Chapter VChapter V

NETWORKNETWORKMr. Jesus F. Obenita Jr.Mr. Jesus F. Obenita Jr.

BBEMNHS ICT TeacherBBEMNHS ICT Teacher

NETWORKNETWORK

Are multiple computers linked Are multiple computers linked together to make simultaneous together to make simultaneous information sharing and exchange information sharing and exchange by multiple users.by multiple users.

Make it possible for its connected Make it possible for its connected user to share tools, resources and user to share tools, resources and information.information.

3 BASIC NETWORK 3 BASIC NETWORK CATEGORIESCATEGORIES

LOCAL AREA NETWORK LOCAL AREA NETWORK (LAN)(LAN)

METROPOLITAN AREA METROPOLITAN AREA NETWORK NETWORK (MAN)(MAN)

WIDE AREA NETWORK WIDE AREA NETWORK (WAN)(WAN)

LOCAL AREA NETWORK (LAN)LOCAL AREA NETWORK (LAN)

THE SMALLEST OF THE 3 THE SMALLEST OF THE 3 NETWORK TYPES, CONSIST OF NETWORK TYPES, CONSIST OF PCs CONNECTED TOGETHER PCs CONNECTED TOGETHER WITHIN A LIMITED AREA, SUCH WITHIN A LIMITED AREA, SUCH AS WITHIN THE SAME AS WITHIN THE SAME BUILDING, FLOOR OR BUILDING, FLOOR OR DEPARTMENT.DEPARTMENT.

METROPOLITAN AREA METROPOLITAN AREA NETWORK (MAN)NETWORK (MAN)

ARE NETWORK THAT ARE NETWORK THAT SPANS NO MORE THAN 50 SPANS NO MORE THAN 50 MILES. IT DESIGNED TO MILES. IT DESIGNED TO CONNECT LANs CONNECT LANs SPANNING A TOWN OR SPANNING A TOWN OR CITYCITY

WIDE AREA NETWORK (WAN)WIDE AREA NETWORK (WAN)

USED TO DISTRIBUTE USED TO DISTRIBUTE INFORMATION THOUSAND INFORMATION THOUSAND OF MILES AMONG OF MILES AMONG THOUSANDS OF USERS. THOUSANDS OF USERS.

IT SPANS CITIES, COUNTRIES IT SPANS CITIES, COUNTRIES EVEN CONTINENTS.EVEN CONTINENTS.

NETWORK NETWORK TERMSTERMS

NETWORK SERVERNETWORK SERVER

A POWERFUL COMPUTER WHOSE A POWERFUL COMPUTER WHOSE SOLE PURPOSE IS TO SERVE SOLE PURPOSE IS TO SERVE NETWORK CLIENTS.NETWORK CLIENTS.

SERVERS RUN NETWORK-SERVERS RUN NETWORK-CONTROLLING SOFTWARE AND CONTROLLING SOFTWARE AND PROVIDE WORKSTATIONS WITH PROVIDE WORKSTATIONS WITH REQUESTED RESOURCES.REQUESTED RESOURCES.

HOSTSHOSTS

ANY COMPUTER WHETHER ANY COMPUTER WHETHER MAINFRAME, SERVER, OR EVEN A MAINFRAME, SERVER, OR EVEN A PC THAT ACTS AS AN PC THAT ACTS AS AN INFORMATION SOURCE ON A INFORMATION SOURCE ON A NETWORK.NETWORK.

ANY COMPUTER THAT HAS A ANY COMPUTER THAT HAS A TCP/IP NETWORK ADDRESS CAN TCP/IP NETWORK ADDRESS CAN BE A HOST.BE A HOST.

PEERSPEERS

MEANS ANY COMPUTER SHARING MEANS ANY COMPUTER SHARING THE SAME PROTOCOL LAYER THE SAME PROTOCOL LAYER WITH ANOTHER COMPUTER.WITH ANOTHER COMPUTER.

WHEN TWO COMPUTERS SHARE WHEN TWO COMPUTERS SHARE RESOURCES SECURITY LEVELS RESOURCES SECURITY LEVELS AND USER GROUP, THEY ARE AND USER GROUP, THEY ARE CONSIDERED PEERS.CONSIDERED PEERS.

WORK STATIONWORK STATION

IS ANY NETWORK IS ANY NETWORK COMPUTER THAT COMPUTER THAT CONNECTS TO AND CONNECTS TO AND REQUEST RESOURCES REQUEST RESOURCES FROM A NETWORK.FROM A NETWORK.

PROTOCOLPROTOCOL

REFERS TO THE SPECIFIC REFERS TO THE SPECIFIC STANDARDS GOVERNING THE STANDARDS GOVERNING THE SENDING AND RECEIVING OF SENDING AND RECEIVING OF DATA.DATA.

DATA TRANSMISSION SYSTEM DATA TRANSMISSION SYSTEM FOLLOW PREDETERMINED RULES FOLLOW PREDETERMINED RULES SO DATA TRAVELS N SO DATA TRAVELS N UNIVERSALLY ACCEPTED UNIVERSALLY ACCEPTED MANNER.MANNER.

2 TYPES OF NETWORK 2 TYPES OF NETWORK ARCHITECTUREARCHITECTURE

PEER TO PEER PEER TO PEER NETWORKNETWORK

CLIENT /SERVER CLIENT /SERVER NETWORKNETWORK

PEER TO PEER NETWORKPEER TO PEER NETWORK

PEER TO PEER NETWORK- no PEER TO PEER NETWORK- no centralized computer oversees the centralized computer oversees the networks, no server, and computers networks, no server, and computers simply connect with each other in a simply connect with each other in a work group to share files, printers, work group to share files, printers, and internet access. Networking and internet access. Networking equipment: NIC, Cables and network equipment: NIC, Cables and network hub.hub.

CLIENT/SERVER NETWORKCLIENT/SERVER NETWORK

USE A NETWORK OPERATING USE A NETWORK OPERATING SYSTEM TO MANAGE THE SYSTEM TO MANAGE THE ENTIRE NETWORK. THERE IS ENTIRE NETWORK. THERE IS USUALLY AN USUALLY AN NT DOMAIN NT DOMAIN CONTROLLERCONTROLLER, WHICH ALL , WHICH ALL THE COMPUTERS LOG ON TO.THE COMPUTERS LOG ON TO.

NETWORK MEDIANETWORK MEDIA

EXAMPLE OF NETWORK EXAMPLE OF NETWORK MEDIAMEDIA

UTP UTP (UPSHIELDED TWISTED PAIR)(UPSHIELDED TWISTED PAIR)

COAXIAL CABLECOAXIAL CABLE FIBER OPTICSFIBER OPTICS STP STP (SHIELDED TWISTED PAIR)(SHIELDED TWISTED PAIR)

UTP UTP (UNSHIELDED TWISTED PAIR)(UNSHIELDED TWISTED PAIR)

The least expensive and most popular The least expensive and most popular network media. One of the network media. One of the advantages is its special coating that advantages is its special coating that shrinks in high fire temperatures, shrinks in high fire temperatures, eliminating toxic fumes emissions. eliminating toxic fumes emissions.

A UTP disadvantage is its lack A UTP disadvantage is its lack insulation, which makes the cable insulation, which makes the cable susceptible to electrical interference.susceptible to electrical interference.

STP (Shielded Twisted Pair)STP (Shielded Twisted Pair)

Is twisted, plastic coated, shealth-Is twisted, plastic coated, shealth-wrapped copper wire. The main wrapped copper wire. The main difference between UTP and STP difference between UTP and STP is the STP’s aluminum or polyester is the STP’s aluminum or polyester shielding surrounding individual shielding surrounding individual wires.Shielding allows STP to wires.Shielding allows STP to reduce or eliminate interference.reduce or eliminate interference.

FIBER OPTIC CABLESFIBER OPTIC CABLES

Are thin, glass strand that carry light Are thin, glass strand that carry light waves and are wrapped by an outer waves and are wrapped by an outer protective sheath. Interpreted by protective sheath. Interpreted by computer as data, the light waves in a computer as data, the light waves in a fiber optic can travel great distances and fiber optic can travel great distances and deliver vast amounts of data. Fiber optic deliver vast amounts of data. Fiber optic cabling system are extremely powerful cabling system are extremely powerful and efficient but they are also quite and efficient but they are also quite expensive.expensive.

COAXIAL CABLESCOAXIAL CABLES

Are commonly used by cable TV Are commonly used by cable TV companies. A center cable insulated by companies. A center cable insulated by plastic or foam, wrapped in a copper mesh plastic or foam, wrapped in a copper mesh wire and sheathed in a plastic or rubber wire and sheathed in a plastic or rubber jacket.jacket.

Coaxial cable is relatively inexpensive to Coaxial cable is relatively inexpensive to produce and install.produce and install.

It is useful when connecting a small number It is useful when connecting a small number of computers using pre-existing hardware, of computers using pre-existing hardware, or when sharing small amount of data.or when sharing small amount of data.

NETWORK NETWORK HARDWAREHARDWARE

NETWORK INTERFACE CARD NETWORK INTERFACE CARD (NIC)(NIC)

A PRINTED CIRCUIT BOARD, AN ADAPTER A PRINTED CIRCUIT BOARD, AN ADAPTER THAT PLUGS INTO THE COMPUTER’S THAT PLUGS INTO THE COMPUTER’S MOTHERBOARD WHEN CONNECTED WITH MOTHERBOARD WHEN CONNECTED WITH A CABLE NETWORK, PROVIDES THE A CABLE NETWORK, PROVIDES THE PHYSICAL LINK BETWEEN YOUR PHYSICAL LINK BETWEEN YOUR COMPUTER AND THE NETWORK.COMPUTER AND THE NETWORK.

ITS MAIN FUNCTION IS TO CONVERT ITS MAIN FUNCTION IS TO CONVERT DATA INTO CABLE-TRANSMITTABLE DATA INTO CABLE-TRANSMITTABLE DATA, AND PROVIDE A CONNECTION TO DATA, AND PROVIDE A CONNECTION TO NETWORK MEDIANETWORK MEDIA

NETWORK HUBNETWORK HUB

A HARDWARE DEVICE THAT ALL PCs A HARDWARE DEVICE THAT ALL PCs ON A NETWORK ARE CONNECTED TO ON A NETWORK ARE CONNECTED TO BY CABLING. THE HUB MANAGES BY CABLING. THE HUB MANAGES RECEIVING AND TRANSMOTTING RECEIVING AND TRANSMOTTING DATA FROM NETWORKED DEVICES. IT DATA FROM NETWORKED DEVICES. IT ALLOWS DATA TO FLOW ON AND OFF ALLOWS DATA TO FLOW ON AND OFF THE NETWORK BETWEEN PRINTERS, THE NETWORK BETWEEN PRINTERS, COMPUTERS, AND OTHER DEVICES BY COMPUTERS, AND OTHER DEVICES BY SHARING THE LANES TRAFFIC.SHARING THE LANES TRAFFIC.

REPEATERREPEATER

A DEVICE THAT STRENGTHEN SIGNALS A DEVICE THAT STRENGTHEN SIGNALS AND ALLOW THEN TO STAY CLEAR AND ALLOW THEN TO STAY CLEAR OVER LONGER DISTANCES.OVER LONGER DISTANCES.

NETWORK BRIDGENETWORK BRIDGE

DEVIDES NETWORK INTO SMALLER, MORE DEVIDES NETWORK INTO SMALLER, MORE MANAGEABLE SECTIONS HELPING REDUCE MANAGEABLE SECTIONS HELPING REDUCE NETWORK TRAFFIC.NETWORK TRAFFIC.

DATA SIGNALS ARRIVING AT A BRIDGE DATA SIGNALS ARRIVING AT A BRIDGE CONTAIN INFORMATION ABOUT THEIR CONTAIN INFORMATION ABOUT THEIR DESTINATIONS. THE NETWORK BRIDGE DESTINATIONS. THE NETWORK BRIDGE ALLOWS ONLY SPECIFIC INFORMATION TO ALLOWS ONLY SPECIFIC INFORMATION TO TRAVEL OVER A CERTAIN PATHS. WHEN TRAVEL OVER A CERTAIN PATHS. WHEN SIGNAL ARRIVING AT A BRIDGE DOES NOT SIGNAL ARRIVING AT A BRIDGE DOES NOT POSSE THE APPROPRIATE ADDRESS IT IS POSSE THE APPROPRIATE ADDRESS IT IS FILTERED OUT COMPLETELY.FILTERED OUT COMPLETELY.

NETWORK SWITCHNETWORK SWITCH

BRIDGES MAKE A SIMPLE DO/DON’T BRIDGES MAKE A SIMPLE DO/DON’T DECISION ON WHICH PACKETS TO DECISION ON WHICH PACKETS TO SEND ACROSS TWO SEGMENTS THEY SEND ACROSS TWO SEGMENTS THEY CONNECT. IT HELPS DETERMINE HOW CONNECT. IT HELPS DETERMINE HOW DATA MOVES OVER VERY LARGE DATA MOVES OVER VERY LARGE NETWORKS. IT WORKS LIKE A NETWORKS. IT WORKS LIKE A STOPLIGHT AT A BUSY INTERSECTION. STOPLIGHT AT A BUSY INTERSECTION. IT ALLOWS DATA TO TRAVEL IN ITS IT ALLOWS DATA TO TRAVEL IN ITS OWN LANE OF TRAFFIC.OWN LANE OF TRAFFIC.

ROUTERROUTER

A DEVICE THAT FORWARDS DATA A DEVICE THAT FORWARDS DATA PACKETS BETWEEN LOCAL OR WIDE PACKETS BETWEEN LOCAL OR WIDE AREA NETWORK GROUPS. USING AREA NETWORK GROUPS. USING ROUTING TABLES AND PROTOCOLS, ROUTING TABLES AND PROTOCOLS, ROUTERS READ A SIGNAL’S NETWORK ROUTERS READ A SIGNAL’S NETWORK ADDRESS AND DECIDE ITS MOST ADDRESS AND DECIDE ITS MOST EXPEDIENT ROUTE.EXPEDIENT ROUTE.