where users may have the ability to use more access technologies, allowing movement between public wired access points and public wireless access points of various technologies. This means that this movement will not necessarily force an interruption of an application in use or a customer service. Generalized mobility requires significant evolutions of current network architectures. Enabling more transparent fixed wireless broadband communications and mobility across various access technologies appears as a major issue. 3. MOBILITY MANAGEMENT IN NGN The term Mobility Management (MM) describes about functionalities of mobile including authentication, authorization, location updating and handover schemes used for mobility. Mobility defines about the ability of the user or mobile terminals to communicate and access services independent in changes done in location or the technical environment. MM is an essential requirement for NGN users to communicate anytime and from anywhere. This could be facilitated through the use of various wired or wireless access technologies to enable users to communicate over heterogeneous network environments. Mobility management can be classified as follows according to what moves: First is Terminal mobility, in which the mobile terminal equipment is moving and accessing multimedia services from different locations and while in motion. Second, Network mobility, where a set of fixed or mobile terminals are networked, that entire network changes its point Copyright to IJAREEIE

3 of attachment or moving itself. Third, service mobility can be applied for mobility of a particular service irrespective of the location of the mobile terminal that is used. Fourth, Personal mobility is the ability of a user to access multimedia services at any mobile terminal providing personal identification information and the network also may provide those services that the user is eligible for[3][4]. This paper focuses on terminal mobility as the manor part of mobility in applying MM related functionalities of NGN. In addition to the above classification handover is also divided into two types as: horizontal handover; vertical handover. In horizontal handover, the mobility is considered in the same protocol layers and uses same access technology for handover. Whereas in vertical handover, the mobile terminal changes its type of access technology and chooses a supporting infrastructure that provides mobility. For example, a suitably equipped laptop might be able to use both a high speed wireless LAN and a cellular technology for Internet access. Thus the laptop user might want to use a wireless LAN connection whenever one is available, and to 'fall over' to a cellular connection when the wireless LAN is unavailable [21]. Types of MM in NGN The types of mobility management of NGN can be classified into 5 scenarios, considering only terminal mobility as the major category [3] [5]. Figure 2 MM within AN Figure 3 MM in same ANs, within CN Scenario 1: MM within AN As shown below, in Figure 2, the mobile terminal is moving within the access network, without changing its technology with same core network is considered as scenario 1, results in existing issues. Scenario 2: MM in same ANs, within CN In scenario 2, the mobile terminal is moving from one Access Network to another of same type results in horizontal handover shown in Figure 3. In this case the mobility management should handle the issues on applying horizontal handover schemes like Mobile IPv6 and Hierarchical Mobile IPv6 [6]. Scenario 3: MM in different ANs, within CN Figure 4 is considered as scenario 3 in which the mobile terminal is moving from one Access Network to another of different type results in vertical handover. Issues related to this scenario can be handled by Media Independent Handover (MIH) developed and introduced by IEEE work group [18]. Figure 4 MM in different ANs, within CN Figure 5 MM with same AN, different CNs Scenario 4: MM with same AN, different CNs In scenario 4, the mobile terminal handover across different core networks but may be with the same type of access network results in the issues related to network-to-network interfaces like authorization of user, service level agreement Copyright to IJAREEIE

4 (SLA) negotiation etc., rather than change in technology. This scenario belongs to horizontal handover as shown in Figure 5. Figure 6 MM in different ANs, different CNs Scenario 5: MM in different ANs, different CNs Figure 6 is considered as scenario 5 the mobile terminal is moving in different ANs and different CNs consolidates in vertical handover in different core networks including both issues handled by vertical handover schemes and administrative services like authorization of user, service level agreements as in scenario 3 and 4. The above scenarios differentiate and summarize the requirements for mobility management in NGN as shown in the following table Table 1 [4]. Administration services Type of Service handover User Level (horizontal authorizatio Agreemen / n ts (SLA) vertical) Within AN None None None Same ANs, within CN Same Same Horizontal Different ANs, within CN Same Same Vertical Within same AN, Same Same Horizontal different CNs Different ANs, different CNs Different Different Vertical Table 1 Requirements for mobility management in NGN 4. FUNCTIONALITIES OF MOBILITY MANAGEMENT The major functionalities that are required for support of mobility are: Location Management and Handover Control [7][8]. A. Location Management The responsibilities of location management are based on the mode of mobility. Network-based mobility means the base station/ access points take initiation of registering the mobile terminal. In this mode the responsibilities are updating mobile information between adjacent base station/access points and binding operations between mobile terminals with new registration. Host-based mobility means the mobile terminal itself takes active role in registration, updating and binding operations rather than network. In non-roaming case, the mobility is happened within the home NGN, so the location updating is done within the NGN for both host-based and network-based modes. Whereas in roaming case, the mobile terminal is moving from home NGN to visited NGN results in location updating. This can be done between the service providers in considerations of authentications, authorizations and SLA. This case is described in scenario 4 and 5. Registration and update functions: The location registration and update functions are used to keep track of the current location of a mobile terminal. When a mobile terminal is attached to the network, it will register its current location with the location database for Location Management. When the mobile terminal moves into the other network, Copyright to IJAREEIE

5 the corresponding update function will be performed and the location information is updated both at home network and visited network [7]. Query and response functions: The location query and response functions are used to locate the mobile terminal. The information of the current location of the mobile terminal will be identified through the suitable location query and response operations. It is noted that the location query and response operations may be performed together with a relevant service control function [7]. B. Handover control In providing seamless mobility or session continuity, the handover control functions will be performed to minimize the data loss and handover latency during the handover of the mobile terminal. The handover control schemes are based on the protocol layers. This paper focuses on the schemes that can be implemented in L3, Network layer. These schemes are stated as mobility management protocols which are again classified based on the mode of mobility. MIPv6 (Mobility support in Internet Protocol version 6) and HMIPv6 (Hierarchical MIPv6) are host based mobility protocols. Along with it, two other protocols, FMIPv6 (Fast MIPv6) and F-HMIPv6 (Fast handover for Hierarchical MIPv6) are also mentioned as host based mobility protocols. In network based mobility PMIPv6 is considered as the mobility management protocol [6] [9]. Global Mobility Management Protocol is one that maintains session continuity when a mobile terminal moves from one network to another causing change in its network topology [11]. The above said MIPv6 is Global Mobility Management Protocol as it maintains session continuity. Other than MIPv6 mobility protocols like HIP (Host Identity Protocol) [12] and IKEv2 Mobility & Multihoming (MOBIKE) [13] are also considered as Global Mobility Management Protocols. Location privacy is a problem exists in global mobility protocol can be solved using a localized mobility management protocol called Network - based Localized Mobility Management (NETLMM) [22]. MIPv6: MIPv6 is defined by RFC3775 [19] as Mobility support in IPv6 using IPSec to Protect Mobile IPv6 signaling between mobile nodes and home agents as quoted in RFC3376 [20]. The main goal of MIPv6 is to give IP connectivity through static IP address for mobile terminals even at session continuity between different L2 technologies. In this scheme a Mobile terminal (MT) moves to another network. Once movement is detected, it is followed by a tie up with an agent in the visited network known as the visited agent (VA) and acquiring of a new IP address known as the Careof-Address (CoA). The VA not only helps the MT to inform it s Home Agent (HA) about its new location, it also serves as an intermediary by accepting packets from HA and forwarding them to MT. The entity or node communicating with the MN is known as the Correspondent Terminal (CT). The reply to the CT is send directly from the MT, which leads to triangular routing [10] [14]. HMIPv6: Hierarchical Mobile IPv6 introduces a new node known as Mobility Anchor Point (MAP). MAP can be present anywhere in the hierarchy of routers including access routers belonging to the access networks. MT interacts with the MAP instead of the HA which might be lower down in the hierarchy of routers. MAP can be closer to the MT than a HA giving it an advantage over MIPv6. HMIPv6 operations are classified into four stages, MAP discovery, MAP selection, Movement Detection and Binding Updates. MAP selection is done by the MT through the user of Router advertisements, with a hierarchy of MAPs choosing the highest MAP preference and preference is reduced by one as the MT chooses to use a particular MAP [15]. FMIPv6: During the process of handover, there is a time period during which the MT is unable to send or receive any packets. FMIPv6 precisely aims at reducing handover latency. It is based on the idea that the MT is aware of the IPv6 subnet it is going to move to before the actual movement takes place. The access router in the foreign network can buffer all the packets destined for the MT that arrive till it actually gets connected after handover. MT home network address is previous CoA (PCoA) and the connected router is Previous Access Router (PAR). When it moves to new network its new router is called as New Access Router (NAR) acquires new CoA (NCoA). Fast handover consists of three steps: Handover Initiation, tunnel establishment and packet forwarding [17]. A tunnel between the PCoA and NCoA is created when a PAR sends a Handover Initiation message to NAR and remains active until the MT completes the Binding update with its correspondents. PMIPv6: Network based mobility protocols aim to keep the MN unaware of the process of mobility. If the MT is part of the mobility management, there is the burden of deployment and implementation on the host (MT). To reduce the onus from the MT new protocols are being introduced to shift the burden of mobility management to the network only. Such methods are more in focus as they give host the liberty to select a protocol of its choice and also bring more MTs within the mobility circle. NETLMM (Network Based Localized Mobility Management) defines an access network with a Mobile Access Gateway (MAG) and a Localized Mobility Anchor (LMA), router just like the HA in MIPv6 that maintains a collection of host routes and associated forwarding information for MT s falling under its domain. PMIPv6 is a network based mobility management protocol standard where MT involvement is removed completely by involving a network node (MAG) and a HA (LMA) in the signalling process creating a Proxy Mobile IPv6 Domain [16]. Copyright to IJAREEIE

6 5. CONCLUSIONS AND FUTURE WORK NGN is a platform able to provide telecommunication services like voice, data and video services irrespective of the network technologies and uses multiple broadband. In supporting generalized mobility, mobility management providing a variety of control functions and operations in location finding and handover control. Developing efficient Mobility management protocols help NGN in providing seamless handover. Enhancements in location management control functions and operations lead to effective mobile detection and fast handover. REFERENCES [1] ITU-T Recommendation Y.2001 (12/2004) General overview of NGN. [2] Robert Wojcik, Architecture of NGN by ITU T, AGH University of Science and Technology, 21 st January 2009, Poland. [3] ITU-T Recommendation Y.2018 (09/2009) Mobility management and control framework and Architecture within NGN Transport stratum. [4] ITU-T Recommendation Y.2801 (11/2006) Mobility management requirements for NGN. [5] ITU-T Recommendation Y.2804 (02/2008) Generic framework of Mobility management for Next Generation Networks. [6] Shaima Qureshi, M. Ashan Chishti and Ajaz H. Mir, Mobility Management in Next Generation Networks analysis of handover in host and network based mobility protocols, International Conference on Communications and Information Technology (ICCIT), vol., no., pp , Mar [7] ITU-T Recommendation Y.2805 (10/2008) Framework of location management for Next Generation Networks. [8] ITU-T Recommendation Y.2806 (10/2008) Framework of handover control for Next Generation Networks. [9] Holger Zuleger, Mobile IPv6 a short introduction, Wireless Communications, Networking and Mobile Computing (WiCom) 2007, International Conference, vol., no., pp , Sept [10] Mobile IPv6 an article from Wikipedia, the free encyclopedia, [11] J.Kempf, Ed., "Problem Statement for Network- (NETLMM)," IETF Request for Comments 4830, April [12] R. Moskowitz and P.Nikander, "Host Identity Protocol (HIP) Architecture," IETF Request for Comments 4423, May International Conference on Internet Technologies & Applications (ITA 09), UK, September [13] X.Pérez-Costa, M.Torrent-Moreno and H.Hartenstein, A Simulation Study on the Performance of Hierarchical Mobile IPv6, In Proceedings of the International Teletraffic Congress (ITC), Berlin, Germany, August [14] S. Gundavelli, Ed.,V. Devarapalli,K. Chowdhury, B.Patil, "Proxy Mobile IPv6", IETF Request for Comments 5213, August [15] Udugama, A.; Iqbal, M.U.; Toseef, U.; Goerg, C.; Changpeng Fan; Schlaeger, M.;, "Evaluation of a Network Based Mobility Management Protocol: PMIPv6," Vehicular Technology Conference, VTC Spring IEEE 69th, vol., no., pp.1-5, April [16] Esa Piri and Kostas Pentikousis, IEEE , the International Protocol Journal, Volume 12, No.2, June [17] D. Johnson, C. Perkins and J. Arkko, Mobility support in IPv6, IETF Request for Comments, June [18] J. Arkko, V. Devarapalli and F. Dupont, Using IPSec to Protect Mobile IPv6 Signalling between Mobile nodes and Home agents IETF Request for Comments, June [19] Vertical Handover an article from Wikipedia, the free encyclopedia, [20] C. Vogt, J. Arkko, A Taxonomy and Analysis of Enhancements to Mobile IPv6 Route Optimization, Request for Comments: 4651, February BIOGRAPHY Mr.Sunil kumar.j was born in Tirupathi, India. He received his B.Tech in Department of Electrical and Electronics from Anna Univeristy, Chennai, in 2006 and M.Tech from Sri Venkateswar University, Tirupathi, in Currently working as a Assistant Professor in Adama science and technology university, Adama. His research interests include Power Systems, Renewable Energy, Fuzzy Logic, Neural Networks, Flexible AC Transmission System (FACTS).Up to now 8 International journals are in credit, 6 International conferences. He is working as a reviewer for many journals like International Journal of Electrical Power & Energy Systems(Elesvier), International Journal of Scientific and Engineering Research, (IJ-ETA-ETS), Global Journal of Researches in Engineering, United States, International Journals of Engineering & Sciences. Dr. Satyanarayana Gaddada received his Bachelor s Degree in Science from JVR Govt Degree College, Sathupally, Khammam, AP, India. He received his MCA, KMPGC, Khammam, AP, India and He is a Doctorate holder in Computer Science &Engineering with specilization in Data Warehousing and Data Mining. With13+ years of teaching experience, currently he is Associate Professor, Department of Computing, Schoolof Engineering, Adama Science and Technology University, Adama, Ethiopia. He is a lifemember of(lm53294) Indian Society for Technical Education of India. Copyright to IJAREEIE

7 KongaSathishKumar,received his Bachelor s Degree incomputer Science from Chaitanya Degree College, Hanamakonda, Warangal, AP, India. He received his M.Sc.(CS) from ALN Raju Memorial College, Warangal, AP, India. With 12+ years of teaching experience, currently he is Assistant Professor, Department of Computing, DebreBerhan University, Debre Berhan, Ethiopia. Copyright to IJAREEIE