CCNA1 (Chapter11)

Which statement is true about Cisco IOS ping indicators?​

'U' may indicate that a router along the path did not contain a route to the destination address and that the ping was unsuccessful. Refer to curriculum topic: 11.3.1 The most common indicators of a ping issued from the Cisco IOS are "!", ".", and "U". The "!" indicates that the ping completed successfully, verifying connectivity at Layer 3. The "." may indicate that a connectivity problem, routing problem, or device security issue exists along the path and that an ICMP destination unreachable message was not provided. The "U" indicates that a router along the path may not have had a route to the destination address, and that it responded with an ICMP unreachable message.

On which two interfaces or ports can security be improved by configuring executive timeouts? (Choose two.)

1. console ports 2. vty ports Refer to curriculum topic: 11.2.4 Executive timeouts allow the Cisco device to automatically disconnect users after they have been idle for the specified time. Console, vty, and aux ports can be configured with executive timeouts.

Match the type of threat with the cause. (Not all options are used.)

1. hardware threats: physical damage to servers, routers, switches, cabling plant, and workstations 2. environmental threats: temperature extremes (too hot or too cold) or humidity extremes (too wet or too dry) 3. electrical threats: voltage spikes, insufficient supply voltage (brownouts), unconditioned power (noise), and total power loss 4. maintenance threads: poor handling of key electrical components (electrostatic discharge), lack of critical spare parts, poor cabling, and poor labeling Refer to curriculum topic: 11.2.1

Which process failed if a computer cannot access the Internet and received an IP address of 169.254.142.5?

DHCP Refer to curriculum topic: 11.4.3 When a Windows computer cannot communicate with an IPv4 DHCP server, the computer automatically assigns itself an IP address in the169.254.0.0/16 range. Linux and Apple computers do not automatically assign an IP address.

What is considered the most effective way to mitigate a worm attack?

Download security updates from the operating system vendor and patch all vulnerable systems. Refer to curriculum topic: 11.2.3 Because worms take advantage of vulnerabilities in the system itself, the most effective way to mitigate worm attacks is to download security updates from the operating system vendor and patch all vulnerable systems.

How should traffic flow be captured in order to best understand traffic patterns in a network?

During Peak utilization times Refer to curriculum topic: 11.1.3 Capturing traffic during low utilization time will not give a good representation of the different traffic types. Because some traffic could be local to a particular segment, the capture must be done on different network segments.

A small company has only one router as the exit point to its ISP. Which solution could be adopted to maintain connectivity if the router itself, or its connection to the ISP, fails?

Have a second router that is connected to another ISP. Refer to curriculum topic: 11.1.1 Small networks generally have only one link to an ISP to establish a connection to the Internet. Problems can occur in the network, which can cause the disruption of this service. In order to keep connectivity, redundancy has to be provided. If the problem is in the router interface that is connected to the ISP, another interface can be activated on the router, so if one interface fails, traffic may be redirected toward the other interface. However, if the router itself fails, a second router that is connected to another ISP can be used as a backup.

Which protocol is used by the traceroute command to send and receive echo-requests and echo-replies?

ICMP Refer to curriculum topic: 11.3.2 Traceroute uses the ICMP (Internet Control Message Protocol) to send and receive echo-request and echo-reply messages.

Which command will block login attempts on RouterA for a period of 30 seconds if there are 2 failed login attempts within 10 seconds?

RouterA(config)# login block-for 30 attempts 2 within 10 Refer to curriculum topic: 11.2.4 The correct syntax is RouterA(config)# login block-for (number of seconds) attempts (number of attempts) within (number of seconds).

Refer to the exhibit. The exhibited configuration is entered by a network administrator into a new router. Sometime later a network technician proceeds to log in to the router via a console connection. The technician enters techadmin as the user name and tries a password of 63t0ut0fh3r3!. What will be the result of this action?

The router will display the DT_ATC_RS3> prompt. Refer to curriculum topic: 11.2.4 Whenever an administrator connects to the console port, the configuration applied under the line con 0 interface determines how the user is authenticated. The console port configuration has the login command with local as the keyword. That means the username and password are required before the administrator is even allowed to see the enable mode prompt. Because the correct username and password was typed, the administrator will be presented with the enable mode prompt.

What is one of the most effective security tools available for protecting users from external threats?

firewall Refer to curriculum topic: 11.2.3 A firewall is one of the most effective security tools for protecting internal network users from external threats. A firewall resides between two or more networks, controls the traffic between them, and helps prevent unauthorized access. A host intrusion prevention system can help prevent outside intruders and should be used on all systems.

A particular website does not appear to be responding on a Windows 7 computer. What command could the technician use to show any cached DNS entries for this web page?

ipconfig /displaydns Refer to curriculum topic: 11.3.4

Which element of scaling a network involves identifying the physical and logical topologies?

network documentation Refer to curriculum topic: 11.1.3 To scale a network, several elements are required: - Network documentation - physical and logical topology - Device Inventory - list of devices that use or make up the network - Budget - Itemized IT budget, including fiscal year equipment purchasing budget - Traffic analysis - protocols, applications, and services and their respective traffic requirements should be documented

Fill in the blank. Network services use ________ to define a set of rules that govern how devices communicate and the data formats used in a network.

protocols Refer to curriculum topic: 11.1.2 Each application or network service uses protocols, which define the standards and data formats to be used. Without protocols, the data network would not have a common way to format and direct data.

An administrator wants to back up a router configuration file to a USB drive that is connected to the router. Which command should the administrator use to verify that the USB drive is being recognized by the router?

show file systems Refer to curriculum topic: 11.2.5 The show file systems command displays all of the available file systems on the device. If usbflash0: appears then the router recognizes the USB drive as a valid storage device. The pwd command shows the current directory being navigated, and the cd command is used to change the current directory. The dir flash0: command will show the contents of flash memory, not the USB drive.

A network technician is investigating network connectivity from a PC to a remote host with the address 10.1.1.5. Which command, when issued on a Windows PC, will display the path to the remote host?

tracert 10.1.1.5 Refer to curriculum topic: 11.3.2 The tracert command is used to initiate a trace from the command prompt on a Windows PC. The traceroute command is used to initiate a trace from a Cisco router or switch. Some other PC operating systems, such as Linux and Mac OS also use the traceroute command. The ping command does not display the network path to the remote host.

What type of traffic would most likely have the highest priority through the network?

voice Refer to curriculum topic: 11.1.1 Not all traffic should receive the same treatment or priority through a network. Some types of traffic, such as voice and video, require the highest priority because they are very sensitive to network latency and delay. Other types of traffic, such as FTP which is not sensitive to latency and delay, should be given the lowest levels of priority so that the higher priority traffic can get through.