1 Wireless Networks Lecture 10 Evolution of Wireless Networks (Part III) Dr. Ghalib A. Shah

2  Review of previous lecture  Limitation of 3G  4G ►Objectives ►Issues ►QoS ►Security ►Multimedia Service ►Applications  Convergence of Cellular and WLAN  Billing Issue  Wireless Networks  Summary of today

3 Review of last lecture  2.5G ►HSCSD ►GPRS ►EDGE ►IS-95B  3G ►UMTS/W-CDMA ►CDMA2000

4 Specifications of 2.5G and 3G standards TechnologyChannel BW DuplexInfrastructure ChangesNew Spectrum New handsets HSCSD200 KHzFDDSoftware upgrade at BSNoYes, New headsets provide 57.6 kbps on HSCSD and 9.6 kbps on GSM GPRS200 KHzFDDNew packet overlay at routers and gateways NoYes, new GPRS sets work at kbps, 9.6 kbps on GSM, dual-mode. EDGE200 KHzFDDNew TX/Rx at BS, software upgrade at BS, controller NoYes, new set work at 384 kbps on EDGE, GPRS at 144 kbps and GSM at 9.6 kbps, tri-mode W-CDMA5 MHzFDDCompletely new BSYesYes, new handsets work at 2 Mbps in WCDMA and rest as above IS-95B1.25 MHzFDDNew software at BSNoYes, IS-95B at 64kbps, IS- 95A at 14.4 kbps and IS-95 at 9.6 kbps Cdma2000 1xRTT 1.25 MHzFDDNew software at backbone, new channel cards at BS, new packet service node No1xRTT at 144 kbps and rest as above. Older sets will work. Cdma2000 1xEV(DO/DV) 1.25 MHzFDDNew software and cards upgrade to 1xRTT No1xEV at 2.4 Mbps and as above Cdma2000 3xRTT 3.75 MHzFDDBackbone modifications and channel cards at BS May be3xRTT at 2 Mbps and rest as above

5 Limitations of 3G  Difficulty of CDMA to provide higher data rates  Need for continuously increasing data rate and bandwidth to meet the multimedia requirements  Limitation of spectrum and it’s allocation  Inability to roam between different services  To provide a seamless transport end-to-end mechanism  To introduce a better system with reduced cost

6 4G  Provide a comprehensive IP solution where voice, data and streamed multimedia can be given to users on an "Anytime, Anywhere" basis, and at higher data rates than previous generations.  No formal definition but certain objectives ►Fully IP-based integrated systemIP-based ►Provides 100 Mbit/s and 1 Gbit/s speeds both indoors and outdoors, with premium quality and high security.quality security

7 4G Objectives  A spectrally efficient system (in bits/s/Hz and bit/s/Hz/site).spectrally efficient  A nominal data rate of 100 Mbit/s at higher relative speeds and 1 Gbit/s while client and station are in relatively fixed positions  High network capacity: more simultaneous users per cell  Smooth handoff across heterogeneous networks,handoff  Seamless connectivity and global roaming across multiple networksroaming  High quality of service for next generation multimedia support (real time audio, high speed data, HDTV video content, mobile TV, etc)  Interoperability with existing wireless standards  An all IP, packet switched network

8 Global information multimedia communication village

9 Convergence of High Speed Internet & Mobility a Major Driver of Future Wireless  The Wireless Industry has grown at enormous pace over the past decade.  Over 2.5 billion subscribers to cellular services are enjoying the benefits of staying connected while on the move.  With the growth in Internet, a wide range of services are accessed by users through a wired infrastructure.  The introduction of mobile Internet brought about by the convergence of Mobile & Internet technologies is the future objective.

10 4G Concept “The user has freedom and flexibility to select any desired service with reasonable QoS and affordable price, anytime, anywhere.”

11 Design Objectives

12 Heterogeneous Networks

13 Next Generation will also have specifically needs to resolve it’s own multiple issues  Heterogeneous networks  Access, handover  Location coordination, resource coordination  Adding new users  QoS, wireless security and authentication  Network failure backup  Pricing and billing

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15 Quality of Service (QoS)  Traffic generated by the different services will not only increase traffic loads on the networks, but will also require different quality of service (QoS) requirements (e.g., cell loss rate, delay, and jitter) for different streams (e.g., video, voice, data).  Providing QoS guarantees in 4G networks is a non-trivial issue where both QoS signalling across different networks and service differentiation between mobile flows will have to be addressed.

16 Quality of Service  One of the most difficult problems that are to be solved, when it comes to IP mobility, is how to insure the constant QoS level during the handover.  Depending on whether the new access router is in the same or some other sub network, we recognize the horizontal and vertical handover.

17 Hierarchical layer for 4G

18 Quality of Service  However, the mobile terminal can not receive IP packets while the process of handover is finished. This time is called the handover latency.  Handover latency has a great influence on the flow of multimedia applications in real-time.  Mobile IPv6 have been proposed to reduce the handover latency and the number of lost packets.  The field “Traffic Class” and “Flow Label” in IPv6 header enables the routers to secure the special QoS for specific packet series with marked priority.

19 MULTIMEDIA – Video Services  4G wireless systems are expected to deliver efficient multimedia services at very high data rates.  Basically there are two types of video services: bursting and streaming video services.  Streaming: is performed when a user requires real- time video services, in which the server delivers data continuously at a playback rate.  Bursting: is basically file downloading using a buffer and this is done at the highest data rate taking advantage of the whole available bandwidth.

20 Security  Security in wireless networks mainly involves authentication, confidentiality, integrity, and authorization for the access of network connectivity and QoS resources for the mobile nodes flow.  The heterogeneity of wireless networks complicates the security issue.  Dynamic reconfigurable, adaptive, and lightweight security mechanisms should be developed.  AAA (Authentication Authorization Auditing) protocols provide a framework for such suffered especially for control plane functions and installing security policies in the mobile node such as encryption, decryption and filtering.

21 Convergence of Cellular Mobile Networks and WLANs Benefits for  Operators ►Higher bandwidths. ►Lower cost of networks and equipment. ►The use of licence-exempt spectrum. ►Higher capacity and QoS enhancement. ►Higher revenue.  Users ►Access to broadband multimedia services with lower cost and where mostly needed. ►Inter-network roaming.

22 Applications  Virtual Presence: This means that 4G provides user services at all times, even if the user is off-site.  Virtual navigation: 4G provides users with virtual navigation through which a user can access a database of the streets, buildings etc.  Tele-geoprocessing applications: This is a combination of GIS (Geographical Information System) and GPS (Global Positioning System) in which a user can get the location by querying.

23 Applications  Tele-Medicine and Education: 4G will support remote health monitoring of patients. For people who are interested in life long education, 4G provides a good opportunity.  Crisis management: Natural disasters can cause break down in communication systems. In today’s world it might take days or 7 weeks to restore the system. But in 4G it is expected to restore such crisis issues in a few hours.

24 Multiple Operators and Billing System  In today’s communication market, an operator usually charges customers with a simple billing and accounting scheme.  A flat rate based on subscribed services, call durations, and transferred data volume is usually enough in many situations.  With the increase of service varieties in 4G systems, more comprehensive billing and accounting systems are needed.

25 Multiple operators and billing system Different type of services Different QoS requirements 4G billing system Multiple service providers It is challenging to formulate one single billing method that covers all the billing schemes involved.

26 WLANs  Use the unlicensed Industrial Scientific and Medical (ISM) band  ISM bands in US ►900 MHz ( MHz) ►2.4 GHz ( MHz) ►5.7 GHz ( MHz)  The most widely adopted standard

27 IEEE  A family of standards define Phy and MAC  IEEE : ►Infrared (IR) ►2.4Ghz ISM band with 1 or 2 Mbps  IEEE b: 11 Mbps in 2.4 GHz  IEEE a: 54 Mbps in 5.7 GHz  IEEE g: 54 MHz in 2.4 GHz  IEEE i: Security  IEEE e: QoS  IEEE f: Inter-access point protocol

28 Worldwide Interoperability for Microwave Access  WiMAX ►aimed at providing wireless data over long distances in a variety of ways, from point-to-point linkspoint-to-point full mobile cellular type access. ►Based on IEEE , also called wireless MAN ►last mile wireless broadband access as an alternative to cable and DSLlast mile

29 Wireless PAN  IEEE ►IEEE or Bluetooth Moderate data range up to 720 kbps Operates in ISM band 10 m to 100 m range ►IEEE Co-existence issues of IEEE and ►IEEE high rate Low power high data rate up to 20 Mbps Designed for multimedia applications over low power devices ►IEEE / ZigBee Low power with range of 100m Low rate about 20 kbps

30 Summary  Next Lecture ►Fundamental principles of Cellular networks