Chettinad college of engineering and technology- karurWIRELESS COMMUNICATION : Chettinad college of engineering and technology- karurWIRELESS COMMUNICATION Submitted by
T.Yuvapiriyaa Wireless Comes of Age : Wireless Comes of Age Guglielmo Marconi invented the wireless telegraph in 1896
Communication by encoding alphanumeric characters in analog signal
Communications satellites launched in 1960s
Advances in wireless technology
Radio, television, mobile telephone, communication satellites
Satellite communications, wireless networking, cellular technology Broadband Wireless Technology : Broadband Wireless Technology Higher data rates obtainable with broadband
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 Limitations and Difficulties of Wireless Technologies : Limitations and Difficulties of Wireless Technologies Wireless is convenient and less expensive
Limitations and political and technical difficulties inhibit wireless technologies
Lack of an industry-wide standard
Device limitations Modes of wireless communication : Modes of wireless communication Wireless communication can be via:
Radio frequency communication.
Microwave communication, for example long-range line-of-sight via highly directional antennas, or short-range communication.
Infrared (IR) short-range communication, for example from remote controls or via Infrared Data Association (IrDA).
Applications may involve point-to-point communication, point-to-multipoint communication, broadcasting, cellular networks and other wireless networks. Transmission Fundamentals : Transmission Fundamentals Data communications concepts
Includes techniques of analog and digital data transmission
Multiplexing Multiplexing : Multiplexing Multiplexing is sending multiple signals or streams of information on a carrier at the same time in the form of a single, complex signal and then recovering the separate signals at the receiving end.
In analog transmission, signals are commonly multiplexed using frequency-division multiplexing (FDM).
In digital transmission, signals are commonly multiplexed using time-division multiplexing (TDM). Communication Networks : Communication Networks Comparison of basic communication network technologies
ATM Slide 9: An overview for networking mobile end-system Internet router router router end-system FA MN home network foreign network (current physical network for the MN) CN Circuit switching and packet switching : Circuit switching and packet switching A type of communications in which a dedicated channel is established for the duration of a transmission.
The other common communications method is packet switching, which divides messages into packets and sends each packet individually. The Internet is based on a packet-switching protocol, TCP/IP.
Packet-switching networks are more efficient if some amount of delay is acceptable.
Circuit-switching networks are sometimes called connection-oriented networks. Frame Relay : Frame Relay Frame relay is a telecommunication service designed for cost-efficient data transmission for intermittent traffic between local area networks (LANs) and between end-points in a wide area network (WAN).
Frame relay puts data in a variable-size unit called a frame and leaves any necessary error correction (retransmission of data) up to the end-points, which speeds up overall data transmission. Protocols and the TCP/IP Protocol Suite : Protocols and the TCP/IP Protocol Suite Protocol architecture
Overview of TCP/IP
Open systems interconnection (OSI) reference model
Internetworking OSI model and TCP/IP protocol siute : OSI model and TCP/IP protocol siute Slide 15: OSI model The Open Systems Interconnection model (OSI model) is a product of the Open Systems Interconnection effort at the International Organization for Standardization. It is a way of sub-dividing a communications system into smaller parts called layers.
In 1978, work on a layered model of network architecture was started and the International Organization for Standardization (ISO) began to develop its OSI framework architecture. Layers of OSI model and their protocols : Layers of OSI model and their protocols 7.Application Layer
· DNS · FTP · HTTP · SMTP · Telnet
6. Presentation Layer
· XDR · TLS · SSL
5. Session Layer
SAP · SIP · PPTP
4. Transport Layer
TCP · UDP · SCTP · DCCP
3. Network Layer
· ICMP · IGMP
2. Data Link Layer
ARP · RARP · Ethernet · Frame relay
1. Physical Layer
· Ethernet · USB · Bluetooth TCP/IP protocol suite : TCP/IP protocol suite The Internet Protocol Suite is the set of communications protocols used for the Internet and other similar networks. It is commonly also known as TCP/IP
The Internet Protocol Suite, like many protocol suites, is constructed as a set of layers. Each layer solves a set of problems involving the transmission of data.
The TCP/IP model consists of four layers From lowest to highest, these are the Link Layer, the Internet Layer, the Transport Layer, and the Application Layer. Concept of TCP/IP layers : Concept of TCP/IP layers The TCP/IP suite uses encapsulation to provide abstraction of protocols and services. Such encapsulation usually is aligned with the division of the protocol suite into layers of general functionality.
In general, an application (the highest level of the model) uses a set of protocols to send its data down the layers, being further encapsulated at each level.
This may be illustrated by an example network scenario, in which two Internet host computers communicate across local network boundaries constituted by their internetworking gateways (routers). Protocols for each layer : Protocols for each layer Application layer:
DNS, TFTP, TLS/SSL, FTP, HTTP, IMAP, IRC, NNTP, POP3
TCP, UDP, DCCP, SCTP, IL, RUDP, RSVP
IP (IPv4, IPv6), ICMP, IGMP
ARP, RARP, OSPF (IPv4/IPv6), IS-IS, NDP Wireless Networking : Wireless Networking Examines major types of networks
Fixed wireless access schemes
Use of mobile IP and Wireless Access Protocol (WAP) to provide Internet and Web access Mobile IP and Wireless Access Protocol : Mobile IP and Wireless Access Protocol Modifications to IP protocol to accommodate wireless access to Internet
Wireless Application Protocol (WAP)
Provides mobile users access to telephony and information services including Internet and Web
Includes wireless phones, pagers and personal digital assistants (PDAs) Bluetooth : Bluetooth Bluetooth is an open specification for wireless communication and networking
Other wireless devices References : References http://docs.hp.com/en/T1428-90017/ch01s05.html
http://www.wireless-center.net/General-Wireless/1162.html Conclusion : Conclusion The benefit of wireless networks is driving the explosive growth of the WLAN market. Where security has been the single largest concern for wireless network deployment in the corporate setting, strong security solutions are available to make wireless networks as secure as wired networks
Wi-Fi Protected Access (WPA) is capable of preventing most sophisticated attacks on wireless networks
This approach offers a pragmatic solution to wireless security and can resolve the single largest barrier to WLAN deployment for IT managers