A Survey on Uplink Bandwidth Request in WiMaX Networks

Document Sample
A Survey on Uplink Bandwidth Request in WiMaX Networks Powered By Docstoc
					   International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012                                          ISSN 2278-6856

     A Survey on Uplink Bandwidth Request in
                WiMaX Networks
                                          Reka.R1 and Dr.R.S.D.Wahidabanu2
                             Research Scholar, Anna University of Technology, Coimbatore, India.
                                Principal, Government College of Engineering, Salem, India.

Abstract: The bandwidth allocation in both wired and
wireless networks has posed great challenges to network
engineers for improving desirable Quality of Service (QoS).
Bandwidth allocation is always an important element for
improve QoS of network. Bandwidth utilization is considered
optimum when there is no over- or under-allocation of
capacity for a particular service type. Despite this, IEEE
802.16e-2005 does not have a bandwidth allocation algorithm
or mechanism to support (Worldwide Interoperability for
Microwave Access) WiMAX network presently. This includes
both uplink (UL) and downlink (DL) directions. Thus, most of
researches are focusing this area. In order to improve the
QoS of WiMAX demand, the total capacity of WiMAX system
must be optimized. In this review, we focus on scheduling
algorithms for the uplink traffic in WiMAX networks.                       Figure 1: WiMAX Network Infrastructure
Keywords: WiMAX, QoS, UpLink (UL), DownLink
                                                                     1.1 Fixed WiMAX
(DL), Bandwidth Allocation Scheduling.

The IEEE 802.16 standard, commonly known as WiMAX
is one of the most popular BWA technologies today,
which aims to provide high speed broadband wireless
access for WMANs (Wireless Metropolitan Area
network). When the aim is to provide a multi-service
wireless network, a key challenge is the optimal
allocation and utilization of the available raw data
transmission capacity of shared wireless links among
users and services. The key components in WiMAX QoS
guarantee are the admission control and the bandwidth
allocation in BS. The term ‘bandwidth’ is used to refer to                          Figure2: Fixed WiMAX
the data transmission capacity of the links. A number of          Figure 2 shows the Fixed WiMAX. It offers cost effective
WiMAX uplink scheduling algorithms in a single-hop                point to point and point to multi-point solutions. WiMAX
network, which is referred to as PMP (Point to Multi              provides fixed, portable or mobile non-line-of sight
Point).                                                           service from a base station to a subscriber station, also
WiMAX is an Institute of Electrical and Electronics               known as Customer Premise Equipment (CPE). Some
Engineers (IEEE) standard designated 802.16-2004 (fixed           goals for WiMAX include a radius of service coverage of
wireless applications) and 802.16e-2005 (mobile wire-             6 miles from a WiMAX base station for point-to-
less). Figure 1 shows the general infrastructure of               multipoint, non-line-of-sight service. This service should
WiMAX network.                                                    deliver approximately 40 Megabits per second (Mbps) for
The industry trade group WiMAX Forum has defined                  fixed and portable access applications. That WiMAX cell
WiMAX as a "last mile" Broadband Wireless Access                  site should offer enough bandwidth to support hundreds
(BWA) alternative to cable modem service.                         of businesses with very high speeds and thousands of
                                                                  residential customers with the equivalent of DSL services
Volume 1, Issue 2 July-August 2012                                                                               Page 280
   International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012                                          ISSN 2278-6856

from one base station.                                        network performance than without ODBA in WiMAX
   1.2 MOBILE WiMAX                                           network.

                                                              2. RELATED WORKS
                                                              The design objectives of the optimal bandwidth request
                                                              allocation algorithm for real-time service are as follows.
                                                              It should estimate the required bandwidth timely and
                                                              accurately. It should neither waste bandwidth nor suffer
                                                              from lack of bandwidth. It should satisfy delay
                                                              requirement and minimize jitter.
                                                              A. Jalali et. Al. [2] discussed in forward link data
                                                              throughput performance of a high data rate wireless
                                                              access system. Data is transmitted to many other Access
                                                              Terminals (AT) in a TDM designed. The transmission
                                                              rate at each AT varies and depends on each AT’s
                                                              measured Signal to Interference plus Noise Ratio (SINR).
               Figure 3: Mobile WiMAX
                                                              The forward link consists of a single data channel and
                                                              divided into 1.67msec time slots. In each time slot two
Figure 3 shows the Mobile WiMAX. It allows any
                                                              pilot bursts are inserted to aid in synchronization, SINR
telecommunications applications. The fixed wireless
application a step further and enables cell phone-like        estimation and coherent demodulation. Control channels
applications on a much larger scale. For example, mobile      and user payload are time multiplexed onto the forward
WiMAX enables streaming video to be broadcast from a          link. A forward link packet may occupy from 1 up to 16
speeding police or other emergency vehicle at over 70         time slots depending on the data rate. The Access
MPH. It potentially replaces cell phones and mobile data      Terminals (AT) predict the SINR and compute the rate
offerings from cell phone operators such as EvDo, EvDv        that the predicted SINR that can support while during the
and HSDPA. In addition to being the final leg in a            frame error rate. The throughput of CDMA-HDR which
quadruple play, it offers superior building penetration and   describe the excellent performance due to the efficient
improved security measures over fixed WiMAX. Mobile           rate control scheme, and the scheduling algorithm which
WiMAX will be very valuable for emerging services such        comes under the advantage of a mobile wireless system
as mobile TV and gaming.                                      for inherent multi-users, and advanced signal processing
Chakchai So-In, et.Al [1] provided extensive survey of        techniques. The system dedicates a 1.25 MHz RF carrier
recent scheduling proposals for WiMAX and discussed           to data services.
key issues and design factors. The scheduler designers        Mathew Andrews.et.Al [3] tells about the Quality of
need to be thoroughly familiar with WiMAX                     Service support for the multiple real-time data users,
characteristics such as the physical layer, frame format,     using a wireless channel. It concerned about the
registration process and so on. The goals of the              scheduling algorithms how exploiting asynchronous
schedulers explained are basically to meet QoS                variations of channel quality that can be used to enhance
guarantees for all service classes, to maximize the system    the channel capacity (i.e., enhancement the number of
output, to maintain the fairness, to minimize power           users with the desired (QoS). This Quality of Service
consumption, to have as less a complexity as possible and     (QoS) is considered in a specific combination of the data
finally to ensure the system scalability. In order to         rate and packet delay constraints of real-time data users,
improve the QoS of WiMAX demand, a new bandwidth              which are the requirements in obtaining high-speed data
allocation mechanism for WiMAX network is proposed,           networks. This is the way to handle the issue regarding
called On Demand Bandwidth Allocation (ODBA). The             efficient data scheduling for supporting QoS for real-time
proposed mechanism design has the management module           data. This problem can be considered as a multi-user
in the Subscribe Station (SS), which is for management        variable channel scheduling issue. The channel capacities
UL bandwidth, and one new module in the Base Station          of different users can be vary in time in an asynchronous
(BS). This includes UL/DL bandwidth allocation and            manner, the QoS of the users can be efficiently improved
service flow schedule. In order to solve the current issues   over scheduling schemes that cannot be considered
faced in WiMAX network, and to improve QoS demand,            channel conditions into account. Kaveh Pahlavan.et.Al
a new mechanism, ODBA is designed. It is an on demand         [4] discussed the existing technologies for wireless indoor
bandwidth allocation mechanism for WiMAX. The                 location systems. For finding accurate location in indoor
performance of ODBA mechanism and its behavior are            area following problems are being faced like the
evaluated, analyzed and compared with other algorithms        complexity of radio propagation and the ad hoc nature of
and those without ODBA in WiMAX network. The                  the deployed infrastructure. It gives the general overview
results show that the ODBA mechanism has higher               regarding the issue occurring in the indoor location

Volume 1, Issue 2 July-August 2012                                                                            Page 281
   International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012                                          ISSN 2278-6856

In a general term so many techniques are being used to           classes as defined by the standard. The relationship
find the accurate location in the indoor areas some of           between traffic characteristics and its QoS requirements
them are The Global Positioning System (GPS), Wireless           and the network performance has been showed. QoS
enhanced 911 (E-911) services. The above technologies            support in terms of bandwidth request and allocation for
are not capable of finding the accurate location. This           all type of traffic classes are discussed.
Indoor Geolocation is the key factor for public safety,          There are five types of service class to support the various
commercial and military applications. This technology is         type of traffic:-
very necessary for the safety of a country which can show              Unsolicited Grant Services (UGS)
the opponents reaction as well as for the commercial                   Real-Time Variable Rate (RT-VR)
purpose like residential areas and nursing homes. The                  Non real-time Polling Services (nrtPS)
challenge for TOA (Time of Arrival) based systems is to                Extended Real-Time Variable Rate (ERT-VR)
develop a signaling system and infrastructure that is                  BE (Best Effort)
inexpensive to design and deploy, complies with
frequency regulations, and provides a comprehensive                       Table 1: Mobile WiMAX QoS Classes
coverage for accurate ranging.
Kitti Wongthavarawat.et.Al [5] focused on a scheduling                                                       Example
                                                                     QoS Class      Supported Service
algorithm and admission control policy for IEEE 802.16                                                      Application
Broadband wireless access standard. This solution
provides QoS support to different traffic classes in terms          Unsolicite     Latency- and jitter-     Voice over
of bandwidth and maximum delay. The algorithm shows                 d Grant        sensitive                IP (VoIP)
the relationship between traffic characteristics and its            Services       applications with        without
QoS requirements and the network performance. This                  (UGS)          fixed-size data          silence
proposed algorithm provides QoS support to various Real                            packets at Constant      suppression
Time Applications and is also compatible with IEEE                                 Bitrate (CBR)
802.16 QoS signaling mechanisms. To support all types
of service flows, the proposed uplink packet scheduling             Real-Time      Real-time                Video and
algorithm uses a combination of strict priority service             Variable       applications with        audio
discipline. The proposed UPS is consisted of three                  Rate           variable-size data       streaming
modules: information module, scheduling database                    (RT-VR)        packet bursts
module and service assignment module. Guocong
                                                                    Non-Real-      Delay-tolerant           File transfers
Song.et.Al [6] used the Quality-of-Service (QoS)
                                                                    Time           applications with
provisioning over the multiple shared networks here
                                                                    Polling        variable-size data
investigated multi-user downlink data scheduling. It
                                                                    Services       packets and
provides fine flexibility and granularity for resource
                                                                    (nrtPS)        guaranteed bitrate
allocation for a network. Data traffic gets delay tolerance
according to that base station schedules their data
transmission according to the condition and because of
                                                                    Extended       Real-time                VoIP with
this it obtain multiuser diversity. If the relative latency of
                                                                    Real-Time      applications with        silence
tolerance of application is low then it effects gain of
                                                                    Variable       Variable Bitrate         suppression
multiuser diversity then resultant fluctuation of
                                                                    Rate           (VBR) data streams
independent channel occurs among the users. Wireless
                                                                    (ERT-VR)       and guaranteed
packet scheduling for fading channels which deals with
                                                                                   bitrate and delay
modifications of fair queuing scheduling or earliest due
date previously developed in wireline networks was
implemented.                                                                       Data streams with no     Web
                                                                    Best Effort
Dong-Hoon Song.et.Al [7] focused on a new structure of                             minimum service-         browsing,
QoS provided. This new QoS supports the real time                                  level demands            instant
traffic with high priority to an acceptable level for low                                                   messaging,
priority traffic. There are two new mobile interfaces for                                                   and data
wireless broadband specified as 802.16e and 802.20. 2 to                                                    transfer
6 GHz licensed bands mobility will be added in the
802.16e while 802.20 aims for operation in licensed              M.Settembre.et.Al [8] defines the fulfilling requirements
bands below 3.5GHz. Scheduling algorithm and                     of QoS while scheduling of IEEE 802.16 system and
admission control policies for IEEE 802.16 broadband             Protocol Data Units and adaptive modulation coding. It
wireless access standard are introduced. The proposed            provides the information of MAC scheduler which
solution which is practical and compatible to the IEEE           supports time division multiplexed voice and data and
802.16 standard provides QoS support to different traffic        voice over IP. The proposed scheduler gives the
classes. It includes QoS support for all types of traffic        information about connection status and current burst

Volume 1, Issue 2 July-August 2012                                                                                Page 282
   International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012                                          ISSN 2278-6856

profile for each terminal. The advantage of adaptive           metre (100-foot) wireless range of a conventional Wi-Fi
coding is that When radio link condition allow to use 16-      Local Area Network (LAN), offering a metropolitan area
QAM modulation, the available bandwidth triples with           network with a signal radius of about 50 km (30 miles).
respect to the case where QPSK modulation.                     WiMaX offers data-transfer rates of up to 75 Mbit/s,
Broadband Fixed Wireless Access (BFWA) systems are             which is superior to conventional cable-modem and DSL
solution to wired system in countries which are having         connections. Bong-Ho Kim.et.Al[12] discussed the
less developed infrastructure. QoS assures for critical        mobile WiMAX system undeniably has a higher system
application like video calling & IP telephoning. There are     capacity and a more complicated mechanism to provide a
some mechanisms like Fragmentation, Packing and                better Quality of Service (QoS) than earlier wireless
Payload Header Suppression (PHS) functionalities, allow        systems, such as Code-Division Multiple-Access (CDMA)
adapting packets length to the radio transmission,             or the Universal Mobile Telecommunications System
according to their QoS requirements and the available          (UMTS). In mobile WiMaX used to Orthogonal
bandwidth. Broadband Fixed Wireless Access (BFWA)              Frequency Division Multiple Access to flow the data. The
systems are a system which provides solution for wireless      most critical feature of mobile WiMax MAC is automatic
backhauling applications in the high data rates and            repeat request, and its parameters are resolute during a
Quality of Service (QoS).                                      connection-establishment step using MAC management
Jonny SUN.et.Al [9] proposes the Medium Access                 messages. WiMAX enables last-mile, point to-point, and
Control (MAC) and a new and efficient QoS scheduling           PMP elastic pipes that provide emerging IP-based end
strategy based on the hierarchical and distributed             devices. The main objective is to develop next generation
architecture is proposed for 802.16 BWA systems. This          wireless communication.
architecture includes two layers of schedulers, i.e. Base      Chakchai So.et.Al [13] discussed about mobile WiMaX
Station (BS) scheduler and Subscriber Station (SS)             uplink and downlink and mapping of these allocations. Its
scheduler. The BS scheduler grants bandwidth to SSs            enhanced version of algorithm called OCSA (One
according to the bandwidth request and reservation, then       Column Striping with non-increasing Area first mapping)
SS scheduler should re-distribute the received                 for rectangular mapping was introduced and then the
transmission opportunities among all of its connections.       enhanced version of that algorithm was very simple and
Broadband Wireless Access (BWA) system is developed            very fast implemented. The mapping process from logical
according to the demand always-on high-speed Internet          sub-channel to multiple physical subcarriers is called a
access.                                                        permutation. Mobile WiMAX uses a fixed frame-based
Debalina Ghosh.et.Al [10] discussed the WiMAX                  allocation. The mobile WiMax frame starts from uplink
technology can be used to deliver streaming audio or           to      downlink       mapping       allocation.     Neeraj
video to clients. Thus, Quality of Service (QoS) is very       POUDYAL1.et.Al         [14]    presented     about    novel
important for WiMAX networks. It proposed Efficient            measurement-based admission control policy to satisfy
heuristic algorithms for scheduling flows in a centrally       both the minimum bandwidth and maximum delay
scheduled multi-hop WiMAX network.               “Schedule     guarantees deterministically as required by some real-
efficiency” metric for comparing different flow                time applications. It explains about mobile station to
scheduling algorithms also provided. Admission control         proactively increase the chances of success of bandwidth.
and scheduling problem in multi-hop WiMAX networks             Fourth generation about schedulability criteria for
based on IEEE 802.16 was introduced. It described 5            admitting real time traffic system was developed. Full
algorithms which are schedule flow sub-channel (SFS),          multi-hop, multi-constrained extension with rtPS user-
timeslot-1, timeslot-2, min subchannel and the naive           level capacity parameters was proposed.
algorithm. It examines the geolocation of standard             Access of broad band internet in whole world is important
compliant WiMAX subscriber stations based on timing            for economic growth and development for any nation
adjust values captured from the air interface during           which can only be possible through WiMaX. It will
network entry and initial ranging. Field tests were            increase as the service costs decreases, with the exact rate
conducted to verify a linear correlation between timing        depending on the wider broadband and economic
adjust and distance. Repeated observations at fixed            landscape of each region. In developing regions where
distances established the variance within timing adjusts.      fixed broadband communications links are currently
Results of this field testing were extended to multiple base   insufficient and there is the need and drive for rapid
station networks modeled in computer simulation,               rollout of high-speed communications, there will be a
ultimately suggesting the possibility for geolocations         greater frequency of multiple-user subscriptions than in
based on WiMAX initial ranging with ten times greater          economically developed areas. Total fixed broadband
accuracy then similar methods applied to GSM.                  penetration, while much higher than W-CDMA
William Hrudey[11] focuses on WiMAX is a                       penetration on a worldwide basis, was less than 2% of the
communication technology for wirelessly delivering high-       population in Africa, 3.5% in Asia Pacific and the
speed Internet service to large geographical areas. It is a    Americas, 21% in Western Europe and 23% in North
part of a “fourth generation,” or 4G, of wireless-             America. This forecast is an ongoing project of the
communication technology, WiMaX far surpasses the 30-

Volume 1, Issue 2 July-August 2012                                                                              Page 283
   International Journal of Emerging Trends & Technology in Computer Science (IJETTCS)
       Web Site: www.ijettcs.org Email: editor@ijettcs.org, editorijettcs@gmail.com
Volume 1, Issue 2, July – August 2012                                          ISSN 2278-6856

WiMAX Forum that will continue to be used to educate             Shared        Wireless      Channels”,       IEEE
the market as the WiMAX ecosystem expands.                       Communications Society. 2004.
                                                            [7] Dong-Hoon Cho, Min-Su Kim and Ki-Jun Han,
3. CONCLUSION                                                    “Performance Analysis of the IEEE 802.16
                                                                 EWireless Metropolitan Area Network”, First
This article presents an overview of the scheduling
                                                                 International    Conference     on     Distributed
algorithms for the uplink traffic in WiMAX networks
                                                                 Frameworks      for    Multimedia    Applications
specifically issues associated with scheduling and QoS
                                                                 (DFMA’05). 2005.
provisioning. It also discusses the main features of the
                                                            [8] M. Settembre, P. Testa, R. Albanese, M. Mancini,
newly standardized mobile WiMAX, IEEE 802.16e. One
                                                                 Anagnina Roma – Italy testa, albanese, mancini.it.
of the major objectives of developing the next-generation
                                                                 Performance Analysis of an Efficient Packet-Based
wireless communication technology is to provide a higher
                                                                 IEEE 802.16 MAC Supporting Adaptive
link capacity and to increase the application/service
                                                                 Modulation and Coding, IEEE International
performance from the user perspective. We must consider
                                                                 Symposium on Computer Networks (ISCN' 06)
more precise and dynamic environmental conditions and
system characteristics, including the type of application
                                                            [9] Jonny SUN, Yanling YAO, Hongfei. Quality of
and the behavior of various scheduling algorithms. This
                                                                 Service Scheduling for 802.16 Broadband Wireless
enables an operator to achieve successful uplink
                                                                 Access Systems. 2006 IEEE.
bandwidth allocation planning while satisfying service
                                                            [10] Debalina Ghosh, Ashima Gupta. Admission
performance from the user perspective. With the
                                                                 Control and Interference-Aware Scheduling in
introduction of mobile WiMAX technology, it can be
                                                                 Multi-hop WiMAX Networks. 2007 IEEE.
expected that future work will focus on the mobility
                                                             [11] William (Will) Hrudey “Streaming video and
aspect and interoperability of mobile WiMAX with other
                                                                 audio content over Mobile WiMax Networks”,
wireless technologies. However, with the cost of
                                                                 SIMON FRASER UNIVERSITY, 2009.
infrastructure and competition from other technologies
                                                            [12] Bong-Ho Kim, Jungnam Yun, and Yerang Hur,
such as 3G/4G, it will be interesting to see how mobile
                                                                 Chakchai So-In, Raj Jain, and Abdel-Karim Al
WiMAX unfolds in the near future.
                                                                 Tamimi.     Capacity Estimation       and TCP
                                                                 Performance Enhancement over Mobile WiMAX
REFERENCES                                                       Networks. IEEE Communications Magazine, June
  [1] Chakchai So-In, Raj Jain and Abdel-Karim                   2009.
      Tamimi. Scheduling in IEEE 802.16e, “Mobile           [13] Chakchai So-In, “An Algorithm for Burst
      WiMAX Networks: Key Issues and a Survey”,                  Mapping with Strict QoS Requirements in IEEE
      IEEE     Journal     on   selected   areas    in           802.16e Mobile WiMAX Networks”, ICCAE,
      communications, VOL. 27, NO. 2, FEBRUARY                   2010.
      2009.                                                 [14] Neeraj POUDYAL, Ha Cheol LEE, Yong Jin
  [2] A. Jalali, R. Padovani, R. Pankaj, “Data                   KWON, Byung Seub LEE, Hwajeon Dong,
      Throughput of CDMA-HDR a High Efficiency-                  Gyeongin Ro,” Delay-bound Admission Control
      High Data Rate Personal Communication Wireless             for Real-time Traffic in Fourth Generation IMT-
      System” Qualcomm, Inc. 5775 Morehouse Drive                Advanced Networks based on 802.16m”, VOL 11,
      San Diego, USA(2000).                                      November 1, 2011.
  [3] Matthew Andrews, Krishnan Kumaran, Kavita             [15] Chakchai So-In, Raj Jain and Abdel-Karim Al
      Ramanan, Alexander Stolyar, Phil Whiting, Rajiv            Tamimi, WiMAX Forum® WiMAX™ Technology
      Vijayakumar, “Providing QoS over a Shared                  Forecast (2007-2012).
      Wireless Link”, IEEE Communications Magazine.         [16] ZhenTao Sun, Abdullah Gani, XiuYing Sun, Ning
      February 2001.                                             Liu. Liao Ning Agricultural Technology School
  [4] Kaveh Pahlavan and Xinrong Li, Juha-Pekka                  ShenYang City, “Improving QoS Of WiMAX By
      Mäkelä, “Indoor Geolocation Science and                    On_Demand Bandwidth Allocation Based On PMP
      Technology”, IEEE Communications Magazine.                 Mode”, China, Journal of Computers, VOL.6,
      February 2002.                                             No.10, October 2011.
  [5] Kitti Wongthavarawat and Aura Ganz, “Packet           [17] Jarno Pinola and Kostas Pentikousis, WIMAX
      scheduling for QoS support in IEEE 802.16                  ARTICALS, by VTT Technical Research Centre of
      broadband       wireless    access     systems”,           Finland.
      INTERNATIONAL              JOURNAL           OF
      Syst. 2003; 16:81–96.
  [6] Guocong Song and Ye (Geoffrey) Li, Leonard J.
      Cimini, Jr., Haitao Zheng, “Joint Channel-Aware
      and Queue-Aware Data Scheduling in Multiple

Volume 1, Issue 2 July-August 2012                                                                      Page 284

Description: International Journal of Emerging Trends & Technology in Computer Science (IJETTCS) is an online Journal in English published bimonthly for scientists, Engineers and Research Scholars involved in computer science, Information Technology and its applications to publish high quality and refereed papers. Papers reporting original research and innovative applications from all parts of the world are welcome. Papers for publication in the IJETTCS are selected through rigid peer review to ensure originality, timeliness, relevance and readability. The aim of IJETTCS is to publish peer reviewed research and review articles in rapidly developing field of computer science engineering and technology. This journal is an online journal having full access to the research and review paper. The journal also seeks clearly written survey and review articles from experts in the field, to promote intuitive understanding of the state-of-the-art and application trends. The journal aims to cover the latest outstanding developments in the field of Computer Science and engineering Technology.