10/100/1000 Mbps Ethernet 100 Mbps FDDI 155/620 Mbps ATM 4/10/45 Mbps Wireless

Transcription

1 TRANSMISSION MEDIA

2 LOCAL AREA NETWORK (LAN) TECHNOLOGY 10/100/1000 Mbps Ethernet 100 Mbps FDDI 155/620 Mbps ATM 4/10/45 Mbps Wireless page - 2

3 LAN TECHNOLOGY Protocol What is a Protocol? A protocol is a set of rules that governs the communications between computers on a network. These rules include guidelines that regulate the following characteristics of a network: access method, allowed physical topologies, types of cabling, and speed of data transfer. page - 3

4 Protocol Protocol (communications protocol)= standards that specifically address how the devices on a network communicate, i.e How the data is packaged for transmission How receiving devices acknowledge signals from sending devices How errors are detected and handled

5 LAN TECHNOLOGY Protocol Logical topologies are bound to network protocols and describe how data is moved across the network. Ethernet, LocalTalk,Token ring for wired networks TCP/IP and WAP for internet WiFi for wireless networks Bluetooth, for short range wireless network page - 5

6 LAN Technology Protocol : Ethernet the most widely used wired networks protocol Early Ethernet network were half duplex, uses an access method called CSMA/CD (Carrier Sense Multiple Access/Collision Detection), a system where each computer listens to the cable before sending anything through the network to avoid collisions. Since 1997 Ethernet uses full duplex communication, that does not require listening to other messages and no collisions occur. page - 6

7 The Ethernet protocol allows for linear bus, star, or tree topologies. Data can be transmitted over wireless access points, twisted pair, coaxial, or fiber optic cable. Early Ethernet protocols (10BASE-T) support transmissions rate 10 Mbps Today LAN Technology Protocol : Ethernet 100BASE-T or 100BASE-TX 1000Mbps (1Gbps 10Gigagbit Ethernet 10Gbps page - 7

8 LAN TECHNOLOGY Protocol : Localtalk a network protocol that was developed Macintosh computers. used a method called CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance), where a computer signals its intent to transmit before it actually does so. allows for linear bus, star, or tree topologies using twisted pair cable. disadvantage : slow speed (only 230 Kbps). page - 8

9 LAN TECHNOLOGY Protocol : Token Ring developed by IBM in the mid-1980s. access method involves token-passing. the computers are connected so that the signal travels around the network from one computer to another in a logical ring. A single electronic token moves around the ring from one computer to the next. If a computer does not have information to transmit, it simply passes the token on to the next workstation. If a computer wishes to transmit and receives an empty token, it attaches data to the token. The token then proceeds around the ring until it comes to the computer for which the data is meant- the data is captured by the receiving computer. page - 9

10 LAN TECHNOLOGY Protocol Token Ring The Token Ring protocol requires a star-wired ring using twisted pair or fiber optic cable. It can operate at transmission speeds of 4 Mbps or 16 Mbps. page - 10

11 LAN TECHNOLOGY Protocol FDDI Fiber Distributed Data Interface - a network protocol that is used primarily to interconnect two or more local area networks, often over large distances. access method involves token-passing. uses a dual ring physical topology. Transmission normally occurs on one of the rings; if a break occurs, the system keeps information moving by automatically using portions of the second ring to create a new complete ring. A major advantage of FDDI is speed. It operates over fiber optic cable at 100 Mbps. page - 11

12 CABLING

13 LAN TECHNOLOGY CABLING Cable is the medium through which information usually moves from one network device to another. several types of cable are commonly used with LANs. In some cases, a network will utilize only one type of cable, other networks will use a variety of cable types page - 13

14 LAN TECHNOLOGY CABLING Types of Cables Unshielded Twisted Pair (UTP) Cable Shielded Twisted Pair (STP) Cable Coaxial Cable Fiber Optic Cable page - 14

15 LAN TECHNOLOGY CABLING: Unshielded Twisted Pair (UTP) Cable The cable has four pairs of wires inside the jacket. Each pair is twisted with a different number of twists per inch to help eliminate interference from adjacent pairs and other electrical devices. page - 15

16 LAN TECHNOLOGY CABLING: Unshielded Twisted Pair (UTP) Cable Categories Types Category 1 Voice (Wayer Telefon) Use Category 2 Data to 4 Mbps (LocalTalk) Category 3 Data to 10 Mbps (Ethernet) Category 4 Category 5 Data to 20 Mbps (16 Mbps Token Ring) Data to 100 Mbps (Fast Ethernet) page - 16

17 UTP Cable Standards Cat 3 UTP to carry data up to 10Mbit/s. standard cable for use with Ethernet 10Base-T. Cat 5 UTP to carry Ethernet up to 100Mbit/s and ATM up to 155Mbit/s. standard cable for use with Ethernet 100Base-TX. Cat 5e UTP Cat 6 UTP an enhanced version of Cat 5 UTP. to carry data up to 1000Mbit/s. standard cable for use with Ethernet 1000Base-T. used to extend the distance of 100Base-TX cable runs up to 350 meters. similar to Cat 5 UTP, except that it is designed and manufactured to even stricter standards.

18 LAN TECHNOLOGY CABLING: Unshielded Twisted Pair (UTP) Cable The standard connector for unshielded twisted pair cabling is an RJ-45 connector RJ=Registered Jack page - 18

19 TEKNOLOGI LAN Penkabelan : Unshielded Twisted Pair (UTP) Cable A disadvantage of UTP is that it may be susceptible to radio and electrical frequency interference. page - 19

20 LAN TECHNOLOGY CABLING: Shielded Twisted Pair (STP) Cable STP is a type of cable consists of two individual wires wrapped in a foil shielding to help provide a more reliable data communication. suitable for environments with electrical interference; however, the extra shielding can make the cables quite bulky. often used on networks using Token Ring topology. page - 20

21 LAN TECHNOLOGY CABLING: CO-AXIAL CABLE Coaxial cabling has a single copper conductor at its center. A plastic layer provides insulation between the center conductor and a braided metal shield The metal shield helps to block any outside interference from fluorescent lights, motors, and other computers. page - 21

22 LAN TECHNOLOGY CABLING: CO-AXIAL CABLE Coaxial Cable Connectors The most common type of connector used with coaxial cables is the Bayonet- Neill-Concelman (BNC) connector Different types of adapters are available for BNC connectors, including a T- connector, barrel connector, and terminator. page - 22

23 LAN TECHNOLOGY CABLING: FIBRE OPTICS consists of a center glass core surrounded by several layers of protective materials It transmits light rather than electronic signals eliminating the problem of electrical interference. ideal for certain environments that contain a large amount of electrical interference.. able to transmit signals over much longer distances than coaxial and twisted pair. page - 23

24 LAN TECHNOLOGY CABLING Summary of Ethernet cabling Specification Cable Type Maximum length 10BaseT Unshielded Twisted Pair 100 meters 10Base2 Thin Coaxial 185 meters 10Base5 Thick Coaxial 500 meters 10BaseF Fiber Optic 2000 meters page - 24

25 LAN TECHNOLOGY CABLING Cable & topology Topologi Fizikal Kabel Umum Protokol Umum Linear Bus Star Coax Twisted Pair Fiber Twisted Pair Fiber Ethernet LocalTalk Ethernet LocalTalk Star-Wired Ring Twisted Pair Token Ring Tree Coax Twisted Pair Fiber Ethernet page - 25

26 NETWORK OPERATING SYSTEM (NOS) Software that controls a network and its message (e.g. packet) traffic and queues, controls access by multiple users to network resources such as files, and provides for certain administrative functions, including security. coordinate the activities of multiple computers across a network. acts as a director to keep the network running smoothly. page - 26

27 NETWORK OPERATING SYSTEM (NOS) A NOS is not the same as the networking tools provided by some existing OSs, Windows XP for instance. An NOS is an OS that has been specifically written to keep networks running at optimal performance. Some popular NOSs include: Windows NT, IBM AIX, Sun Solaris, Windows 2000 Server, Windows Server 2003,Inferno Novell NetWare, Red Hat Linux, BSD page - 27

28 NETWORK OPERATING SYSTEM (NOS) The two major types of network operating systems are: : Peer-to-Peer Client/Server page - 28

29 NETWORK OPERATING SYSTEM Peer to Peer In a peer-to-peer network, all computers are considered equal; they all have the same abilities to use the resources available on the network allow users to share resources and files located on their computers and to access shared resources found on other computers. do not have a file server or a centralized management source designed primarily for small to medium local area networks. AppleShare and Windows for Workgroups are examples of programs that can function as peerto-peer network operating systems. page - 29

30 NETWORK OPERATING SYSTEM Peer to Peer Advantages Less initial expense - No need for a dedicated server. Setup - An operating system (such as Windows XP/ ) already in place may only need to be reconfigured for peer-to-peer operations. page - 30

31 NETWORK OPERATING SYSTEM Peer to Peer Disadvantages Decentralized - No central repository for files and applications. Security - Does not provide the security available on a client/server network. P2P from Microsoft page - 31

32 SISTEM PENGOPERASI RANGKAIAN (NOS) Jenis : Peer to Peer Kekurangan rangkaian "peer-to-peer": Tidak Berpusat - Tidak ada sistem berpusat untuk fail dan perisian apalikasi. Keselamatan - sistem keselamatan yang lebih rendah. P2p from microsoft page - 32

33 NETWORK OPERATING SYSTEM Client/Server page - 33 allow the network to centralize functions and applications in one or more dedicated file servers the file servers become the heart of the system, providing access to resources and providing security. individual workstations (clients) have access to the resources available on the file servers. Novell Netware and Windows 2000 Server are examples of client/server network operating systems.

34 RANGKAIAN SETEMPAT Logikal Protokol TCP/IP AppleTalk Novell IPX XNS DECnet Banyan Vines page - 34