Computer Networking Fundamental –EC301
7/15/2011Computer NetworkingFundamental – EC301Introduction to NetworkingIntroduction to NetworkingBasic concepts and components ofcomputer networksNetworking StandardsPrinciples of communication innetworkingFunctions of Networking Hardware1
7/15/2011What is anetwork?Why we usenetwork?Network definitionA combination of computerhardware, cabling, network devices,and computer software usedtogether to allow computers tocommunicate with each other.Group of computers and otherdevices that are connected by sometype of transmission media.2
7/15/2011Why Use Networks? Using networks offersadvantages relative tousing a stand-alonecomputerComputer networkStand-alonecomputerThe advantages of networked computingrelative to standalone computing. Fewer Peripherals Needed– Many devices can be connected on anetwork. Increased Communication Capabilities– Networks provide several differentcollaboration tools that can be used tocommunicate between network users. Avoid File Duplication and Corruption– A server manages network resources.Servers store data and share it with users ona network.3
7/15/2011The advantages of networked computingrelative to standalone computing. Lower Cost Licensing– Application licensing can be expensivefor individual computers. Centralized Administration– Centralized administration reduces thenumber of people needed to manage thedevices and data on the network,reducing time and cost to the company. Conserve Resources– Data processing can be distributed acrossmany computers to prevent one computerfrom becoming overloaded withprocessing tasks.Fundamental types of networks Peer-to-peernetworks Client/servernetworks4
7/15/2011Peer-to-peer networks Every computer can communicatedirectly with every other computer By default, no computer has moreauthority than another Every computer is capable of sendingand receiving information to andfrom every other computerPeer-to-peer networks Advantages of a peer-to-peernetwork:– Less initial expense - No need for adedicated server.– Setup - An operating system (such asWindows XP) already in place may onlyneed to be reconfigured for peer-to-peeroperations. Disadvantages of a peer-to-peernetwork:– Decentralized - No central repository forfiles and applications.– Security - Does not provide the securityavailable on a client/server network.5
7/15/2011Client/server networks Server– central computer used to facilitatecommunication and resource sharingbetween other computers on the network(called clients) Client/server network– uses a server to enable clients to share data,data storage space, and devices To function as a server, a computer mustbe running a network operating system(NOS) Most of the concepts on the Network exam pertain to client/server networksClient/server networks Advantages of a client/servernetwork:– Centralized - Resources and data securityare controlled through the server.– Scalability - Any or all elements can bereplaced individually as needs increase.– Flexibility - New technology can be easilyintegrated into system.– Interoperability - All components(client/network/server) work together.– Accessibility - Server can be accessedremotely and across multiple platforms.6
7/15/2011Client/server networks Disadvantages of a client/servernetwork:– Expense - Requires initial investment indedicated server.– Maintenance - Large networks willrequire a staff to ensure efficientoperation.– Dependence - When server goes down,operations will cease across the network.The advantages Client/servernetworks over peer-to-peer networks User logon accounts and passwordscan be assigned in one place Access to multiple shared resourcescan be centrally granted to a singleuser or groups of users Problems can be tracked, diagnosed,and often fixed from one location7
7/15/2011The advantages Client/servernetworks over peer-to-peer networks Servers are optimized to handleheavy processing loads anddedicated to handling requests fromclients, enabling faster response time Because of their efficient processingand larger disk storage, servers canconnect more than a handful ofcomputers on a networkTheclassificationsof networksLANWANMAN8
7/15/2011Local area network (LAN) Confined to a relatively small space, such asa building or an office. Usually spans about 00-5kms and is generallya private network owned by anorganization. Each computer has the potential tocommunicate with any other computer ofthe network. High degree of interconnection betweencomputers Easy physical connection of computers in anetwork. Inexpensive medium of data transmission. High data transmission rate.Local area network (LAN)9
7/15/2011Metropolitan Area Network Larger than a LAN; connects clientsand servers from multiple buildings Is used to describe a network ofcomputers spanning a metropolitancity usually 5-50 kms of range. A company having multiple offices invarious parts of a city generally usesthis type of network. Example is the cellular or mobilephone network.Metropolitan Area Network10
7/15/2011Wide area network (WAN) Connects two or more geographicallydistinct LANs or MANs Communication facility Remote data entry Centralised information The transmission medium used isnormally telephone lines,microwaves and satellite links. Internet is an example of a wanWide area network (WAN)11
7/15/2011The differences between LAN andWANLANWAN Restricted to limitedgeographical area offew kilometres Devices are connectedwith wires and coaxialcables Cost of datatransmission in LAN isless The speed of datatransmission is muchhigher in LAN than inWAN. The speed variesfrom 0.1 to 100 mbps Few data transmissionerrors occur in LANcompared to WAN. Covers long distanceand operatesnationwide or evenworldwide Communication is donethrough telephonelines and satellite links Cost of datatransmission is veryhigh WAN the speed rangesfrom 1800 to 9600 bps. More data transmissionerrors occur in WANcompared to LAN.ClientWorkstationNetwork InterfaceCard (NIC)NetworkOperatingSystem (NOS)ServerNodeElementsCommon sionMediaConnectivitydevice12
7/15/2011Server A computer on the network thatmanages shared resources; serversusually have more processing power,memory, and hard disk space thanclients. They run network operatingsoftware that can manage not onlydata, but also users, groups, security,and applications on the network.Client A computer on the network thatrequests resources or services fromanother computer on a network; insome cases, a client could also act asa server. The term client may also refer to thehuman user of a client workstation orto client software installed on theworkstation.13
7/15/2011Workstation A personal computer (such as adesktop or laptop), which may ormay not be connected to a network;most clients are workstationcomputers.Host A computer that enables resourcesharing by other computers on thesame network14
7/15/2011Node A client, server, or other device thatcan communicate over a network andthat is identified by a uniquenumber, known as its networkaddress.Segment A part of a network. Usually, a segment is composed of agroup of nodes that use the samecommunications channel for all theirtraffic.15
7/15/2011Connectivity Device A specialized device that allowsmultiple networks or multiple partsof one network to connect andexchange data. A client/server network can operatewithout connectivity devices. However, medium- and large-sizedLANs use them to extend thenetwork and to connect with WANs.16
7/15/2011Topology The physical layout of a computernetwork. Topologies vary according to theneeds of the organization andavailable hardware and expertise. Networks can be arranged in a ring,bus, or star formation, and the starformation is the most common. Hybrid combinations of thesepatterns are also possible.17
7/15/2011Transmission Media The means through which data istransmitted and received. Transmission media may be physical,such as wire or cable, or atmospheric(wireless), such as radio waves.18
7/15/2011Network Interface Card The device inside a computer thatconnects a computer to the networkmedia, thus allowing it tocommunicate with other computers; Some connect to the motherboard,which is the main circuit thatcontrols the computer, some areintegrated as part of themotherboard, and others connect viaan external port. NICs are also known as networkadapters.19
7/15/2011Network Operating System The software that runs on a serverand enables the server to managedata, users, groups, security,applications, and other networkingfunctions. Examples include various types ofUNIX and Linux operating systems,Microsoft Windows Server 2003 orWindows Server 2008, and Mac OS XServer.20
7/15/2011Network Topology BusRingStarHybrid– Star Wired Bus– Star Wired Ring21
7/15/2011Bus In bus topology all workstations areconnected to a single communicationline called bus. In this type of network topologythere is no central server and all thecomputers can talk or communicateto all other systems connected to thecable. Transmission from any station travelsthe length of the bus in bothdirections and can be received by allworkstations.22
7/15/2011Ring In ring topology each station isattached to nearby stations on apoint-to-point basis so that the entiresystem is in the form of a ring. In this topology data is transmittedin one direction only. Thus the data packets circulate alongthe ring in either clockwise oranticlockwise direction.23
7/15/2011Star In star topology a number ofworkstations (or nodes) are directlylinked to a central server. Any communication betweenstations in a star LAN must passthrough the central server. There is bi-directionalcommunication between variousnodes. The central server controls all theactivities of the nodes.24
7/15/2011Hybrid A complex combination of the basictopologies is known as a hybridtopology. A hybrid is a combination of two ormore basic network topologies, suchas a star-bus, star-ring, or tieredtopology. In a hybrid topology, central anddistributed topologies are combinedto meet the needs of an organization.25
7/15/2011HybridStar Wired BusStar Wired Ring In a star-wiredbus topology,groups ofworkstations arestar-connectedto connectivitydevices and thennetworked via asingle bus, The star-wiredring topologyuses thephysical layoutof a star inconjunctionwith the ringlogical topology.Hybrid– Star Wired Bus – Star Wired Ring26
7/15/2011Network TopologiesBusAll devices are connected to a central cable, called the busor backbone. Bus networks are relatively inexpensive andeasy to install for small networks.All devices are connected to a central device, called a hub.Star networks are relatively easy to install and manage, butbottlenecks can occur because all data must pass throughthe hub.StarRingAll devices are connected to one another in the shape of aclosed loop, so that each device is connected directly to twoother devices, one on either side of it. Ring topologies arerelatively expensive and difficult to install, but they offerhigh bandwidth and can span large distances.Hybrid Groups of star-configured workstations are connected to alinear bus backbone cable, combining the characteristics ofthe bus and star topologies.1. ANSI2. EIA/TIA3. IEEE7. ICANNTheNetworkingStandards4. ISO6. ISOC5. ITU27
7/15/2011ANSI American National Standards Institute (ANSI)– Composed of more than a thousand representativesfrom industry and government– Represents United States in setting internationalstandards ANSI standards documents available:– ANSI’s Web site (www.ansi.org)– At university or public librariesEIA and TIA Electronic Industries Alliance (EIA): Tradeorganization composed of representatives fromelectronics manufacturing firms across US– Sets standards for its members– Helps write ANSI standards– Lobbies for legislation favorable to growth of computerand electronics industries Telecommunications Industry Association (TIA):Focuses on standards for informationtechnology (IT), wireless, satellite, fiber optics,and telephone equipment28
7/15/2011IEEE Institute of Electrical and Electronics Engineers International society composed of engineeringprofessionals Goals are to promote development andeducation in electrical engineering andcomputer science IEEE technical papers and standards are highlyrespected in the networking profession– Can purchase IEEE documents online from IEEE’s Website (www.ieee.org)ISO International Organization for Standardization Collection of organization standardsrepresenting 146 countries Goal is to establish international technologicalstandards to facilitate global exchange ofinformation and barrier-free trade Fewer than 300 of ISO’s more than 14,250standards apply to computer-related productsand functions29
7/15/2011ITU International Telecommunication Union Regulates international telecommunications:––––Radio and TV frequenciesSatellite and telephony specificationsNetworking infrastructureTariffs applied to global communications Typically, documents pertain more to globaltelecommunications issues than to industrytechnical specificationsISOC Internet Society Professional membership society that helps toestablish technical standards for the Internet Oversees groups with specific missions:– Internet Architecture Board (IAB): Technical advisorygroup of researchers and professionals Interested in overseeing Internet’s designand management– Internet Engineering Task Force (IETF): Sets standardsfor how systems communicate over the Internet How protocols operate and interact30
7/15/2011IANA and ICANN Internet Protocol (IP) addresses: Addresses usedto identify computers on the Internet and otherTCP/IP-based networks Internet Assigned Numbers Authority (IANA):Used to keep records of available and reserved IPaddresses and determines how addresses weredoled out– In 1997, coordinated efforts with three RegionalInternet Registries (RIRs) Not-for-profit agency that managesdistribution of IP addresses to private andpublic entitiesIANA and ICANN (continued) In late 1990s U.S. Department of Commerce(DOC) overhauled IP addressing and domainname management Internet Corporation for Assigned Names andNumbers (ICANN): Ultimately responsible for IPaddressing and domain name management– IANA still performs system administration Individuals and businesses lease addresses fromInternet Service Provider (ISP)– Business providing access to Internet and otherservices31
7/15/20113. Terminologies2. The rulesPrinciples ofcommunicationin networking1. BasicElements4. CommunicationproblemBasic Elements of a CommunicationSystemSourceChannelDestination32
7/15/2011Basic Elements of a CommunicationSystem Source– This device generates the data to betransmitted; examples are telephonesand personal computers. Channel– A medium that carries the message. Destination– The receiver (sink) who receives themessageRules of communicationsbetween two pointsComputerBased Device1TransmissionMediumComputerBased Device2 There are a number of phases that bothdevices must pass through in order toperform the common communicationsfunction of file transfer These phases ensure that the softwareon each device is structured to correct forerrors or inconsistencies from thecorresponding, remote device.33
7/15/2011Rules of communicationsbetween two points The rules for each of these phases areclearly defined by a protocol andtypical phases are as follows:––––––Establish a linkIssue a command and command qualifierAcknowledgment of commandDissection messagesError detection and correctionTermination of transmissionEstablish a link Device 1 checks to see if Device 2 is presenton the link by sending a specific "enquiry"message. If the link is active and device 2 is activethen it should respond by sending back an"acknowledgement" message. Device 1 must track the time that device 2takes to respond. If device 2 does not respond within a timeinterval (defined by the protocol) thendevice 1 assumes that the link is not active. This is called a transmission "time-out" error34
7/15/2011Issue a command and commandqualifier Device 1 sends device 2 a message, ina predefined format, which tellsdevice 2 that a file is to betransferred. As a qualifier within the message,device 1 tells device 2 what to dowith the file. For example, device 1may tell device 2 to place theincoming file onto disk storage, withthe file-name "FRED".Acknowledgment of command If device 2 has correctly received thecommand and qualifier from device 1,and is capable of carrying out thecommand, then it sends device 1 anacknowledgement message. The acknowledgement message tellsdevice 1 that it can now proceed withfurther action needed to fulfil thecommand. If device 2 is unable to act upon thecommand from device 1, then it mustrespond with an error message.35
7/15/2011Acknowledgment of command An error could occur on the receiver if,for example, the disk on which theincoming file is to be stored, is alreadyfull. The error response message would telldevice 1 that it should not proceedwith its proposed course of action.Dissection messages All messages, command andotherwise, must be broken down intopackets of manageable size fortransmission. Thus if an error should occur in apacket, then only that packet needsto be re-transmitted (and not theentire message). Therefore, when device 1 wishes totransfer a large file to device 2, thefile is broken up into packets andtransmitted packet by packet.36
7/15/2011Error detection and correction When device 1 sends a messagepacket to device 2, it performs amathematical calculation(manipulation) on every unit of datatransmitted. This calculation is transmitted todevice 2 immediately after themessage. Device 2 performs exactly the samemathematical calculation on itsincoming data as device 1.Error detection and correction Device 2 also reads in the calculation sent bydevice 1 and compares it with the localcalculation. If the two calculations providean identical result, then it is assumed thatthe incoming message was not corrupted onthe link. Device 2 can then issue a positiveacknowledgement to device 1 to indicatethat it is ready for the next message. If thetwo calculations are inconsistent, then it isassumed that incoming data has beencorrupted, and device 2 issues a "negativeacknowledgement" message to device 1,which indicates that the previous datamessage must be re-transmitted.37
7/15/2011Termination of transmission Device 1 transmits a file, piece-wise,ensuring that each packet is correctlyreceived by device 2, using the techniquedescribed in (Error Detection andCorrection). After the last piece of the file istransmitted to device 2 and positivelyacknowledged, then device 1 mustterminate the transmission. Device 1sends an "end of transmission" message todevice 2. This allows device 2 to close thestored file and return to other duties.Terminologies in relation tocommunication in networking Message Encoding– The effect of the skills, attitudes, andknowledge of the sender on the processof encoding the message. Message Formatting– A matter of agreement between twoparties as to the form of the data to beexchanged or transmitted. For example,both sides must use the same binary codefor characters.38
7/15/2011Terminologies in relation tocommunication in networking Message Size– the physical dimensions and proportionsof message. Message Timing– Includes speed matching and sequencingof message Message Patterns– Patterns of messages occur in two distinctforms: messages between objects, called aProtocol, and messages understood by aparticular kind of object, called anInterface.Communication problem Contract Pattern– Problem: How can behaviours be definedindependent of implementations? Correlation Identifier– Problem: In any messaging system, a consumermight send several message requests to differentservice providers. Message Sequence– Problem: Because of the inherent distributednature of messaging, communication generallyoccurs over a network. Message Expiration– Problem: Messages are stored on disk or persistentmedia. With the growing number of messages, diskspace is consumed.39
7/15/2011Networking HardwareTypes of network interface cardInstall and configure NIC hardware andsoftware.Functions of LAN connectivity hardware.Build simple peer-to-peer network usingTIA/EIA-568-a or TIA/EIA-568-b wiringstandard.Types Of Network Interface Card Cards on an expansion board inside acomputer (PCI NIC, PCI Express NIC).– It is used to connect Fast Ethernet Networkstogether and it is connected to a PCI Slot locatedon your computer's Motherboard Cards installed to the computer’s busexternally (PCMCIA adapter, USB port,FireWire, Compact Flash NIC)– PCMCIA (Personal Computer Memory CardInternational Association), USB (universal serialbus), CompactFlash, or FireWire (IEEE 1394) slotscan all be used to connect peripherals such asNICs. One advantage to externally attached NICsis their simple installation.40
7/15/2011Types Of Network Interface Card On-board NIC– A NIC that is integrated into a computer’smotherboard, rather than connected viaan expansion slot or peripheral bus.– Not all peripheral devices are connectedto a computer’s motherboard via anexpansion slot or peripheral bus.– Some are connected directly to themotherboard using on-board ports.– For example, the electrical connectionthat controls a computer’s mouseoperates through an on-board port, asdoes the connection for its keyboard andmonitor.Types Of Network Interface Card Wireless NIC– NICs are designed for use with eitherwired or wireless networks. WirelessNICs, which contain antennas to sendand receive signals.– One disadvantage to using wireless NICsis that currently they are somewhat moreexpensive than wire-bound NICs usingthe same bus type41
7/15/2011Functions of LAN connectivityhardware RepeaterHub / SwitchBridgesRoutersGatewaysRepeater Since a signal loses strength as itpasses along a cable, it is oftennecessary to boost the signal with adevice called a repeater. The repeater electrically amplifiesthe signal it receives andrebroadcasts it. Repeaters can be separate devices orthey can be incorporated into aconcentrator.42
7/15/2011Hub / Switch A concentrator is a device thatprovides a central connection pointfor cables from workstations, servers,and peripherals. In a star topology, twisted-pair wire isrun from each workstation to a centralswitch/hub. Most switches are active, that is theyelectrically amplify the signal as itmoves from one device to another.Hub / Switch Switches no longer broadcast networkpackets as hubs did in the past, theymemorize addressing of computersand send the information to thecorrect location directly.43
7/15/2011Bridges A bridge is a device that allows youto segment a large network into twosmaller, more efficient networks. If you are adding to an older wiringscheme and want the new networkto be up-to-date, a bridge canconnect the two. A bridge monitors the informationtraffic on both sides of the networkso that it can pass packets ofinformation to the correct location.Bridges Most bridges can "listen" to thenetwork and automatically figure outthe address of each computer onboth sides of the bridge. The bridge can inspect each messageand, if necessary, broadcast it on theother side of the network. The bridge manages the traffic tomaintain optimum performance onboth sides of the network44
7/15/2011Routers Router is intelligent device which routesdata to destination computers. It helps in connecting two different logicaland physical networks together. In small network server is connected torouter along with clients forcommunication. With routers network communication isnot possible; it is soul of network withoutwhich distribution if internet and othernetwork data to entire network areimpossible.Routers45
7/15/2011Gateways As name suggests it some kind ofpassing through to something.Interestingly gateways can besoftware or it can also be device. Gateway device connects LAN withinternet. Its basic functionality is toprovide security to the network. By using gateways incoming/outgoing traffic can be monitored forany malicious activity within thenetwork which can be harmful tonetwork integrity.46
7/15/201147
Fundamental –EC301 Introduction to Networking Introduction to Networking Basic concepts and components Basic concepts and components ooff . together to allow computers to communicate with each other. Group of computers and other devices that are
Dell EMC Networking S4148F-ON 2.2 Dell EMC Networking S4248FB-ON The Dell EMC Networking S4248FB-ON is a 1-RU, multilayer switch with forty 10GbE ports, two 40GbE ports, and six 10/25/40/50/100GbE ports. Two S4248FB-ON switches are used as leaf switches in the examples in this guide. Dell EMC Networking S4248FB-ON 2.3 Dell EMC Networking Z9100-ON
Networking Fundamentals » Volume 5, TCP/IP Networking Page 3 SECTIoN 2 Networking Models The OSI model and the TCP/IP model are the prevalent methods to describe the interdependency of networking protocols. Both of these are conceptual models only and simply describe, not prescribe how networking
Networking 101 . Agenda Introduction Networking Defined Purpose of Networking Types of Networking Meet & Greets Recap Disney Agenda . Did You Know? Approximately 70 percent of all jobs are found through networking Most people you meet have at least 250 contacts
Docker Networking with Linux Guillaume Urvoy-Keller Reference Scenario Basic tools: bridges, VETH Basic tools 2: Networking in namespaces Minilab : Anatomy of a docker container networking environment (45 min) Docker (host-level) Networking Docker Networking Model Docker Swarm Docker Network Overlay Sources documents Laurent Bernaille blog .
1.2 Advantages of computer networking Basically, Networking is a connection between two or more computers. The main purpose of a network is to share the information among different users. Figure 1.1 shows the networking of two computers: Fig 1.1 Computer in network Computer network consist of the following:
Module 7: Fundamental Analysis (NCFM Certification) 1. Introduction of Fundamental Analysis What is Fundamental & Technical Analysis? Difference between technical & fundamental analysis Features & benefits of Fundamental analysis 2. Top-Down Approach in Fundamental Analysis Economic Analysis Industry Analysis Company analysis 3.
On-line job searching networking does work. Sites like LinkedIn, Facebook, and a variety of other online networking websites can help you get in touch with other networkers at specific companies, with college affiliations or in a certain geographic area. 7. Attend networking events Networking in person works, too. If you belong to a
Screw-Pile in sand under compression loading (ignoring shaft resistance) calculated using Equation 1.5 is shown in Figure 3. The influence of submergence on the calculated ultimate capacity is also shown. The friction angle used in these calculations is the effective stress axisymmetric (triaxial compression) friction angle which is most appropriate for Screw-Piles and Helical Anchors. 8 .
