Communication Using a Network

1. Communication Using a Network Chapter 7

2. Chapter Objectives • State and explain the different components of a network • Explain and install Network Interface Card • Describe the basic principles of data communication • Explain the use of MAC address • Explain the concepts of a direct cable connection • Identify and troubleshoot problems of NIC Jetking Infotrain Ltd.

3. Recall • Fiber Distributed Data Interface (FDDI) provides high-performance and connects multiple stations at the data transfer rate of 100 Mbps. • The two types of logical topologies are: • Token ring logical topology • Token bus logical topology • Asynchronous Transfer Mode (ATM) is a network protocol which converts data traffic into a stream of fixed size cell before transmission. • The basic network components of AppleTalk are: Sockets, Nodes, Network and Zones. Jetking Infotrain Ltd.

4. Data Communication • Transmission of information between two computers or nodes Jetking Infotrain Ltd.

5. Network Interface Card (NIC) - I • Hardware device used to connect different computers on Network • Serves as a link for sending and receiving data on a network • MAC address is address assigned by IEEE to identify network card Jetking Infotrain Ltd.

6. Network Interface Card (NIC) - II • Operates at layer 2 of the OSI model • Supports data transfer rate of 10, 100 or 1000 Mbps • User can select an NIC depending on the type of network, protocol and media used • MAC address is stored on the PROM of the NIC Jetking Infotrain Ltd.

7. Ethernet Card • Used in devices which are connected using Ethernet technology • Two types of Ethernet network card – Wired and wireless • A wireless Ethernet card can not communicate with a wired Ethernet card and vice-versa • Different types of Ethernet cards can be used depending on the type of network and corresponding connector that is required Jetking Infotrain Ltd.

8. Lights on NIC and hub • Different LEDs on NIC: • Link LED • ACT LED • Speed LED • Collision LED • LEDs on Hub: • Power LED • Port LED Jetking Infotrain Ltd.

9. Different LEDs on a NIC • Link LED – Used to indicate whether any network connection is present or not • Act LED – If this LED flashes it indicates that some activity is taking place on the network • Speed LED – ON state indicates that it operates at 100 Mbps and off for 10 Mbps • Collision LED – Glows when a collision takes place and present on some old NICs Jetking Infotrain Ltd.

10. MAC Address • Also known as hardware or physical address • Used to identify nodes at lower levels of the OSI model • MAC address assigned by IEEE • Is a 12 digit hexadecimal number (48 bit address) Jetking Infotrain Ltd.

11. Show the structure of MAC address from CBT Jetking Infotrain Ltd.

12. Frame Structure • A MAC frame is divided into 4 parts • A maximum of 1500 bytes of data can be sent in a frame • CRC is only 4 bytes long Jetking Infotrain Ltd.

13. Show Installing NIC from CBT Jetking Infotrain Ltd.

14. Direct Cable Connection • One device acts as a host and other acts as a guest • Can also use infrared connection, if both nodes have required hardware • All the latest versions of windows provide a software which allows a user to have a direct serial-to-serial, parallel-to-parallel, or infrared-to-infrared connection with the other PC. • To establish a connection using serial ports, a cable known as null modem is used • Connection speed of serial data cable connection is very slow but it’s a cheaper option when NICs are not available Jetking Infotrain Ltd.

15. Diagnostic and repair show from CBT Jetking Infotrain Ltd.

16. Case Study The Bangalore branch of MoneyMaker bank is organizing a seminar on the various developments that have occurred in the past one year. David has created a presentation for this purpose which is stored on the network server. This file can be accessed only through David's system. But on the day of seminar, he is unable to access the system. Jetking Infotrain Ltd.

17. Problem Unable to access the file which is available on network server Jetking Infotrain Ltd.

18. Solution • Verify cable connection • Verify LED status of NIC • Verify LED status of hub • The LED on NIC should be ON, once you boot the operating system Jetking Infotrain Ltd.

19. Summary – I • The main components of data communication are sender, receiver, medium and message • The data to be sent is converted into signals and then transmitted over the network • Signaling techniques are of two types – broadband and baseband • Baseband signals transmit data at a single frequency • Broadband technique can transmit data using more than one frequency Jetking Infotrain Ltd.

20. Summary – II • Network Interface Cards are devices that are used to get connected to different computers on a network • Some examples of NIC are Ethernet Card and Token Ring Card • Ethernet cards support transfer rate of 10 or 100 or 1000 Mbps • MAC address is a hardware address that is embedded onto the NIC • Lower layers of OSI model identify nodes on the network by their MAC address Jetking Infotrain Ltd.

21. Summary – III • A connection established between two nodes by directly connecting a cable is known as direct cable connection. • Signals lying on the cable are absorbed by the terminators at the end of the cable to avoid collision. • Cross over cables can be used for temporary connection between two devices when switch or hub is not present. • Volt-ohm meters is a cable-testing tool which is used to troubleshoot the network cabling. Jetking Infotrain Ltd.

22. Summary – IV • Volt-ohm meter is used to measures voltage and resistance and to check the continuity of a cable. • Tone generator and probe is another troubleshooting tool which has the ability to identify wires, finding open circuits and short circuits, diagnosing crosstalk and other telecom tasks Jetking Infotrain Ltd.