Cisco Networking Academy Program: Engineering Journal and Workbook, Volume I, Second Edition Engineering Journal and Workbook Questions and Answers Chapter Computer Basics Introduction It is important to be able to recognize and name the major components of a PC for the following three reasons: • Computers are important network-building devices • Many networking devices are themselves special-purpose computers, with many of the same parts as “normal” PCs • For you to view the online curriculum, your own computer must be in working order, which means that you might need to occasionally troubleshoot simple problems in your computer’s hardware and software Concept Questions Demonstrate your knowledge of these concepts by answering the questions in the Engineering Journal space provided • The transistor and the integrated circuit made modern computers possible Explain why The invention of a semiconductor transistor opened up many possibilities for making smaller, more reliable computers Millions of transistors can now be placed on one small piece of semiconductor Further microminiaturization of integrated circuits leads to widespread use of PCs in homes and businesses • If your computer doesn’t power up, what steps might you take to identify and correct the problem? If your computer does not power up as expected, consider verifying the following: ⇒ ⇒ Power switch is switched to the on (1) position ⇒ - 239 Power cord is plugged into wall socket Motherboard power inlet is securely fastened Engineering Journal and Workbook, Vol I, nd Ed – Chapter Copyright © 2002 Cisco Systems, Inc • Explain how to the following: ⇒ Select the NIC card The network card selection should involve consideration of the following: • • Network topology (bus, ring, star) • Medium type (UTP, STP, 10Base2, 10Base5, 10BaseF) • ⇒ Bus type (PCI, ISA, EISA, and so on) Transport speed (1 Mbps, Mbps, 10 Mbps, 16 Mbps, 100 Mbps, 1000 Mbps) Set the correct IP address The IP address selected should be on the same network or subnetwork as the other devices that need to be accessed This should be a unique address that is not currently being used by any other nodes on the local network ⇒ Adjust the display (if necessary) The display can easily be changed by selecting the display icon from the control panel Select the setting option and choose the desired resolution and color depth Click Apply to reflect changes ⇒ Install and set up the browser Use the installer program to install and configure your browser Once installed, add any necessary browser plug-ins such as Flash or Shockwave Choose your method of connectivity, usually dialup or localarea network (LAN) The first connection attempt after install will invoke the Internet Wizard Utility Vocabulary Exercise Chapter Define the following terms as completely as you can Use the online Chapter or the Cisco Systems Networking Academy: First-Year Companion Guide, Second Edition, material for help ASCII (American Standard Code for Information Interchange) bits plus parity) for character representation An 8-bit code (7 Backplane Physical connection between an interface processor or card and the data buses and power distribution buses inside a Cisco chassis Backplane components Backplane, interface, mouse port, network card, parallel port, and other miscellaneous ports Binary The binary number system, or Base 2, is made up entirely of 0s and 1s Computers use Base to express IP addresses - 239 Engineering Journal and Workbook, Vol I, nd Ed – Chapter Copyright © 2002 Cisco Systems, Inc Bits Each variable set by a computer is represented as being a or a These 0s and 1s represent a circuit being open or closed, or a capacitor being charged or uncharged Each and is said to be a bit Bus A collection of wires through which data is transmitted from one part of a computer to another It connects all the internal computer components to the CPU The Industry Standard Architecture (ISA) and the Peripheral Component Interconnect (PCI) are two types of buses Bytes Term used to refer to a series of consecutive binary digits that are operated upon as a unit (for example, an 8-bit byte) Capacitor A capacitor consists of two conducting metal plates separated by an insulating material Capacitors store energy in the form of electrostatic fields CD-ROM drive A compact disk read-only memory drive; a device that can read information from a CD-ROM Central processing unit (CPU) The part of a computer that controls all the other parts It fetches instructions from memory and decodes them This action may cause it to transfer data to or from memory or to activate peripherals to perform input or output Expansion slots An opening in a computer where a circuit board can be inserted to add new capabilities to the computer Floppy disk drive A disk drive that can read and write to floppy disks, usually in the ½” 1.44 MB or ¼” 1.2 MB format Hard disk drive The device that reads and writes data on a hard disk Two main types of drive interfaces are current in today’s computers: the Integrated Drive Electronics (IDE) drive and the Small Computer System Interface (SCSI; pronounced scuzzy) drive Usually referred to by interface type and capacity (MB or GB; for example, 10 GB SCSI drive) Integrated circuit (IC) A device made of semiconductor material; it contains many transistors and performs a specific task Light emitting diodes (LEDs) A semiconductor device that emits light when a current passes through it Status lights on hardware devices are typically LEDs Local-area network (LAN) LANs consist of computers, network interface cards, networking media, network traffic control devices, and peripheral devices in a single building or geographically limited area LANs make it possible for businesses that use computer technology to efficiently share items, such as files and printers, and to make communications such as e-mail possible They tie together data, communications, computing, and file servers Microprocessor A silicon chip that contains a CPU Monitor connector The part of a video cable that plugs into a port or an interface SVGA connectors are typically a 15-pin connector Motherboard Mouse port - 239 The main printed circuit board of a microcomputer A port designed to connect a mouse to a PC Engineering Journal and Workbook, Vol I, nd Ed – Chapter Copyright © 2002 Cisco Systems, Inc Network 1) Collection of computers, printers, routers, switches, and other devices that are able to communicate with each other over some transmission medium 2) Command that assigns a NIC-based address to which the router is directly connected 3) Command that specifies any directly connected networks to be included Network card 1) An expansion board inserted into a computer so that the computer can be connected to a network 2) Board that provides network communication capabilities to and from a computer system Also called an adapter NIC (network interface card) Also called a LAN adapter, it plugs into a motherboard and provides a port to connect to the network A NIC communicates with the network through a serial connection, and with the computer through a parallel connection Each card requires an IRQ, an I/O address, and an upper memory address to work with DOS or Windows 95/98 An interrupt request line (IRQ) is a signal informing a CPU that an event that needs its attention has occurred Parallel port An interface capable of transferring more than one bit simultaneously It is used to connect external devices, such as printers PC components Components found within a personal computer include the motherboard, video card, network adapter, hard drive, CPU, memory, sound card, CDROM drive, floppy drive, and power supply Personal computer subsystems Subsystems of a personal computer include the system bus, CD-ROM drive, CPU, expansion cards, expansion slots, floppy disk drive, hard disk drive, motherboard, and power supply Power cord A cord used to connect an electrical device to an electrical outlet to provide power to the device Power supply The component that supplies power to a computer Printed circuit boards (PCBs) A thin plate on which chips (integrated circuits) and other electronic components are placed Protocol 1) Formal description of a set of rules and conventions that govern how devices on a network exchange information 2) Field within an IP datagram that indicates the upper layer (Layer 4) protocol sending the datagram Random-access memory (RAM) Also known as read-write memory, RAM can have new data written into it and stored data read from it A drawback of RAM is that it requires electrical power to maintain data storage Resistor A device made of a material that opposes the flow of electric current Read-only memory (ROM) the microprocessor Nonvolatile memory that can be read, but not written, by Serial port An interface that can be used for serial communication in which only one bit is transmitted at a time Small, discrete components Components that are usually found in a laptop These components are smaller—the expansion slots become PCMCIA or PC slots, where NICs, modems, hard drives, and other useful devices, usually the size of a thick credit card, can be inserted into the PCMCIA slots along the perimeter Solder A conductor that is made up a mixture of lead (Pb) and tin (Sn), and water with ions - 239 Engineering Journal and Workbook, Vol I, nd Ed – Chapter Copyright © 2002 Cisco Systems, Inc An expansion card that handles all sound functions Sound card System unit The main part of a PC; the system unit includes the chassis, the microprocessor, the main memory, the bus, and the ports It does not include the keyboard or the monitor, or any external devices connected to the computer Throughput Rate of information arriving at, and possibly passing through, a particular point in a network system Transistor A device that amplifies a signal or opens and closes a circuit Video card A board that plugs into a PC to give it display capabilities Wide-area networks (WANs) Data communications networks that serve users across a broad geographic area and often use transmission devices provided by common carriers Frame Relay, SMDS, and X.25 are examples of WAN technologies Focus Questions What are the major components of a PC? Components found within a personal computer include the motherboard, video card, network adapter, hard drive, CPU, memory, sound card, CD-ROM drive, floppy drive, power supply What is the information flow in an idealized computer? Boot instructions—Stored in ROM until they are sent out Software applications—Stored in RAM after they are loaded RAM and ROM—Constantly talk to the CPU through the bus Application information—Stored in RAM while applications are being used Saved information—Flows from RAM to some form of storage device Exported information—Flows from RAM and the CPU, through the bus and expansion slots, to the printer, the video card, the sound card, or the network card What is the relationship of NICs to PCs? The NIC enables hosts to connect to the network and is, therefore, considered a key network component Compare PC components with laptop components The main difference is that components in a laptop are smaller—the expansion slots become PCMCIA or PC slots, where NICs, modems, hard drives, and other useful devices, usually the size of a thick credit card can be inserted into the PCMCIA slots along the perimeter - 239 Engineering Journal and Workbook, Vol I, nd Ed – Chapter Copyright © 2002 Cisco Systems, Inc What is data throughput and how does it relate to digital bandwidth? Throughput refers to the actual, measured bandwidth, at a specific time of day, using specific Internet routes, while downloading a specific file The throughput is often far less than the maximum possible digital bandwidth of the medium that is being used Why are there different bandwidths? Some factors that determine throughput and bandwidth include the following: Internetworking devices Type of data being transferred Topology Number of users User’s computer Server computer Power- and weather-induced outages Congestion What units measure the quantity of information? The most basic unit of information is the bit The basic unit of time is the second If you want to describe the amount of information flow in a specific period of time, you could use the units “bits per second” to describe this flow How binary numbers represent alphanumeric data? Alphanumeric characters are converted to data that can travel across the internetwork The data is put into a packet or a datagram that contains a network header with source and destination logical addresses These addresses help network devices send the packets across the network along a dynamically chosen path Each network device must put the packet into a frame The frame includes a header with the physical address of the next directly connected device in the path The frame must be converted into a pattern of 1s and 0s (bits) for transmission on the medium (usually a wire) - 239 Engineering Journal and Workbook, Vol I, nd Ed – Chapter Copyright © 2002 Cisco Systems, Inc CCNA Exam Review Questions The following questions help you review for the CCNA exam Answers also appear in Appendix A, “Answers to the CCNA Exam Review Questions,” of the Cisco Networking Academy Program: Engineering Journal and Workbook, Volume I, Second Edition Which of the following best defines networking? a b A connection of computers, printers, and other devices for the purpose of communication c A set of rules governing how computer workstations exchange information d A set of rules or procedures that are either widely used or officially specified A device connected to a computer to provide auxiliary functions What is a connection of computers, printers, and other devices for the purpose of communication? a b Network c Mainframe d Peripheral Protocol Which of the following terms is used in computing to refer to physical parts or equipment? a b Software c Protocol d Hardware Network Which of the following terms is used in computing to refer to programs or applications? a b Software c Peripheral d - 239 Hardware Network Engineering Journal and Workbook, Vol I, nd Ed – Chapter Copyright © 2002 Cisco Systems, Inc Which of the following refers to devices connected to a computer to provide auxiliary functions such as printing, added disk space, scanning, or CD-ROM? a b Software c Peripheral d Protocol Network Why are individual PCs not efficient or cost effective for business applications? a b It is difficult for businesses to communicate quickly or efficiently using individual PCs c It is difficult to provide management for operating individual PCs d Individual PC use requires businesses to duplicate equipment and resources All of the above What is a standalone computer? a b A computer that shares files and printers with other computers c A computer that operates independently from other computers d A computer that manages data efficiently A computer that has a different operating system What kind of computer operates independently from other computers? a b PC c Mac d Mainframe Standalone Why did standalone computers become an inefficient and ineffective way for businesses to operate? a b It was difficult to communicate quickly or efficiently using standalone computers c It was difficult to provide management for operating standalone computers d - 239 Businesses had to duplicate equipment and resources All of the above Engineering Journal and Workbook, Vol I, nd Ed – Chapter Copyright © 2002 Cisco Systems, Inc 10 What does the term protocol mean in computing terms? a b A universal translator that allows different kinds of computers to share data c A description of a set of rules and conventions that govern how devices on a network exchange information d 11 A tool that allows Macintosh and PC computers communicate with each other The language that all the computers on a network must use to communicate with each other Which of the following best defines protocol? a b A device connected to a computer to provide auxiliary functions c A group of people who are assigned to work as a team d 12 A formal description of a set of rules and conventions The connection of computers, printers, routers and switches What is a formal description of a set of rules and conventions called? a b Protocol c Standard d 13 Peripheral Network Why are protocols important? a b By consolidating the industry, they save companies money c By forming electronic islands, they bypass the sneaker net d 14 By setting rules, they allow different types of computers to talk to each other By using common carriers, they manage data efficiently What must all computers on a network be able to for the network to operate properly? a b Connect to a telephone line c Use CD-ROMs d - 239 Print to a local printer Speak the same language Engineering Journal and Workbook, Vol I, nd Ed – Chapter Copyright © 2002 Cisco Systems, Inc 48 After a network topology change, what routing protocol characteristic reduces incorrect or wasteful routing decisions? a b Convergence c Equivalence d 49 Symmetry Correspondence What is a routing loop? a b A network path that is circular and has no branches c A packet that cycles repeatedly through a constant series of network nodes d 50 A route to often requested destinations A process that routers go through when performing self-diagnostics What is the process called where packets never reach their destination, but instead cycle repeatedly through the same series of network nodes? a b End-to-end messaging c Convergence d 51 Split horizon Routing loop Why routing loops occur? a b Split horizons are artificially created c Network segments fail catastrophically and take other network segments down in a cascade effect d 52 Slow convergence after a modification to the internetwork Default routes were never established and initiated by the network administrator Why routing loops occur? a b A network device fails and that information is slowly passed to all the routers in the internetwork c Default routes were never established and initiated by the network administrator d 225 - 239 Split horizons are artificially created Network segments fail catastrophically and take other network segments down in a cascade effect Engineering Journal and Workbook, Vol I, nd Ed – Chapter 25 Copyright © 2002 Cisco Systems, Inc 53 Why does the problem of counting to infinity occur? a b Noncongruence c Slow convergence d 54 Split horizon Router inequivalence Which best describes the count-to-infinity problem? a b Packets cycle repeatedly through a constant series of network nodes c During heavy traffic periods, freak collisions can occur and damage the packet headers d 55 Routers continuously increment the hop count as a routing loop proceeds After a split horizon occurs, two sets of metrics exist for the same destination and neither matches that in the routing table How can the count-to-infinity problem be prevented? a b By invoking a split horizon process c By tracking network traffic levels and regulating flow d 56 By forcing a routing loop By imposing an arbitrary hop-count limit How can the count-to-infinity problem be solved? a b Define infinity as some maximum number c Switch from distance-vector to link-state mode d 57 Initiate a routing loop Force a router convergence and reconciliation What happens when the hop-count exceeds the maximum in a routing loop? a b The default route is recalled and used c The network is considered unreachable, and the loop ends d 226 - 239 The loop ends and the data packet is returned to the source for retransmission later A count to infinity is initiated, and a split horizon invoked Engineering Journal and Workbook, Vol I, nd Ed – Chapter 25 Copyright © 2002 Cisco Systems, Inc 58 How can the count to infinity problem be prevented? a b By using split horizon routing systems c By increasing router memory d 59 By using routing loops By using hold-down timers Which best describes hold-down timers? a b Time during which messages are held if network segment is temporarily unavailable c Time allowed before intervention to halt routing loop d 60 Timer that synchronizes the router table update process Time during which routers will neither send nor receive updated routing tables Why are hold-down timers useful? a b They force all routers in a segment to synchronize switching operations c They reduce the amount of network traffic during high traffic periods d 61 They flush bad information about a route from all routers in the network They provide a mechanism for bypassing failed sections of network When are routers placed in a hold-down state? a b When a link in a route fails c When a routing table becomes corrupted d 62 When a routing loop occurs When convergence occurs too slowly How does a hold-down timer work? a b When the hop count exceeds a fixed value, the hold-down timer holds the message until a split horizon is established c When a router receives an update indicating that a network is now inaccessible, the router marks the route and starts a hold-down timer d 227 - 239 By holding messages in routing loops for a given time period, the holddown timer reduces network traffic at peak times When a count is started, a hold-down timer is started too; if after a given time period the count continues, the timer halts the process and returns control to the nearest router Engineering Journal and Workbook, Vol I, nd Ed – Chapter 25 Copyright © 2002 Cisco Systems, Inc 63 What are the major two link-state concerns? a b Processing and memory requirements c Routing loops and equivalence d 64 Split horizons and convergence Table copying and counting to infinity Which of the following best describes link-state advertisement (LSA)? a b Broadcast message relaying state of data links (up or down) to all routers c Broadcast packet that contains information about neighbors and path costs d 65 Broadcast message in response to a convergence call Broadcast packet that is initiated by an active routing loop What are LSAs used for? a b To determine path metrics c To broadcast convergence calls d 66 To halt routing loops To maintain routing tables of receiving routers What is the most complex and important aspect of link-state routing? a b Ensuring that convergence occurs rapidly c Avoiding routing loops during initial start up d 67 Making sure all routers get all the necessary LSA packets Providing mechanisms for split horizons and count to infinity avoidance What will happen if routers have different sets of LSAs? a b Routes become unreachable because routers disagree about a link c A master comparison is forced and subsequent convergence on a single routing table occurs d 228 - 239 A check sum procedure is initiated and faulty routing tables repaired A broadcast message is sent with the master copy of the routing table to all routers Engineering Journal and Workbook, Vol I, nd Ed – Chapter 25 Copyright © 2002 Cisco Systems, Inc 68 What is one problem with link-state updating? a b Routers can become unreachable because they don’t have a complete picture of the internetwork c In synchronizing large networks, it is difficult to tell which updates are correct d 69 Easy to start a routing loop and subsequent count to infinity If the master routing table is corrupted, the entire network will go down What is one problem with link-state updating? a b Easy to start a routing loop and subsequent count to infinity c If the master routing table is corrupted, the entire network will go down d 70 Routers can become unreachable because they don’t have a complete picture of the internetwork Order of router startup alters the topology learned Which of the following is correct? a b Distance-vector routing develops a map of the network; whereas, linkstate routing gets topological data from the routing tables of their neighbors c Distance-vector routing requires lots of bandwidth and network overhead; whereas, link-state routing requires considerably less d 71 Distance-vector routing gets all topological data from the routing tables of their neighbors; whereas, link-state routing develops a map of the network by accumulating LSAs Distance-vector routing has quick convergence time; whereas, link-state routing has a slow convergence time and is therefore prone to routing loops Which of the following is correct? a b Distance-vector routing determines the best path by adding to the metric value it receives; whereas, link-state routing has the routers calculating their own shortest path to destinations c Distance-vector routing has quick convergence time; whereas, link-state routing has a slow convergence time and is therefore prone to routing loops d 229 - 239 Distance-vector routing requires lots of bandwidth and network overhead; whereas, link-state routing requires considerably less Distance-vector routing has the routers calculate their own shortest path to destinations; whereas, link-state routing determines the best path by adding to the metric value it receives from its neighbors Engineering Journal and Workbook, Vol I, nd Ed – Chapter 25 Copyright © 2002 Cisco Systems, Inc 72 Which of the following is correct? a b Distance-vector routing requires lots of bandwidth and network overhead; whereas, link-state routing requires considerably less c Distance-vector routing updates for topology changes with periodic table updates; whereas, link-state routing updates are triggered by topology changes d 73 Distance-vector routing has a quick convergence time; whereas, linkstate routing has a slow convergence time and is therefore prone to routing loops Distance-vector routing updates are triggered by topology changes; whereas, link-state routing updates for topology changes with periodic scheduled table updates Which best describes hybrid routing? a b Uses distance-vector routing to determine best paths between topology during high-traffic periods c Uses topology to determine best paths but does frequent routing table updates d 230 - 239 Uses distance vectors to determine best paths, but topology changes trigger routing table updates Uses topology to determine best paths but uses distance vectors to circumvent inactive network links Engineering Journal and Workbook, Vol I, nd Ed – Chapter 25 Copyright © 2002 Cisco Systems, Inc Chapter 26 Routing Protocols Introduction After testing the hardware and loading the Cisco IOS system image, the router finds and applies the configuration statements These entries provide the router with details about router-specific attributes, protocol functions, and interface addresses If the router faces a beginning condition where the router is unable to locate a valid startup-config file, however, it enters an initial router configuration mode called the setup mode With the setup-mode command facility, you can answer questions in the system configuration dialog This facility prompts you for basic configuration information The answers you enter enable the router to use a sufficient, but minimal, feature router configuration, which includes the following: • An inventory of interfaces • An opportunity to enter global parameters • An opportunity to enter interface parameters • A setup script review • An opportunity to indicate whether you want the router to use this configuration After you approve setup-mode entries, the router uses the entries as a running configuration The router also stores the configuration in NVRAM as a new startupconfig You can start using the router For additional protocol and interface changes, use the enable mode and enter the command configure Concept Questions Demonstrate your knowledge of these concepts by answering the following questions in the space provided • Routers can be configured to use one or more IP routing protocols Identify and briefly explain the different IP routing protocols At the Internet layer of the TCP/IP suite of protocols, a router can use an IP routing protocol to accomplish routing through the implementation of a specific routing algorithm Examples of IP routing protocols include the following: RIP—A distance-vector routing protocol IGRP—Cisco’s distance-vector routing protocol OSPF—A link-state routing protocol EIGRP—A balanced hybrid routing protocol 231 - 239 Engineering Journal and Workbook, Vol I, nd Ed – Chapter 26 Copyright © 2002 Cisco Systems, Inc • Two IP routing protocols are RIP and IGRP Compare and contrast these two IP routing protocols RIP was originally specified in RFC 1058 Its key characteristics include the following: It is a distance-vector routing protocol Hop count is used as the metric for path selection (see Figure 26-8) If the hop count is greater than 15, the packet is discarded By default, routing updates are broadcast every 30 seconds IGRP is a distance-vector routing protocol developed by Cisco IGRP sends routing updates at 90-second intervals, advertising networks for a particular autonomous system Some of the IGRP key design characteristics emphasize the following: Versatility that enables it to automatically handle indefinite, complex topologies Flexibility for segments that have different bandwidth and delay characteristics Scalability for functioning in very large networks Vocabulary Exercise Chapter 26 Define the following terms as completely as you can Use the online Chapter 26 or the Cisco Systems Networking Academy: First-Year Companion Guide, Second Edition material for help Autonomous system Collection of networks under a common administration sharing a common routing strategy Autonomous systems are subdivided by areas An autonomous system must be assigned a unique 16-bit number by the IANA Sometimes abbreviated AS Bandwidth The difference between the highest and lowest frequencies available for network signals The term is also used to describe the rated throughput capacity of a given network medium or protocol Delay The time between the initiation of a transaction by a sender and the first response received by the sender Also, the time required to move a packet from source to destination over a given path Distance-vector routing algorithm Class of routing algorithms that iterate on the number of hops in a route to find a shortest-path spanning tree Distance-vector routing algorithms call for each router to send its entire routing table in each update, but only to its neighbors Distance-vector routing algorithms can be prone to routing loops, but are computationally simpler than link-state routing algorithms Also called Bellman-Ford routing algorithm Dynamic routing Routing that adjusts automatically to network topology or traffic changes Also called adaptive routing Enhanced IGRP (EIGRP) Advanced version of IGRP developed by Cisco Provides superior convergence properties and operating efficiency, and combines the advantages of link-state protocols with those of distance-vector protocols Compare with IGRP 232 - 239 Engineering Journal and Workbook, Vol I, nd Ed – Chapter 26 Copyright © 2002 Cisco Systems, Inc IGRP (Interior Gateway Routing Protocol) IGP developed by Cisco to address the problems associated with routing in large, heterogeneous networks Compare with EIGRP See also IGP, OSPF, and RIP Link-state routing algorithm Routing algorithm in which each router broadcasts or multicasts information regarding the cost of reaching each of its neighbors to all nodes in the internetwork Link-state algorithms create a consistent view of the network and are therefore not prone to routing loops, but they achieve this at the cost of relatively greater computational difficulty and more widespread traffic (compared with distancevector routing algorithms) MTU ( maximum transmission unit) interface can handle Maximum packet size, in bytes that a particular OSPF (Open Shortest Path First) Link-state, hierarchical IGP routing algorithm proposed as a successor to RIP in the Internet community OSPF features include leastcost routing, multipath routing, and load balancing OSPF was derived from an early version of the IS-IS protocol Reliability Ratio of expected to received keepalives from a link If the ratio is high, the line is reliable Used as a routing metric RIP (Routing Information Protocol) IGP supplied with UNIX BSD systems The most common IGP in the Internet, RIP uses hop count as a routing metric Static route Route that is explicitly configured and entered into the routing table Static routes take precedence over routes chosen by dynamic routing protocols Focus Questions Default routes are manually defined by the system administrator as the route to take when no route to the destination is known They are also known as which of the following? a b Default subnet c Dynamic routes Default network Default routes are configured by using the _ command, while in the _ prompt a b ip default-network; Router (config)# c 233 - 239 ip default route; Router (config)# ip default-route; Router(config-if)# Engineering Journal and Workbook, Vol I, nd Ed – Chapter 26 Copyright © 2002 Cisco Systems, Inc Which of the following are used to communicate within a given autonomous system? a b Exterior Routing Protocols c Routing Information Protocols Interior Routing Protocols Routing protocols can be configured on a router while in which of the following modes? a b Router(config)# d Router# Router(config-if)# Which of the following protocols sends updated routing table information onto the network every 90 seconds? a b RIP c 234 - 239 IGRP Exterior Gateway Protocol (EGP) Engineering Journal and Workbook, Vol I, nd Ed – Chapter 26 Copyright © 2002 Cisco Systems, Inc CCNA Exam Review Questions The following questions help you review for the CCNA exam Answers also appear in Appendix A, “Answers to the CCNA Exam Review Questions,” from the Cisco Networking Academy Program: First-Year Companion Guide, Second Edition If you start the router and it cannot find Cisco IOS system image, what happens? a b The router will request that you make the Cisco IOS available c By default the router will start up in setup mode d The router will not operate The router will ask you to install any router operating system What command you use to access the setup mode? a b exec c setup d define configure If you manually set up the router, what type of configuration will it have? a b It will be minimally configured c You will only be able to use it to install Cisco IOS d It will be fully configured It will be configured in such a way that no changes can be made, except manually What kind of entries does a router initially refer to? a b Entries it has learned about from the Cisco IOS software c Entries whose IP address and mask information are known d Entries about networks or subnets that are directly connected Entries it has learned about from other routers Which of the following best describes a static route? a b Route that is explicitly configured and entered into the routing table and takes precedence over routes chosen by dynamic routing protocols c Route that adjusts automatically to network topology or traffic changes d 235 - 239 Routing table entry that is used to direct frames for which a next hop is not explicitly listed in the routing table Route that adjusts involuntarily to direct frames within a network topology Engineering Journal and Workbook, Vol I, nd Ed – Chapter 26 Copyright © 2002 Cisco Systems, Inc Which of the following best describes a dynamic routing? a b Routing that is used to direct frames for which a next hop is not explicitly listed in the routing table c Routing that adjusts automatically to network topology or traffic changes d Routing that is explicitly configured and entered into the routing table Routing that adjusts involuntarily to direct frames within a network topology What link-state algorithms require routers to do? a b Flood all its routing information to all nodes on the internetwork c Send a complete picture of the topology of the entire network to all nodes on the network d Flood routing information about the state of its own links to all nodes on the internetwork Base routing table on information provided by the every other router and send IP information to all nodes on the network An administrative distance of 15 would indicate which of the following? a b The IP address is dynamic c The routing information source is trustworthy d The IP address is static The routing information source is untrustworthy Why are routing updates not sent to a link if it is only defined by a static route? a b To conserve bandwidth c To keep routing tables small d 10 Because each node in the network already knows the route To keep routing tables organized In the following command, what does the last number stand for? router (config)# ip route 2.0.0.0 255.0.0.0 1.0.0.2 a b The number of routes to the destination c The administrative distance d 236 - 239 The number of hops The destinations reference number in the routing table Engineering Journal and Workbook, Vol I, nd Ed – Chapter 26 Copyright © 2002 Cisco Systems, Inc 11 Why would you set the administrative distance really high? a b The dynamic address may be better c The network uses OSPF d 12 The network uses Enhanced IGRP The network uses only uses default network addresses Which of following is the correct syntax when configuring a static route with an administrative distance of five? a b router (config)# ip route 2.0.0.0 255.0.0.0 1.0.0.2 c router (config)# ip route 2.0.0.0 1.0.0.2 d 237 - 239 router (config)> ip route 2.0.0.0 255.0.0.0 1.0.0.2 router (config)# ip route 2.0.0.0 255.0.0.0 1.0.0.2 Engineering Journal and Workbook, Vol I, nd Ed – Chapter 26 Copyright © 2002 Cisco Systems, Inc Chapter 27 Network Troubleshooting Introduction Troubleshooting tools that you might use for the software (IOS) include ping, trace ip route, telnet, and show arp Concept Questions Demonstrate your knowledge of these concepts by answering the following questions in the space provided • Describe typical Layer errors Layer errors can include the following (see Figure 27-2): ⇒ ⇒ Disconnected cables ⇒ Cables connected to the wrong ports ⇒ Intermittent cable connections ⇒ Cables incorrectly terminated ⇒ Wrong cables used for the tasks at hand (must use cross-connects, rollovers, and straight-through cables correctly) ⇒ Transceiver problems ⇒ DCE cable problems ⇒ DTE cable problems ⇒ • Broken cables Devices powered off Describe typical Layer errors Layer errors can include the following (see Figure 27-3): ⇒ ⇒ Improperly configured Ethernet interfaces ⇒ Incorrect clock rate settings on serial interfaces ⇒ Improper encapsulation set on serial interfaces (HDLC is default) ⇒ 238 - 239 Improperly configured serial interfaces Faulty NIC Engineering Journal and Workbook, Vol I, nd Ed – Chapter 27 Copyright â 2002 Cisco Systems, Inc ã Describe typical Layer errors Layer errors can include these (see Figure 27-4): ⇒ ⇒ Wrong routing protocol enabled ⇒ Incorrect network/IP addresses ⇒ Incorrect subnet masks ⇒ Incorrect interface addresses ⇒ Incorrect DNS-to-IP bindings (host table entries) ⇒ • Routing protocol not enabled Wrong autonomous system number for IGRP Describe some network troubleshooting strategies It’s useful to have a general method to refer to when troubleshooting computer networks This section outlines one such method used by many networking professionals The steps are as follows: Step Step Gather the facts Isolate the possible causes Step Consider the possibilities Based on the facts gathered, narrow the focus to areas relevant to the specific problem This is the step where you set the boundaries for the problem Step Create an action plan Devise a plan in which you manipulate only one variable at a time Step Implement the action plan Perform each step carefully while testing to see whether the symptom disappears Step Observe the results Determine whether you resolved the problem If so, the process is complete Step 239 - 239 Define the problem What are the symptoms and the potential causes? Repeat the process If you did not resolve the problem, move to the next most likely cause on your list Return to step 4, and repeat the process until you solve the problem Engineering Journal and Workbook, Vol I, nd Ed – Chapter 27 Copyright © 2002 Cisco Systems, Inc .. .Cisco Networking Academy Program: Engineering Journal and Workbook, Volume I, Second Edition Engineering Journal and Workbook Questions and Answers Chapter Computer... the Cisco Networking Academy Program: Engineering Journal and Workbook, Volume I, Second Edition Which of the following best defines networking? a b A connection of computers, printers, and other... of the Cisco Networking Academy Program: Engineering Journal and Workbook, Volume I Second Edition Which of the following best defines standards? a b A connection of computers, printers, and other