Introduction 1 Course: Wireless Networks

 Paper title” Evaluating network layer selfish behavior and a method to detect and mitigate its effects on MANETs”, publication in IEEE 15th International Multi Topic Conference INMIC 2012, Pakistan.  Paper title “A class based QoS model for Wireless Body Area Sensor Networks (WBASN)”, published in Research Journal of Recent Sciences, vol. 3, issue 7, July  Paper title “A novel QoS algorithm for Health Care applications of Body Area Sensor Networks”, published in Journal of Basic and Applied Scientific Research (JBASR), Vol. 4, No. 7, in July, Publications Published : Accepted :  Paper title” Application Specific Study and Analysis of Body Area Wireless Sensor Network Applications", The International Journal of Computer and Telecommunications Networking

Course Objectives The main objective of this course is to introduce the fundamental concepts & issues in the field of wireless networks, develop the foundations of the students and review the current research trends in the area specified Pre requisites: Computer Networks

Literature Books W. Stallings, “Wireless Communications and Networks”, Prentice Hall, Vijay Garg, “Wireless communication and networking”, Morgan Kaufman Agarwal & Zeng, “Introduction to wireless and mobile systems”, Indian edition, Cenage learning, Murthy & Manoj,”Ad Hoc wireless Networks architecture and protocols”, Pearson Education Background Reading Behrouz.A.Forouzan, ”Data communication and networking”, 3 rd or 4 th Edition McGraw Hill. Research & Review

Background of Wireless Communication and Networks

Wireless Comes of Age r Guglielmo Marconi invented the wireless telegraph in m Communicated by encoding alphanumeric characters in an analog signal. m Sent the first telegraphic signals across the Atlantic Ocean from Cornwall, England to Signal Hill at St. John’s, Newfoundland in 1901 (three dots for the letter S). m In 1902, the first complete message was sent from Table Head in Glace Bay, Cape Breton to Cornwall, England.

Wireless Comes of Age r Communications satellites were launched in 1960s for carrying voice traffic. m Started carrying television and other signals shortly afterwards. r The first public cellular phone system, known as AMPS (Advanced Mobile Phone Service) was introduced in 1979 in the United States. m Others soon followed like NMT (Scandinavia), TACS (UK), and NAMTS (Japan), plus other country specific systems, each different from the others. r In the 1990’s, the next generation of cellular systems started to appear (PCS, GSM, etc.). r Advancements are now continuous!

Milestones in Wireless Communications

Broadband Wireless Technology Higher data rates obtainable with broadband wireless technology Graphics, video, audio Shares same advantages of all wireless services: convenience and reduced cost Service can be deployed faster than fixed service No cost of cable plant Service is mobile, deployed almost anywhere

Why Wireless? Wireless communication has several advantages over wired alternatives: Wireless service is mobile and can be deployed almost anywhere. Wireless service can be deployed faster than fixed service. There are no cabling costs, which can be prohibitively expensive in some cases. Wireless users are not tethered down and are free to be relatively mobile... anywhere, anytime computing and communications! A new wireless user to the network does not need a free port or cable to join.

Why Not Wireless? There are limitations and difficulties with using wireless communications, however. Wireless may be cheaper to deploy in some cases, but it may have usage fees (cellular service is still NOT cheap). Issues of security (for example, WEP). Again, we have many incompatible standards that do not work well with each other. Some mobile or wireless devices have hardware or software limitations (small screen sizes, text only displays, support for WML but not HTML, etc.). Wireless networks do not support the same data rates as wired networks with the same reliability. Wireless broadband needs time to get mature.

Types of Wireless Networks Terrestrial Networks Satellite-Based Networks There are two main types of wireless networks.

Types of Wireless Networks Satellite-Based Networks Satellite-based antennae in a stable orbit above the Earth relay communications from two or more stations on or near the Earth. Coverage areas can be tremendous. Very high data rates are available. Deployment costs can be enormous. Propagation delays can be potentially quite large due to the distance the signals must travel. Although satellite links are subject to short term outages or degradations, the quality of transmission is normally extremely high.

Types of Wireless Networks Terrestrial Networks All network devices and users are located on Earth. Coverage areas are relatively small in comparison to satellite networks. Data rates available vary with the technology. Deployment costs can vary, but they tend to be lower than deploying a satellite system. Propagation delays are negligible in comparison. Quality of transmission can vary widely based on the surrounding conditions (there are more chances for potential interference from common sources).

Types of Terrestrial Wireless Networks There are two main types of terrestrial wireless networks. Wireless Local Area Networks Mobile users communicate directly with each other (ad hoc mode) or indirectly through a base station or access point within a radius of a few tens of metres. Global Internet access is provided by a wired connection from the base station or through one member of the ad hoc network. Examples: and Bluetooth.

Wide-Area Wireless Access Networks Mobile users communicate through a base station managed by a telecommunications provider and serves users within a radius of tens of kilometers. Global Internet access is provided through the wireless network, usually as an add-on service provided by the telecommunications provider. Example: Cellular service. 16 Types of Terrestrial Wireless Networks

Mobile and Wireless Applications Mobile wireless applications may be categorized in increasing order of complexity: Simple Messaging The ability to send simple text messages between wireless users (instant messages or messages). Already available on most modern systems. Data speeds of 9.6 or 14.4 Kbps are required. Basic Internet Access This includes downloading simple information like weather reports, stock updates, news, sports, etc. Available on most modern systems that support WAP. Similar data rates to simple messaging.

Wireless Application Protocol Stack MicroBrowser (WML, WMLScript, WTA, WTAI) Runs on top of WDP Provided lightweight X-oriented service Unreliable 1-way request Reliable 1-way/2-way req./response Lightweight SSL Uses WIM/PKI-Cards Datagram service on different bearers Convergence between bearer services Different Wireless Tech. Source: WAP Forum

Mobile and Wireless Applications Network-Enhanced Applications These require interaction with the network and the user; a high level of network intelligence is required. Examples include various location or context-sensitive services and applications. Some of these services are available now; expect many more in the future. Data rates vary from modest (10 Kbps) to possibly many times that amount. Secure Communications A number of applications require secure access. These application many need high bandwidth access and likely require encryption.

Mobile and Wireless Applications Multimedia Messaging Non real-time messaging with different forms of multimedia, including text, images, audio, and video. The Multimedia Messaging Service (MMS) is now being widely adopted to support this ability. High data rates of many hundred Kbps is required for timely delivery. Advanced Internet Access The basic aim here is to provide the same level of service as any wired Internet access. Needs to support real-time multimedia and other advanced Internet applications. Very high data rates of many hundred Kbps or even several Mbps can be required here.

Summary Course Objectives Background Type of Wireless Networks Mobile and wireless Applications