m07 chapter 13 quiz

Which command-line utility can you use to detect basic routing problems? (Choose all that apply.)

Ping or Pathping Tracert or Traceroute

On an Ubuntu Linux computer, in what directory and file would you find the IP address of the DNS server providing the computer with name services?

/etc/resolv.conf

The output of the ipconfig command in a Windows 10 terminal returns which information, assuming the primary network Interface is an Ethernet card? (Choose all that apply.)

The IPv4 address of the default gateway The link-local IPv6 address of the Windows host

Of the following, which is the best description of a CDN?

A CDN is a globally distributed network of proxy servers deployed in multiple data centers. The goal of a CDN is to serve content to end-users with high availability and high performance.

You want to test a number of banking and social media sites to determine if they encrypt user login credentials or leave them in plain text as a network security measure. You determine the IP addresses of the relevant sites and then run a Wireshark capture while logging in to one of them. What should you look for in the Info column of Wireshark's packet list pane to determine the right packet to examine?

Application Data

Which of the following is not a valid type of information that you may find in Wireshark's Expert Information window?

Critical; a critical problem detected, such as a network-wide service failure

When examining a Wireshark trace file related to determining why a Web site is non-responsive, where in the Expert Information window are you most likely to find messages indicating that a TCP frame is suspected of being a retransmission?

In the Note section for TCP

You want to view the Expert Information window in Wireshark to see a list of warnings, errors, and other pertinent information to a trace file you are examining. How do you open Expert Information?

In the Wireshark menu, click Analyze, and then click Expert Information.

In a Linux terminal, running the command route -n returns the IPv4 address of the computer's default gateway. What function does the -n extension perform?

It displays numeric values but not host names.

The IPv4 address 127.0.0.1 is the loopback address for which operating system? (Choose all that apply.)

Mac OS X Windows Linux

You are examining a trace file in Wireshark and notice that an ICMPv6 packet has the information "Parameter Problem (unrecognized Next Header type encountered)" in the Info column of the packet list pane. To diagnose the problem, you want to see if this packet is "talking" to other packets. How can you do this?

Right-click the ICMPv6 packet in the Wireshark packet list pane, then click Conversation Filter, and then click IPv6.

You are examining a Wireshark trace file looking for issues related to high network latency. You notice that one protocol responsible for advertisement of network services is taking 2 or 3 milliseconds to transmit compared to other packets. Of the following, which is the most likely protocol?

SSDP

You are examining a trace file in Wireshark related to a non-responsive Web site and you suspect a DNS problem. Looking in the Info column in the packet list pane, which of the following messages are more likely to indicate a DNS issue? (Choose all that apply.)

Standard query 0x97ec A www.gstatic.com Standard query 0xb40e A www.static-cisco.com

While you can sometimes tell when packet traffic, such as TCP retransmissions, is slow by looking at the time in seconds or milliseconds in the Time column of Wireshark's packet list, it isn't always self-evident. In the case of TCP retransmission traffic, what is another way to determine high latency?

The RTO, which represents the round-trip time for the TCP retransmission and can be found in the packet details pane of Wireshark under Transmission Control Protocol by expanding SEQ/ACK analysis and then expanding TCP Analysis flags

You are assessing a Windows 10 computer that cannot connect to the network at all. What is a possible cause? (Choose all that apply.)

The network port on the switch that provides the network connection for the computer is damaged. The Ethernet cable is unplugged from the computer's NIC. The computer's NIC has failed.

You are troubleshooting a DHCPv4 server and suspect there is a problem with the server's configuration. Of the following, what should you check? (Choose all that apply.)

The static IP address assignments and their associated MAC addresses The starting addresses for the managed pools under Dynamic Address Pool settings The subnet masks for the Static Pool settings

The output of the ifconfig command in a Linux terminal returns which information? (Choose all that apply.)

The subnet mask used by the Linux host The MAC address of the NIC The IPv4 address of the Linux host

You are assessing a Windows 10 computer that is displaying a message "limited or no connectivity." You open a command prompt window, type ipconfig /all, and then press Enter. You see the IPv4 address of the computer's primary network interface is 169.254.69.8. What is the problem?

This is an APIPA, which the Windows computer assigned to its network interface because a DHCP server isn't available to dynamically provide addressing services.

Normally, before testing a network for high latency or slow performance problems, what should you establish?

You should use a protocol analyzer like Wireshark to determine a baseline of normal network activity at different times, such as low and peak network usage.

You are assessing a network connection problem involving a Windows 10 computer on an IPv6 network. The issue was caused by the temporary unavailability of the local DHCPv6 server. The server has since come back up. You want to refresh the PC's IPv6 address by having the previous one be removed and requesting a new one. At the command prompt, what commands do you type?

ipconfig /release6 and then ipconfig /renew6