network fundamentals ch 13

Destination Unreachable codes for ICMPv4 are as follows

0 - Net unreachable 1 - Host unreachable 2 - Protocol unreachable 3 - Port unreachable

traceroute tool.

Time Exceeded messages are used by the

ping command.

To test connectivity to another host on a network, an echo request is sent to the host address using the

Type of connectivity tests performed with ping include the following:

Pinging the local loopback Pinging the default gateway Pinging the remote host

What characterizes a traceroute utility?

it identifies the router in the path from a source host to a destination host

A user calls to report that a PC cannot access the internet. The network technician asks the user to issue the command ping 127.0.0.1 in a command prompt window. The user reports that the result is four positive replies. What conclusion can be drawn based on this connectivity test?

the TCP/IP implementation

A technician is troubleshooting a network where it is suspected that a defective node in the network path is causing packets to be dropped. The technician only has the IP address of the end point device and does not have any details of the intermediate devices. What command can the technician use to identify the faulty node?

tracert

Which two types of ICMP messages are common to both ICMPv4 and ICMPv6? (Choose two.)

destination or service unreachable time exceeded

Ping

has a timeout value for the reply. If a reply is not received within the timeout, provides a message indicating that a response was not received. This may indicate that there is a problem, but could also indicate that security features blocking ping messages have been enabled on the network.

What message is sent by a host to check the uniqueness of an IPv6 address before using that address?

neighbor solicitation

Which command can be used to test connectivity between two devices using echo request and echo reply messages?

ping

Which utility uses the Internet Control Messaging Protocol (ICMP)?

ping

RFC 4861

recommends that DAD is performed on unicast addresses.

Which two things can be determined by using the ping command? (Choose two.)

the average time it takes a packet to reach the destination and for the response to return to the source the destination device is reachable through the network

A user who is unable to connect to the file server contacts the help desk. The helpdesk technician asks the user to ping the IP address of the default gateway that is configured on the workstation. What is the purpose for this ping command?

to test that the host has the capability to reach hosts on other networks

Ping can also be used

to test the ability of a local host to communicate across an internetwork. The local host can ping an operational IPv4 host of a remote network, as shown in the figure.

NA message

The device that has the targeted IPv6 address will respond with an __containing its Ethernet MAC address.

RA messages

are sent by IPv6-enabled routers every 200 seconds to provide addressing information to IPv6-enabled hosts. can include addressing information for the host such as the prefix, prefix length, DNS address, and domain name. A host using Stateless Address Autoconfiguration (SLAAC) will set its default gateway to the link-local address of the router that sent the RA.

What field content is used by ICMPv6 to determine that a packet has expired?

hop limit field

Ping can be used to test

the internal configuration of IPv4 or IPv6 on the local host. To perform this test, ping the local loopback address of 127.0.0.1 for IPv4 (::1 for IPv6).

ICMPv6 ND also includes the redirect message

which has a similar function to the redirect message used in ICMPv4.

NS message

with its own IPv6 address as the targeted IPv6 address, will notify the sending device that the address is in use. If a corresponding ___ is not returned within a certain amount of time, the unicast address is unique and acceptable for use.

Destination Unreachable codes for ICMPv6 are as follows:

0 - No route to destination 1 - Communication with the destination is administratively prohibited (e.g., firewall) 2 - Beyond scope of the source address 3 - Address unreachable 4 - Port unreachable

What is a function of the tracert command that differs from the ping command when they are used on a workstation?

the Tracert command shows the information of routers in the path

Which ICMP message is used by the traceroute utility during the process of finding the path between two end hosts?

time exceeded

successful ping

to the default gateway indicates that the host and the router interface serving as the default gateway are both operational on the local network.

Which type of ICMPv6 message would a host send to acquire an IPv6 configuration when booting up?

router solicitation (RS) message

Messaging between IPv6 devices, including duplicate address detection and address resolution are as follows:

Neighbor Solicitation (NS) message Neighbor Advertisement (NA) message

Which protocol is used by IPv4 and IPv6 to provide error messaging?

ICMP

A network administrator is testing network connectivity by issuing the ping command on a router. Which symbol will be displayed to indicate that a time expired during the wait for an ICMP echo reply message?

.

RS message.

An IPv6-enabled router will also send out an RA message in response to an

ICMP messages common to both ICMPv4 and ICMPv6 and discussed in this module include:

Host reachability Destination or Service Unreachable Time exceeded

Which protocol provides feedback from the destination host to the source host about errors in packet delivery?

ICMP

Messaging between an IPv6 router and an IPv6 device, including dynamic address allocation are as follows:

Router Solicitation (RS) message Router Advertisement (RA) message

ICMPv6 includes four new protocols as part of the Neighbor Discovery Protocol (ND or NDP).

Router Solicitation (RS) message Router Advertisement (RA) message Neighbor Solicitation (NS) message Neighbor Advertisement (NA) message

ICMP

is available for both IPv4 and IPv6.

ICMPv4

is the messaging protocol for IPv4 provides these same services for IPv6 but includes additional functionality.

Round Trip Time (RTT)

is the time a packet takes to reach the remote host and for the response from the host to return. An asterisk (*) is used to indicate a lost or unreplied packet.

ICMPv4 Time Exceeded message

is used by a router to indicate that a packet cannot be forwarded because the Time to Live (TTL) field of the packet was decremented to 0. If a router receives a packet and decrements the TTL field in the IPv4 packet to zero, it discards the packet and sends a Time Exceeded message to the source host.

A network administrator can successfully ping the server at www.cisco.com, but cannot ping the company web server located at an ISP in another city. Which tool or command would help identify the specific router where the packet was lost or delayed?

traceroute

Traceroute (tracert) is a

utility that generates a list of hops that were successfully reached along the path. This list can provide important verification and troubleshooting information. If the data reaches the destination, then the trace lists the interface of every router in the path between the hosts.