Mobility Management Framework, Issues and Challenges

Transcription

1 Mobility Management Framework, Issues and Challenges Roopali Sood 1, Atul Garg 2 1 Research Scholar, 2 Associate Professor M.M. Institute of Computer Technology & Business Management Maharishi Markandeshwar University, Mullana, Ambala, Haryana Abstract Technology is advancing at a faster pace and need for internet services anytime anywhere is required. To make this vision of all time better services available to a customer, efficient mobility handling methods must be devised. Two main schemes to implement mobility management are: Handoff and location management.in current paper various issues related to mobility management in the coming generation of networks are highlighted and also throws light on the problematic areas to ensure efficient mobility handling. Keywords: Mobility Management, Location Management, Handoff, mobility models, mobile node. 1. Introduction Millions of Terminals are connected through Internet across the globe with a common goal of being connected 24 by 7, irrespective of the location and time. This has lead to growth in all fields, commercial, educational, transportation etc. As the Network Technologies are rapidly moving on the growth track, different access management techniques are being proposed to meet the challenges of seamless connectivity. The management of these networks is prime aspect as theses networks involve high resource sharing. The Fig. 1 depicts the heterogeneous setup of networks and the connectivity amongst those, through mobility management framework [1& 2]. Fig. 1: Mobility in Heterogeneous Network The vision of future network technology lies in provisioning a comprehensive all IP based solution which facilitates voice, data and streamed multimedia services [3]. The generic protocols do provide the interconnection among all wireless and wired existing technologies, but with high usage of multimedia application the current protocols do not perform at the required level of performance and rendering desired quality. Thus new mobility protocols are being designed for better performance taking into consideration the new generation of networks. 2. Related Work This section encompasses the related work done by the various renowned researchers. An extensive study starting from Quality of Service (QoS), mobility management and handover management has been carried out. Techniques addressing the issues prevailing in mentioned fields have been explored. The authors in [4] described the multihoming feature of SCTP but its inefficiency in supporting moving nodes hence discussed msctp which enables the transport layer mobility. Explained Cross-Layer Route Method in SCTP with MIPv6 has been through simulation. Modified the original Binding Update procedure and added the interfaces between the MIPv6 and SCTP for the cross-layer management. Researchers in [8] proposed a novel quality-aware adaptive Concurrent Multipath Transfer solution (CMT-QA) that utilizes SCTP for FTP-like data transmission and real-time video delivery in wireless heterogeneous networks. CMT-QA monitors and analyses regularly each path s data handling capability and makes data delivery adaptation decisions to select the qualified paths for concurrent data transfer. Volume 3, Issue 3, March 2014 Page 513

2 The authors in [9] proposed an enhanced FPMIPv6 technique for improving the VHO (vertical handover) operation by using shorter data-paths and improved coordination of buffered packet-forwarding and TN switching, which results in a significantly reduced packet-delay. Researcher in [3] explained address specific research issues and solutions on different aspects of 4G wireless systems and beyond. This special issue demonstrates research outcomes in different aspects of 4G wireless, like scheduling, resource allocation, cognitive and cooperative communications, multicast services and coverage and planning of small cells. The researchers [10] have established a route by on demand routing technique in which many features like the energy of the node, location, bandwidth of the packet are analysed. So, when the packets need to be sent, it analyses all the features and establishes the route with the efficient node that has one hop count by using the SCTP transport protocol. On transmitting the packets some energy from the node gets reduced hence there is a high chance of congestion, since the capacity of the node is reduced. Thus the packet loss rate and end-to-end delay is reduced and QOS is increased in the system by use of SCTP. The authors in [11] investigated state-of-the-art multihoming techniques using Stream Control Transmission Protocol (SCTP). A comprehensive survey of developments has brought forth three main research areas, namely: handover management, Concurrent Multipath Transfer (CMT), and cross-layer activities. The authors of [12] highlighted various issues and challenges related to mobility management in 4G - networks. Discussed the issues pertaining to the design of handoff management i.e signaling overhead, QoS, power requirement, scalability, reliability and robustness. The researchers in [13] reviewed recent developments in location management.survey of various methods for handoff management between heterogeneous systems has been presented. Discussed methods for inter-system handoffs in packetswitched networks according to the protocol layer in which the handoffs takes place. Presented open problems for mobility management in future wireless networks. 3. Mobility Management Mobility Management deals with tracking subscriber s location, routing, authorization, and authentication and handling handoffs. Mobility between the mobile terminals is studied into two main types: 1. Intra-system (intra-domain) 2. Inter-system (inter-domain) Intra-system mobility is the movement of the mobile terminals between the cells of the same network. It can also be refered as Horizontal handoff. Intra-system mobility management techniques are based on similar network interfaces and protocols. Inter-system roaming refers to moving between different networks which differ in standards and technology. Mobility management in wireless networks is handled by its two main strategies: location management and handoff management [6]. Location Management is related to locating and tracking the location and movement of a mobile node and updating the mobile terminals location information using the database entities HLR (Home Location Registration) and VLR (Visited Location Registration) while Handoff Management focuses on transfer of the link from one base station to another during the movement of the mobile node to maintain data continuity. So when we talk about the issues and challenges related to mobility management then it is required to consider both these strategies and the issues must be explored. Issues in location management is not related to routing and thus is not protocol dependent, while handoff algorithms require routing and resource management and are dependent on network protocols.the following figure depicts modules involved in mobility management [5] Fig. 2 Mobility Management 3.1 Location Management Location management enables the system to track the locations of Mobile Node (MN) during its course of movement at various networks. It includes two major tasks. The first is location registration (updation), where the MN informs the Volume 3, Issue 3, March 2014 Page 514

3 system at regular intervals, to update relevant location databases with its current location information. The second is call delivery, where the system determines the current location of the MN based on the information available at the system databases when a communication for the MN is initiated. Two major steps are involved in call delivery: determining the serving database of the called MN and locating the visiting cell/subnet of the called MN.[14] The latter is also called paging, where polling messages are forwarded to all the cells/subnets residing in registration area of the called MT. For intersystem roaming, the design of location management techniques has the following challenges: Improving Quality of Service by Reducing Signals: Latency is the most important parameter considered by the researchers because to reduce latency is the peak requirement. It is required to deliver services and update location of the MN with least delay. Signaling overhead is the number of access to the related databases which must be lowered. Hence, the new research can be originated and new methods can be proposed to lower the complexity of location updating and registration process. Control on overlapping for Heterogeneous Networks:-When a MN enters into the overlapping region then it becomes difficult to decide that with which network MN must perform registration. Sometimes wrong registration may lead to more latency and increases overhead. 3.2 Handoff Handoff/Handover is a process of switching from one area of coverage or cell to another area of coverage or cell in case of weakening of a call in current state. A handoff process occurs when a mobile user moves beyond the radio coverage of its access points to another [2]. During this, some latency is due to which the user is unable to send or receive traffic for few seconds even there are many neighboring access points in a wireless environment.therefore handoff mechanisms are to be employed in such a way that they can choose the best and optimal access point to enjoy continuous services [3]. Hence different approaches are proposed and researches are being done to achieve better handoff services. Even researchers use fuzzy logic and neural networks to choose the best AP or base station. With the advent of new networks technologies and growth in the mobile communication following are few prominent issues that need attention for an efficient handoff. Handling of Inter domain and intra domain communication: In the modern era it is important to analyze the performance of a protocol so that it can be well distinguished that which protocol can work better in intra domain and inter-domain environment. Fast and seamless handoff required: It is required that handoff must be quick when required to provide continuation of services otherwise it may result in packet loss and call dropping or blocking. Need for routing efficiency: Since handoff is dependent on the protocols so relevant protocols must be preferred to remove problems such as routing delay, triangular routing problem, etc. e.g. MIP has provided a route optimization technique by eliminating triangular routing problem. Improved QoS: Many new methods are being proposed to deliver Quality of Service (QoS) but some problems are routed in wireless technology which hinder in its performance. Some of these issues are restricted bandwidth, low reliability and delay. Security provision: the mobility scheme should support different levels of security requirements such as data encryption, decryption and user authentication during registration [5]. Mobility between access technologies: requires an access technology that offers high bandwidth with low delay, less packet loss and high security. But it is challenging to fulfill all these requirements together so a customer has to maintain a service priority and accordingly choose the access technology [6]. Optimization of protocol parameters: Some approach like Fuzzy logic can be applied For parameter optimization and more and more attributes contributing to network performance need to be explored [7]. Cross Layer Optimization: There must be proper co-ordination between the network layer and the Datalink layer for handoff process. New methods being proposed must focus on how to establish proper cooperation between different layers, to study the level of cooperation and how much information is being exchanged between different layers [4]. 4. Mobility Management models and components involved 4.1) General mobility management model i. Mobile node and Corresponding node Mobile node- freely roaming node which can change its point of attachment from one node to another, Corresponding node: it can be either mobile or stationary helps in correspondence between the mobile node and home network. ii. Home network and foreign network Home network originally assigns IP address to the mobile node and to which the mobile node is always communicating. Foreign network to which the mobile node is currently attached during its course of movement. The foreign network communicates with the mobile node through a temporary Care of Address (CoA). Volume 3, Issue 3, March 2014 Page 515

4 iii. Home address and Care of Address (CoA) Home address is permanent unchangeable address assigned to mobile node through its home network. CoA dynamically assigned address assigned to Mobile node by the foreign network till the period node resides in the foreign network. iv. Home mobility agent and foreign mobility agent Home mobility agent helps in attachment of mobile node when it moves to foreign network. Foreign mobility agent: it s a router on the foreign network which helps in accessing internet and thereby receiving datagrams delivered to CoA. The following figure shows the basic component involved in general mobility framework as discussed in [5]. 4.2) Hierarchical mobility management model: It introduces the domain based mobility concept which gives a better control over mobility in terms of performance and flexibility specifically for the nodes which are frequently moving. Fig. 4 explains the broader point of segregation between macro and micro mobility schemes [5]. Fig.4: Hierarchical Mobility Management Features Fig.5: Hierarchical Mobility Management Framework Domain refers to a collective term i.e collection of networks administered by a common administrator and comprising of one or more foreign networks. Fig. 5 reveals the concept of domain (inter and intra domain communication) [5].Various schemes have been proposed for Macro and Micro mobility. 5. Proposed Work Looking at the immense growth in the digital and handheld devices, services being offered and the mobility patterns, the discussed issues and challenges indicate the need for study and exploration of more parameters which can be considered and incorporated in existing mobility framework so that the user get better QoS. Hence, cross layer coordination need to be worked in future, so that depending upon the domain, the respective layer can contribute in mobility management. Volume 3, Issue 3, March 2014 Page 516

5 6. Conclusion As more and more services are being offered to the users over mobile networks. The user expectation has turned to be more demanding and priority centric. This paper in brief discusses the critical areas in field of mobility management in wireless networks. No doubt many researchers are finding their interest in this area but still many issues still exist and these issues are due to problems which are routed in wireless technology i.e bandwidth, reliability, latency and delay. But as we are drifting towards 4g and higher generations, heterogeneous networks can put an end to these problems by offering high coverage, data rates and bandwidth. Thus efficient mobility framework need to be developed which is more adaptive, intelligent and service centered. References [1] David Ott,Shilpa Talwar, Intel Labs,University Research Office, Exploring Next Generation Wireless (5G): Transforming the user Experience, [2] 5G : A Technology Vision, [3] Saxena, Navrati,A Sengupta, Shamik, A Wong, Kai-Kit,A Roy, Abhishek, Special issue on advances in 4G wireless and beyond, in Springer-EURASIP Journal on wireless communication and Networking [4] Hongbo Shi and Tomoki Hamagami Cross-Layer Routing Method for the SCTP with Multihoming MIPv6, LNICST 37, pp , [5] Junzhao Sun ; Douglas P. Howie and Jaakko J. Sauvola "Mobility management techniques for the next-generation wireless networks", Proc. SPIE 4586, Wireless and Mobile Communications, [6] Frederic Paint, Paal Engelstad, Erik Vanem, Thomas Haslestad, Anne Mari Nordvik, Kjell,Myksvoll, Stein Svaet, Mobility Aspects in 4G Networks, White paper,2002. [7] Zhongwei Zhang and Lu Jineprints Improving the Performance of SCTP Transport Protocol [8] over Wireless Networks,.University of Southern Queensland,usq.edu.au/1750/1/68.pdf,2013 [9] Xu, Changqiao, Liu, Tianjiao, Guan, Jianfeng, Zhang, Hongke, Muntean, Gabriel-Miro, "CMT-QA: Quality-Aware Adaptive Concurrent Multipath Data Transfer in Heterogeneous Wireless Networks", IEEE Transactions on Mobile Computing, vol.12, no.11, pp , [10] Johann Márquez-Barja, Carlos T. Calafate, Juan-Carlos Cano, Pietro Manzon, An overview of vertical handover techniques: Algorithms, protocols and tools, Journal Computer Communications archive Vol. 34 Issue 8, Pages , [11] K. Manikandan & M. A. Saleem Durai, Optimised layered approach on congestion control with efficient energy and QOS improvement for wireless network, in Elixir Comp. Sci. & Eng , [12] Wallace, T.D. & Shami, A., A Review of Multihoming Issues Using the Stream Control Transmission Protocol", Communications Surveys & Tutorials, IEEE, vol.14, no.2, pp , [13] P Payaswini, D. H Manjaiah, Challenges and issues in 4G Networks Mobility Management, International Journal of Computer Trends and Technology (IJCTT) volume 4 Issue 5, 2013 [14] Yu, F. R., Wong, V. W. S., Song, J.-H., Leung, V. C. M. and Chan, H. C. B. (2011), Next generation mobility management: an introduction. Wirel. Commun. Mob. Comput., pp ,2011. [15] J. Sen, "Mobility and Handoff Management in Wireless Networks," Arxiv preprint arxiv: , [16] P.Dhand, Sumit Mittal, Handoff Algorithms based on RSSI and Fuzzy Approach: A Survey, International [17] Journal of Application or Innovation in Engineering & Management (IJAIEM), Vol. 3, No. 2, pp ,2014. AUTHOR Roopali Sood received degree of Master of Computer Management from Devi Ahilya Vishwavidyalaya Indore (M.P), India in Presently pursuing Ph. D from Maharihi Markandeshwar University, Mullana, (Ambala). She is Student Member of Delhi section of IEEE, International Association of Engineers. Her area of interest is mobile networks and mobility related issues in coming generation networks. Atul Garg received degree of Master of Computer Applications from Kurukshetra University, Kurukshetra in 2004 and completed his Ph. D degree from Maharishi Markandeshwar University, Mullana (Ambala) in Currently, he is working as an Associate Professor at M. M. I. C. T. & B. M., Maharishi Markandeshwar University, Mullana (Ambala), Haryana. He is Senior Member of the association of Universal Association of Computer & Electronics Engineers (UACEE), Australia, Member in the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering (ICST), Belgium and Member in the International Association of Engineers, Hong Kong. His area of interest is web, Query Optimizations and mobile ad hoc networks. Volume 3, Issue 3, March 2014 Page 517