1Local Area NetworksSchool of BusinessEastern Illinois University © Abdou Illia, Fall 2014(October 20, 2014)2Learning ObjectivesUnderstand LAN Servers functionsUnderstand common LAN standards3LAN: DefinitionA communication network that interconnects networking devices within a small geographical area using broadcast system.Networking devices include: Computers, Printers, Print Server devices, File Servers, Modems, etc.Q: How many ports for the switch / hub?Different than Point-to-Point transmission system used in WAN24Servers Common services:File ServiceInternet web serviceEmail serviceFile transfer servicePrint serviceSpecial network services–Autoconfiguration service–Domain name service–Remote Access Service–Internet Connection sharing5Selecting a serverSingle server Versus Multiple specialized Servers–Decision based on Cost, Optimization, Reliability, and SecurityOptimization: –File servers need storage capacity and rapid access–Client/Server applications need very fast processors6Print ServiceA Print Server device is basically: NIC + a parallel or USB port + Random Access Memory + Intelligence to receive data and commands from print queue manager program.Note: Possible to connect printer directly to file server, but people might have to walk far to get their printout.Network printers have built-in NIC & print server hardware. Therefore no need for external print server device.37LAN MAC protocolsToken Ring–For LANs that use physical star topology (with MAU) and logical ring topology –Offered at speeds of 4 and 16 Mbps.–More expensive components than CSMA/CD–Losing ground quickly to CSMA/CDEthernet or CSMA/CD–Most common form of LAN today.–Star-wired bus topology using hub/switch is most common –Many standards (form 10Base2 to Gigabit Ethernet)Two major types of LANRule for effective communicationAll networking devices must use same MAC protocol: All Ethernet hubs/switches and Ethernet NICs OR All Token Ring MAUs and Token Ring NICsCommunications cannot take place if different MAC protocols are being used.Ethernet Hub/switchEthernet NICToken Ring NICMAUEthernet NICToken Ring NIC8Ethernet (IEEE 802.3) standardshttp://grouper.ieee.org/groups/802/index.htmlhttp://standards.ieee.org/getieee802/802.3.html802.3CSMA/CD802.3Ethernet802.3uFast Ethernet802.3zGigabit Ethernet10Base-210Base-510Base-T10Broad-36……100Base-TX100Base-FX100Base-T4……1000Base-SX1000Base-LX1000Base-CX1000Base-T……802.3-200510 Gigabit Ethernet10GBase-T10GBase-CX410GBase-SR10GBase-LX4……9Ethernet standardsQ: If a LAN is described as 10BaseT, list everything you know about that network.Rules for effective communications:All networking devices must use same MAC protocol: All Ethernet hubs/switches and Ethernet NICs OR All Token Ring MAUs and Token NICsDevices should operate at same speed. Example 10BaseT NIC and 10BaseT hub.NICs, Central collection points (hub, switch, MAU), and other internetworking devices should be compatible with the transmission media used.410- Speed: 10 Mbps- Signal type: Baseband w coaxial cable- Distance: 185 meters/segment- Physical bus topology & logical bus topology- No more than 30 nodes (computers, printers, etc.) per segment- Nodes must be spaced at least 0.5 meters apart10Base2 and 10Base5 Ethernet10Base5Speed:10 MbpsSignal type:Baseband transmissionDistance:500 meters10Base2Speed:10 MbpsSignal type:Baseband transmissionDistance:185 meters10Base2- Speed: 10 Mbps- Signal type: Baseband w coax. cable- Distance: 500 meters/segment-Physical bus topology & logical bus topology- No more than 100 nodes per segment-Nodes must be spaced at least 2.5 meters intervals10Base511- Speed: 10 Mbps- Signal type: Baseband- Distance: 100 meters between the Hub/Switch and the node- No more than 1024 nodes per Hub/Switch- Physical star topology, logical bus topology- Uses 2-pair of wire CAT3 UTP with RJ-45 connectors10BaseT Ethernet10BaseTSpeed:10 MbpsSignal type:Baseband transmissionMedium:Twisted pair12- Speed: 100 Mbps- Signal type: Baseband- Distance: 100 meters between the Hub/Switch and the node- Topology: Physical star, logical bus using 100BaseTXcollection points- Uses two-pair CAT5 or better UTP with RJ-45 connectors100BaseTX Ethernet100BaseTXSpeed:100 MbpsSignal type:Baseband transmissionMedium:Twisted pair513- Speed: 100 Mbps- Signal type: Baseband- Distance: Up to 2 kilometers between sender & receiver- Topology: Physical star, logical bus using 100BaseFX collectionpoints- Uses multi-mode long wavelength fiber optics with lasers as lightsources 100BaseFX Ethernet100BaseFXSpeed:100 MbpsSignal type:Baseband transmissionMedium:Fiber Optic100BaseSX same as 100BaseFX, but uses less expensive short wavelength fiber optics with light-emitting diode (LED) and is limited to 300 m distance 14LAN systems and standardsFDDI (Fiber Distributed Data Interface)–Uses Token passing method–Designed for transmission at 100 Mbps using Optical fiber–Possible interconnection of 500 stations–Allows for two concentric ringsThe primary ring offers 100 Mbps data rateSecondary ring for backup or for additional 100 Mbps data rateInner ringOuter ring15Summary Questions1)What are the four factors to take into account in deciding how many servers to use to implement a LAN’s services?Answer: Optimization, reliability, security, cost2)To what two devices does a print server device connect? Answer: To a printer via a parallel or USB cable and to a hub/switch via conducted media like UTP3)In print service using a print server device, where does a print job go when it leaves the client PC (not counting the hub or switch)? Answer: The print job first goes to a file server, which puts it in a print queue. 4)Do you have to use special printers for print service?Answer: You do not need special printers, because any printer with a parallel or USB cable could be connected to the network using a print server device. Network printers come with integrated NIC. They can be used without a print server device.616Summary QuestionsYour organization has 12 employees, each with his or her own stand-alone PC running Windows XP. Each computer has a 10 Mbps NIC that could work with coaxial cable or twisted pair (see next slide) a) List all the additional hardware you would have to buy in order to install a 100BaseTX LAN. Make very sure that you list all the things the organization will have to buy. The organization