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C7- Telecommunications, The Internet, and Wireless Technology. Telecommunications and Networking in . Today’s Business World. A networking and communications revolution led by Internet-based technologies Convergence of telephone and computer networks
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C7- Telecommunications, The Internet, and Wireless Technology
Telecommunications and Networking in Today’s Business World • A networking and communications revolution led by Internet-based technologies • Convergence of telephone and computer networks • Voice and data communication networks are becoming faster, more portable, and less expensive 7-2
What is a computer network? • Consists of two or more connected computers • Each computer contains a network interface card (NIC) • The connection medium • telephone wire, coaxial cable, or radio signal in the case of cell phone and wireless local area networks • Network Operating System (NOS) • Routes and manages communications on the network and coordinates network resources • Dedicated server computer • Hubs • Routers 7-3
What is a computer network? ... • Most networks contain a switch or a hub acting as a connection point between the computers • Hubs are simple devices that send packets of data to all other connected devices • Switches can filter and forward data to specified locations with some intelligence • Routers send packets of data though different networks 7-4
A Simple Network • Where is the • Client computers • Network operating system • Server computer • Cable (wiring) • Network interface cards (NICs) • Switches, and a router. Figure 7-1 7-5
Client/Server Computing • A distributed processing model • some processing power is located within small, inexpensive client computers • The clients are linked to one another • The network is controlled by a network server computer • The server sets the rules of communication for the network • provides every client with an address so others can find it on the network 7-7
Packet Switching Key Digital Network Technologies Message broken down to packets Sent through different communication path Reassembled at destination 7-8
TCP/IP Protocol Key Digital Network Technologies • TCP/IP uses a suite of protocols: • TCP: Transmission Control Protocol – establish a connection • IP: Internet Protocol – handles delivery of packets • set of rules governing transmission of information- used by and all Internet devices • TCP/IP provides for breaking up digital messages into packets, routing them to the proper addresses, and then reassembling them into coherent messages
The Internet • It is a network • Links hundreds of thousands of individual networks all over the world • Composed of computers and other devices that are logically linked together by a unique address space based on Protocol • Where devices are able to support communications using TCP/IP • That provides high-level services layered on a communication and network infrastructure • Most homes connect to the Internet by subscribing to an Internet Service Provider (ISP) 7-25
Internet Services • E-mail: Person-to-person messaging; document sharing • Usenet newsgroups: Discussion groups on electronic bulletin boards • Chatting and instant messaging: Interactive conversations • Telnet: Logging on to one computer system and doing work on another • FTP: Transferring files from computer to computer • World Wide Web: Retrieving, formatting, and displaying information (text, audio, video, graphics) using hypertext links 7-30
Internet Features Hypertext Searching information Search engines Intelligent agents shopping bots Web logs (blogs) Semantic web • Web pages based on a standard Hypertext Markup Language (HTML) • Web browsers request web pages stored on an Internet host server using Hypertext Transfer Protocol (HTTP) • The address of a web page is its Uniform Resource Locator (URL)
Technologies And Tools For Communication And E-business Intranets and Extranets Virtual Private Networks (VPN) A private network configured within a public network to take advantage of economies of scale and facilities of larger networks Secure connection between two points on Less expensive, more flexible, greater bandwidth than non-IP networks • Intranet: • an internal organizational network that provides access to data across the enterprise • Protected from public visits by firewalls • Extranet: • Authorized visitors (vendors, customers) are given limited access to an internal intranet
The Wireless Revolution • Mobile phones are now platforms for delivering digital data, used for recording and downloading photos, video and music, Internet access, and transmitting payments • An array of technologies provides high-speed wireless access to for PCs and other wireless handheld devices and cell phones • Businesses increasingly use wireless to cut costs, increase flexibility, and create new products and services
Wireless Transmission Media and Devices • All wireless media rely on various parts of the electromagnetic spectrum • Microwave systems transmit high-frequency radio signals through the atmosphere • Communication satellites are used for geographically dispersed organizations • Blackberry: email handheld • PDAs: small handheld computers • electronic scheduler • Cellphones: use radio waves to communicate with towers in cells • message passed from cell to cell • Smartphones: can save information, access Internet
Mobile Wireless Standards for Web Access • Wireless Application Protocol (WAP): Uses Wireless Markup Language (WML) and microbrowsers • Bluetooth • Creates small Personal Area Networks (PAN) • Can link up to 8 devices in 10-m area • Low power requirements
Wi-Fi • Three standards: 802.11a, 802.11b, 802.11g • Infrastructure mode: Devices use access point to communicate with wired network • Ad-hoc mode (peer-to-peer): Wireless devices communicate directly with each other • Benefits of Wi-Fi • Low-cost to provide Internet access to conference rooms, workstations • Allows hot-spots in public areas such as university campuses, airports … • Challenges • Security • Susceptibility to interference
Wireless in Heath Care • Electronic Medical Record (EMR) retrieval • Wireless note taking for patient charts • Lab test results • Prescription generation • Medical databases
Wireless Technology In The Enterprise • Pervasive Computing • Wireless technologies are pushing computing into every facet of life, including cars, homes, office buildings, tools and factories; providing connections anywhere and anytime • Wireless sensor networks (WSNs) • Networks of interconnected wireless devices that are embedded into the physical environment to provide measurements of many points over large spaces