Slide Title,Body Text,Second Level,Third Level,Fourth Level,Fifth Level,2007 Cisco Systems,Inc.All rights reserved.,ICND1 v1.01-,*,Building a Simple Network,Exploring the Functions of Networking,Building a Simple NetworkExplo,What Is a Network?,What Is a Network?,Common Physical Components of a Network,Common Physical Components of,Interpreting a Network Diagram,Interpreting a Network Diagram,Resource-Sharing Functions and Benefits,Data and applications,Resources,Network storage,Backup devices,Resource-Sharing Functions and,Network User Applications,E-mail(Outlook,POP3,Yahoo,and so on),Web browser(IE,Firefox,and so on),Instant messaging(Yahoo IM,Microsoft Messenger,and so on),Collaboration(Whiteboard,Netmeeting,WebEx,and so on),Databases(file servers),Network User ApplicationsE-mai,Impact of User Applications on the Network,Batch applications,FTP,TFTP,inventory updates,No direct human interaction,Bandwidth important,but not critical,Interactive applications,Inventory inquiries,database updates.,Human-to-machine interaction.,Because a human is waiting for a response,response time is important but not critical,unless the wait becomes excessive.,Real-time applications,VoIP,video,Human-to-human interaction,End-to-end latency critical,Impact of User Applications on,Characteristics of a Network,Speed,Cost,Security,Availability,Scalability,Reliability,Topology,Characteristics of a NetworkSp,Physical Topology Categories,Physical Topology Categories,Logical Topologies,Logical Topologies,Bus Topology,All devices receive the signal.,Bus TopologyAll devices receiv,Star Topology,Transmission through a central point.,Single point of failure.,Star TopologyTransmission thro,Extended-Star Topology,More resilient than star topology.,Extended-Star TopologyMore res,Ring Topology,Signals travel around ring.,Single point of failure.,Ring TopologySignals travel ar,Dual-Ring Topology,Signals travel in opposite directions.,More resilient than single ring.,Dual-Ring TopologySignals trav,Full-Mesh Topology,Highly fault-tolerant,Expensive to implement,Full-Mesh TopologyHighly fault,Partial-Mesh Topology,Trade-off between fault tolerance and cost,Partial-Mesh TopologyTrade-off,Connection to the Internet,Connection to the Internet,Summary,A network is a connected collection of devices that can communicate with each other.Networks carry data in many kinds of environments,including homes,small businesses,and large enterprises.,There are four major categories of physical components in a computer network:the computer,interconnections,switches,and routers.,Networks are depicted graphically using a set of standard icons.,The major resources that are shared in a computer network include data and applications,peripherals,storage devices,and backup devices.,The most common network user applications include e-mail,web browsers,instant messaging,collaboration,and databases.,User applications affect the network by consuming network resources.,SummaryA network is a connecte,The ways in which networks can be described include characteristics that address network performance and structure:,speed,cost,security,availability,scalability,reliability,and,topology.,A physical topology describes the layout for wiring the physical devices,while a logical topology describes how information flows through a network.,In a physical bus topology,a single cable effectively connects all the devices.,In a physical star topology,each device in the network is connected to the central device with its own cable.,When a star network is expanded to include additional networking devices that are connected to the main networking device,it is called an extended-star topology.,Summary(Cont.),The ways in which networks can,Summary(Cont.),In a ring topology,all the hosts are connected in the form of a ring or circle.In a dual-ring topology,there are two rings to provide redundancy in the network.,A full-mesh topology connects all devices to each other;in a partial-mesh topology,at least one device has multiple connections to all other devices.,There are three common methods of connecting the small office to the Internet:DSL using the existing telephone lines,cable using the CATV infrastructure,and serial links using the classic digital local loops.,Summary(Cont.)In a ring topol,CCNA12网络的功能和网络拓扑结构课件,