BUS1MIS Management Information Systems Semester 1, 2012 Week 5 Lecture 1

Networks, Telecommunications and Mobile Technologies We are living in an increasingly wireless present …… …. and hurtling ever faster towards a wireless future. The tipping point of ubiquitous, wireless, handheld, mobile computing is close. Baltzan et al. p. 295

Networks, Telecommunications and Mobile Technologies Companies large and small from all over the world are using networked systems, including the Internet, and wireless technologies to gain competitive advantages. As a business student, you must understand the concepts of network architecture and mobile technology to be able to understand how IT can be used to improve business.

Networks, Telecommunications and Mobile Technologies For example: Cirque du Soleil - available from the textbook (BDIS) web site) During the film list all usages of networks, telecommunications and wireless technologies.

Networks, Telecommunications and Mobile Technologies Learning Objectives Reference: Appendix C, on-line website for the text … and Chapter 7 text Compare local area networks (LANs), wide area networks (WANs) and metropolitan networks (MANs) List and describe the four components that differentiate networks Compare the two types of network architectures Explain topology and the different types found in networks Describe TCP/IP along with its primary purpose Identify the different media types found in networks

Central processing unit (CPU) RAM ROM Hard drive Secondary storage Input devices Primary storage output devices communication devices The `world’

What is a computer network? Networks `A computer network is a communications, data exchange, and resource-sharing system created by linking two or more computers and establishing standards, or protocols, so that they can work together’

Networks Network types 1.Local area networks (LANs) 2.Wide area networks (WANs) 3.Metropolitan area networks (MANs)

Local area networks typically connect computers and other devices within a small geographical area e.g. a building such as a school, library, private home etc.

Wide area networks typically span a larger geographic area, for example a city, a state or a country. Networks which service large organisations with multiple sites would be classified as a wide area network. The wide area network that spans the entire globe is the internet

Networks that lie somewhere in between are sometimes referred to as metropolitan area networks. They typically span a city. For example - Swindon, UK Swindon, UK

Networks Network components (other than computers, printers, file servers ) A protocol [a set of communication rules] Network interface cards [a piece of hardware that can be plugged into a computer to allow it to communicate with other computers] Cables [ the media which connects devices] Hub (switch or router) [ a piece of hardware that manages the communications between devices --- the `traffic cop’] Network performance [see Baltzan et al. p 304 – 6] Bandwidth refers to the capacity of a network to transmit data i.e. the volume of data that can be transmitted per unit of time. Broadband refers to high speed internet connections transmitting data at speeds greater than 200 kilobytes per second (Kbps).

Networks Broadband speeds The National Broadband Network The National Broadband Network is expected to deliver download speeds of 100Mbps. The 3G (mobile phone network) currently delivers 3.6Mbps Telstra’s 4G network opened in January Mbps Telephone line based

Networks How are networks differentiated? … in terms of the network architecture … in terms of the network topology … in terms of the network protocols … in terms of the network media

Networks How are networks differentiated? Network architecture Client-server A central computer (a `server’) stores data and application files. Other computers in the network (the `clients’) can request applications and data files from the server. The software which manages all of this (i.e. steering information between devices, managing security and the users) is known as the network operating system (e.g. Novell Netware) See p.C.5 for the role of packet switching and the router

Networks How are networks differentiated? Network architecture Peer-to-peer … all computers in the network can share files and use connected devices No file server For example, Napster and Kazaa (file sharing of music files across the internet)

Networks How are networks differentiated? Network topology … `geometric’ shape BUS topology STAR topology RING topology

BUS – all devices connected to a central cable (called a bus). Inexpensive and suitable for small networks STAR – all devices connected to a central device (called a hub). Relatively easy to install and manage, however all data has to go through the hub (potential bottlenecks) RING – Devices connected to each in a closed loop (each device directly connected to exactly two others). This is an expensive option, offering high band width and networks that can span large distances.

Networks Network protocols How are networks differentiated? When some data is sent over a network it is broken into packets of a set number of characters. A protocol is a standard specifying the format of the packets and rules to be followed during data transmission. DestinationSourceHops1 st data character 2 nd data character 3 rd data character 4 th data character ………..End of Message Example of a data packet

Networks Network protocols How are networks differentiated? Two common protocols … Ethernet (Local Area network) Transmission Control Protocol/Internet Protocol (TCP/IP) (Internet)

Networks Ethernet: physical network interface technology for most LANs A firewall (hardware and/or software) protects a network form the outside world. It analyses data/information that is entering or leaving the network. It looks for `suspicious things’ such as files which contain viruses etc. See p Baltzan et al. for a discussion of network security, including the use of passwords and data encryption

Networks See Appendix C (p c.7 – c.9) for a more detailed description of each Transmission Control Protocol/Internet Protocol (TCP/IP) TCP provides the transport functions for data transmission across a network e.g. ensuring that amount of data received matches that sent IP acts as a `postmaster’ i.e. provides an addressing and routing mechanism for data transmission IP address – computers on the Internet have an IP address – The world has recently run out of IP addressesThe world has recently run out of IP addresses.

Networks An intranet is an internalised portion of the Internet, protected from outside access which allows an organisation to restrict access to application software and information to only its employees. See p. 116 of Baltzan et al. Internet (public) organisation Intranet (private) firewall

Networks How are networks differentiated? Transmission Media wire media (twisted pair, coaxial cable, fibre-optic cable) wireless media

WiMAX (worldwide Interoperability for Microwave Access) is a telecommunications technology aimed at providing wireless data over long distances in a variety of ways, from point-to-point links to full mobile cellular type access Baltzan et al. p.324 Wireless Networks (WiFi)