BA 471 – Telecommunications and NetworkingOutlineSome Basic Characteristics of Effective Human CommunicationSome Basic Characteristics of Telecommunication NetworksWired Transmission MediaWireless TransmissionNetwork Design How to support full connectivity?Network Design Find an economic internetworking solutionSome Network Design Issues Major Cost ComponentsNetwork Design Management How to design a feasible and economical internetwork?Example 1Slide 12Slide 13Theoretical Framework: 5-layer network modelProtocols and addresses used at different layers of the 5-layer network modelSlide 16Application and Transport LayersNetwork LayerNetwork Layer (Continued)Data Link LayerPhysical LayerBA 471 – Telecommunications and NetworkingDr. V.T. RajaOregon State [email protected] presented in Dr. Marshall’s BA471 class, Winter 2006Outline•Introduction–Analogy with effective human communication•5-layer Network ModelA theoretical framework for our day-to-day interactions on the InternetSome Basic Characteristics of Effective Human Communication•Sender/Receiver•Messages (Words)•Transmission MediaAir/Printed Page•Less noisy room (or) talk loud enough•Speak same language or have an InterpreterSome Basic Characteristics of Telecommunication Networks•Source; Destination – Host•Signals (Digital/Analog) –Modulation (digital to analog)–Demodulation (analog to digital)–Done by a Modem•Transmission Media–(Wired/Wireless)•Communications Protocols/StandardsWired Transmission Media•Coaxial (like cable TV)•Twisted Pair–Copper–Shielded and twisted to reduce noise•Fiber Optic–Much faster–Able to go longer distances without a repeater–Uses light not electricity–Multi-color lights vastly increases capacity–ExpensiveWireless Transmission•Infrared (as in a TV remote)•Radio Signals (as in microwave transmissions)•Satellites–http://www.orbitaldebris.jsc.nasa.gov/index.html–GEOS: Geosynchronous Earth Orbiting Satellites – stationary orbit at 22,300 miles above the Earth–LEOS: Low Earth Orbiting Satellites–Closer to the Earth and reachable from mobile devices–200-1,000 miles above the Earth–Not stationary, goes around the Earth in about 90 minutes–60-70 LEOS are needed to cover the EarthNetwork DesignHow to support full connectivity?Design the most economic internetwork Design the most economic internetwork between “end-user nodes” and an existingbetween “end-user nodes” and an existing WAN (Wide Area network e.g. the Internet)WAN (Wide Area network e.g. the Internet)UsernodeUsernodeUsernodeUsernode UsernodeUsernodeUsernodeUsernodeUsernodeUsernodeWANNetwork DesignFind an economic internetworking solutionUsernodeUsernodeUsernodeUsernodeUsernodeUsernodeA direct connection toa WAN backbone nodeUsernodeUsernodeUsernodeUsernodeUsernodeUsernodeConnection viamultiplexersSome Network Design IssuesMajor Cost ComponentsAcquisition and installation costs of a MUXAcquisition and installation costs of a MUXCost of high bandwidth link between MUX Cost of high bandwidth link between MUX and WAN (Internet)and WAN (Internet)Cost of low bandwidth link between end-Cost of low bandwidth link between end-user node and MUXuser node and MUXA Multiplexer (MUX) consolidates several (many?) slow links A Multiplexer (MUX) consolidates several (many?) slow links (local networks or single nodes) connecting them to a fast link (local networks or single nodes) connecting them to a fast link (e.g. a WAN such as the Internet).(e.g. a WAN such as the Internet).Network Design ManagementHow to design a feasible and economical internetwork?Find an optimal number of MUXs to interconnect all Find an optimal number of MUXs to interconnect all given user nodes to some existing WAN such that ... given user nodes to some existing WAN such that ... All user nodes are connectedAll user nodes are connected User communication requirements are satisfiedUser communication requirements are satisfied Capacity constraints on each MUX is not violatedCapacity constraints on each MUX is not violated Total internetworking costs are minimizedTotal internetworking costs are minimized Topology issues are consideredTopology issues are consideredExample 1Example 2Example 3Theoretical Framework: 5-layer network model•Application Layer (Layer-5)•Transport Layer•Network Layer•Data Link Layer•Physical Layer (Layer-1)Protocols and addresses used at different layers of the 5-layer network model•HTTP (Hyper Text Transfer Protocol) operates at the Application Layer. – Example of an application layer address: www.bus.oregonstate.edu •TCP (Transmission Control Protocol) operates at the Transport Layer.–Example of a transport layer default port address/port ID: 80 (Web); 25(E-mail)Protocols and addresses used at different layers of the 5-layer network model•IP (Internet Protocol) operates at the Network Layer. –Example of an IP address: 128.192.64.224•Ethernet operates at the data link layer. –Example of a DLL address: 00-B0-D0-B4-54-13Application and Transport Layers•User interfaces with application software using: –Application layer (e.g., web/e-mail) address•Transport layer’s major function is:–Packetizing•Breaking large messages into smaller packets at source •Reassembling packets at final destination•Creates/appends TCP header–Packet #–Source/Destination Port IDNetwork Layer•Major functions of IP at network layer are –Addressing and –Routing •IP prepares IP header which contains:–Source/Destination IP Address and–Routing InformationNetwork Layer (Continued)•Addressing–DHCP (Dynamic Host Control Protocol) Server•Assigns IP addresses to client machines requesting an IP address–DNS (Domain Name Service) Server•Similar to directory assistance – used for finding destination IP addresses. •Routing–Routing tables; Routers (Tracert); Routing ProtocolsData Link Layer•Major functions of Data Link Layer are:–Media Access Control •Handling message collisions–Error Detection–Error Correction–Message Delineation •Identifying beginning and ending of packets – since all computer transmissions go out as 0s and 1s over the physical layer •DL layer appends a DL header and DL TrailerPhysical Layer•Wired Media/Wireless Media: Examples–Twisted pair; Coaxial; Fiber Optic Cables–Microwave; Satellites and Cell phones•Internetworking Devices:
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