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NETWORKING. Er.Narinder Singh Dhindsa Senior Lecturer, GPCG Patiala. Networking. Connecting two or more computers in such a way that they can share softwares and hardwares is called Networking. Networking enables a group of computers to share information, hardware and software application.
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NETWORKING Er.Narinder Singh Dhindsa Senior Lecturer, GPCG Patiala. Punjab EDUSAT Society(PES)
Networking • Connecting two or more computers in such a way that they can share softwares and hardwares is called Networking. • Networking enables a group of computers to share information, hardware and software application. • Networking can be connection oriented or connection less. Punjab EDUSAT Society(PES)
Network connection • The hardware must be compatible. • The software setup must be in a way so that communicating computers must understand each other. • There must be a proper cabling or signaling method to connect all the computers in the group. Punjab EDUSAT Society(PES)
Network Topology The design or architecture used to lay down a computer network is called Network Topology. Some common Topologies are:- • Star topology. • Ring topology. • Bus topology… Punjab EDUSAT Society(PES)
Types of network Networking can be broadly categorized as following: • LAN : Local Area Network. • MAN: Metropolitan Area Network. • WAN: Wide Area Network. Punjab EDUSAT Society(PES)
Connectivity • Connectivity is the unbiased transport of packets between two end points or computers in a network. • To provide connectivity internet protocol is used on most of the networks. • In case of connectivity problems, the communication and transmission between two ends is stopped. Punjab EDUSAT Society(PES)
Connectivity • The connectivity refers to the degree to which any given computer can cooperate with other components. • Various softwares and hardware components are used to provide connectivity. • Connectivity is checked by ping command. Punjab EDUSAT Society(PES)
Hardware for Networks • Hardware components of networking are: • Network interface card(NIC). • Hubs,Bridges and Switches. • Modems. • Routers. • Gateways. • Repeaters etc. Punjab EDUSAT Society(PES)
Network Interface Card • NIC is a expansion card which works with the network operating system to control the flow of information over the network. • It uses a special circuitry on it to perform the conversion of signals according to the requirement of the transmission media. • NIC consists of chips and traces and it translates electric pulses into light, infrared or other robust pulses. Punjab EDUSAT Society(PES)
Network Interface Card • NIC provides the PC with a method of sending data to and receiving data from other systems by connecting the PC to the network cabling structure. • NIC’s automatically detect and adjust to the speed of the network without any configuration. • These are called autosending NICs. Punjab EDUSAT Society(PES)
Network Interface Card • The NIC are also called network adaptors. • While connecting NICs in a network their installation and configuring is very important for proper installation of NIC. • The three necessary phases for the NICs to pass through are as following 1) Setting , 2) Configuring , 3) Interfacing. Punjab EDUSAT Society(PES)
Setting • Before connecting a NIC in a network, it needs a setting of certain parameters like IRQ, I/O address, DMA, shared memory address, etc. • These settings are done according to the need of the network and a proper combination of them is required before connecting the network card. Punjab EDUSAT Society(PES)
Configuring • The configuring involves both hardware and software configuring. • The hardware configuration needs the configuring of jumpers and DIP switches. • For software configuration of NICs, a software is used that is already stored in CMDS. Punjab EDUSAT Society(PES)
Interfacing • Once the settings of parameters and configuring of card is done, it is ready for interfacing. • After the proper connection, its driver is installed. • The standard drivers are Network Device Interface Specification(NDIS) and open Data link interface(OM). Punjab EDUSAT Society(PES)
HUBS • Hub is a special device which is used to extend a network by allowing additional workstations in the network. • Types of hubs: 1) Active Hubs. 2) Passive Hubs. 3) Intelligent Hubs. Punjab EDUSAT Society(PES)
Hubs • Active hubs are those devices that amplify the transmission signals in addition to extending cable lengths and ports. • Active hubs are only used to extend lengths of cables and ports in order to provide connection between workstations at long stations. Punjab EDUSAT Society(PES)
Hubs • Passive hubs also allow additional work stations to be added in the network. • They split the transmission signal which results in loss of strength of signal. • Weak signals cannot go long distances. • Star network uses passive hubs and active hubs are used by cable operators and internet service provider. Punjab EDUSAT Society(PES)
Intelligent Hubs • These hubs have a special kind of software in them to perform management function in the network. • The software provides them capability to detect and isolate the problems. • It is beneficial in big networks as manual detection of the problem is tedious. Punjab EDUSAT Society(PES)
Need of a hub • Hub is useful in star topologies as the central computer was just a connecting device. • It was difficult to make a number of connections to a single computer. • All network cables come to central location so it is easier to maintain and trouble shoot the large network. Punjab EDUSAT Society(PES)
Connecting a hub(Star) PC PC HUB PC PC Punjab EDUSAT Society(PES)
Connecting a Hub • Different types of networks use different hubs. • Star network uses a central hub that controls all network devices. • In hub cascading, a master hub is used along with many slave hubs. • The master hub remains at the highest level of hierarchy. Punjab EDUSAT Society(PES)
Cascaded Hub Master hub Hub Hub Hub PC PC PC PC Hub Hub PC PC PC PC Punjab EDUSAT Society(PES)
Connecting a Hub • The third type of hub connection is backbone connection. • A backbone connection is like a cascading hub without a master hub. • All the hubs at level one are connected to a coax backbone through their AUI ports. • A thick coax backbone can support as many as 100 hubs. Punjab EDUSAT Society(PES)
BACKBONE HUB HUB HUB HUB PC HUB PC PC PC Punjab EDUSAT Society(PES)
Hub capacity • Hub capacity means the number of connections that can be made by a hub. • The capacity also varies depending on the type of network. • The maximum number of PC connections to a hub is 1024 but it is an exaggerated number. • Most hubs come with 8,16 & 24 ports. Punjab EDUSAT Society(PES)
Bridges • Bridges are used to connect two sub networks which use identical protocols. • It connects two LANs to form an extended LAN. • Bridges operate at the Data Link Layer of OSI model while router operates at network layer. • They read physical address of source & destination for delivery of data packets. Punjab EDUSAT Society(PES)
Bridges • A bridge performs three basic functions which are as following:- • Examining and learning the address of the nodes. • Frame filtering, reformatting, and forwarding of frames of data. • Routing the frames. Punjab EDUSAT Society(PES)
Switches • It is a hardware device that filters and forwards packets between LAN segments. • Switches monitor the traffic constantly that comes across them. • They reroute and provide a efficient path. • They can investigate the packets and calculate the address of their destination before forwarding them. Punjab EDUSAT Society(PES)
Switches • Switches provide dedicated bandwidth at each node so that traffic passing through one node doesn’t affect other nodes. • It contains intelligence to turn on or off a specific port through its software controls. • Switches also operate at data link layer of the OSI model so it can connect the LAN segment of different configurations. Punjab EDUSAT Society(PES)
TCP/IP • TCP/IP is the abbreviation for transmission control protocol/ internet protocol. • It is a set of communications protocol. • It contains set and procedures for dealing with packet transport, media access, session communication, file transfer, email and terminal emulation. Punjab EDUSAT Society(PES)
TCP/IP • It has no official model like OSI but its functions can be as following:- • Physical layer. • Network access layer. • Internet layer. • Host to Host or transport layer. • Application layer. Punjab EDUSAT Society(PES)
Physical layer of TCP/IP • The physical layer covers the physical interface between data transmission device and a transmission medium. • It specifies the characteristics of transmission medium like type of connectors, type of signals, bit rate, frequency, etc. • It is the lowest layer of the model. Punjab EDUSAT Society(PES)
Network Access Layer(TCP/IP) • The data exchange between end system and network is managed by this layer. • It provides various functions like addressing, routing, priority sequencing and security etc. • It is a software layer. • The type of software used depends on the type of network . Punjab EDUSAT Society(PES)
Internet Layer(TCP/IP) • When different networks are attached, different functions and procedures are required . • These functions are provided by the internet layer, the third layer. • In this layer, the internet protocol provides routing functions across multiple networks. • IP is implemented in end systems & routers. Punjab EDUSAT Society(PES)
Transport Layer(TCP/IP) • The fourth layer provides an ordered and reliable delivery of data. • It uses transmission control protocol(TCP). • It provides a connection oriented service. • TCP has the mechanism for reliable transmission of data frames between two end systems. • The mechanism is independent of the nature of the application. Punjab EDUSAT Society(PES)
Application Layer(TCP/IP) • The topmost layer contains the logic required to support user applications. • It provides functions like file transfer, data base management, etc. • The transport and application layer protocols are known as end to end protocols. • The various protocols are SMTP, Telnet, FTP, etc. Punjab EDUSAT Society(PES)
Addressing • When one application wants to connect to another an address is required. • Addressing in TCP/IP can be categorized in as following:- • Physical Addressing. • Logical Addressing. • IP addressing. Punjab EDUSAT Society(PES)
Physical Addressing • The address assigned to a NIC by administrator is called Physical address. • Physical addresses are of three types:- • Unicast address. • Multicast address. • Broadcast address. Punjab EDUSAT Society(PES)
Unicast address • Unicast address are permanently assigned to the NIC and are unique for a machine. • It is an identifier for an interface. • The card monitors the transmissions and matches them against this address to identify the frames assigned to it. • This monitoring helps the host. Punjab EDUSAT Society(PES)
Multicast Address • It is a logical identifier for a group of hosts in a computer network. • To receive a datagram they identify a group of stations in the same domain. • The host computers set the NICs to accept specific multicast address. • This technique is effective if common information is to be communicated to a group of hosts. Punjab EDUSAT Society(PES)
Broadcast Address • A broadcast address is one in which all bits in the host portion of the IP address have been set to 1. • All datagrams sent by TCP/IP maybe received by all machines on a subnet. • Broadcast address is a logical address at which all devices connected to a MAC network are enabled to receive datagrams. Punjab EDUSAT Society(PES)
Logical Addressing • Logical address is an address at which an item appears to reside from the perspective of an executing program. • It maybe different from physical address. • A logical address is used to request info from a controller, which in turn converts the logical address to a physical address to get information from a storage location. Punjab EDUSAT Society(PES)
IP Addressing • IP address is a unique identifier of a computer on a TCP/IP networks and on the internet. • Every IP address consists of 32 bits and a binary system of 0s and 1s. • There are five classes of IP addresses and its format contains three fields:- (1) Class type, (2) network id, (3) host id. Punjab EDUSAT Society(PES)
Classes of IP addresses • Class A : Class A addresses are specified to networks with large number of hosts. It uses one byte(8 bits) to identify class type and 3 bytes to identify host id numbers. The first bit is set to 0 and the network number values range from 1 to 127. 8 bits 3 bytes Punjab EDUSAT Society(PES)
Classes of IP addresses • Class B: Class B accommodate a lesser number of networks by providing 2 bytes to identify host id numbers. • Other two byte are used for class type and network id type. The first two bits are always 10 and the network number begins from 128 to 191. 2 bytes of network id 2 bytes for host id Punjab EDUSAT Society(PES)
Classes of IP addresses • Class C: Class C addresses use three bytes to identify the class type and network id number. • Only one byte is used for host id number. The address starts with 110 and its range is from 192 to 223. Network id Host id Punjab EDUSAT Society(PES)
Classes of IP addresses • Class D networks are reserved for multicast addresses. • The binary addresses start with 1110 and IP address range can be between 224 to 239. • Class E are reserved for future use. • Its addresses will start with 1111 and the range will be from 240 to 255. Punjab EDUSAT Society(PES)
THANK YOU E-mail id : narinder.dhindsa@gmail.com Punjab EDUSAT Society(PES)